Anthropogeny

The video begins with a narration that introduces the concept of humanity as a "paradoxical ape," highlighting our unique characteristics such as bipedalism, lack of body hair, large brains, and mastery over fire, tools, and language. Despite these advancements, the narrator emphasizes our ongoing quest to understand ourselves, our existence, and our future, acknowledging the inevitability of death while maintaining an optimistic outlook. This exploration of human origins is facilitated by CARTA (Center for Academic Research and Training in Anthropogeny), which brings together experts from various disciplines to share insights into our past and future.

The 35th CARTA symposium focuses on the origins of modern humans, addressing fundamental questions about our identity and existence. The symposium aims to utilize scientific methods to explore two primary questions: where did we come from, and how did we get here? The speakers will draw from a wide array of data and analytical methods, emphasizing the importance of interdisciplinary collaboration among fields such as humanities, biological sciences, engineering, computing, physical and chemical sciences, biomedical sciences, and social sciences. This collaborative approach is crucial for formulating better questions and finding more effective answers regarding human origins.

CARTA is described as an organized research unit at the University of California, San Diego (UCSD), in partnership with the Salk Institute for Biological Studies. The center's mission is to explore and explain the origins of the human phenomenon, co-directed by notable figures in the field. The symposium is supported by generous sponsors, including the G. Harold and Leila Y. Mathers Foundation, and the organizers express gratitude for the support received, inviting further contributions to various aspects of CARTA's work, such as symposium series, graduate fellowships, and field courses.

As the symposium progresses, Mark Collard, one of the co-chairs, addresses the audience, explaining that he and his co-chair, Kristen Hawkes, were not the original speakers due to last-minute withdrawals from the scheduled chairs. He acknowledges the stellar roster of speakers prepared by the original chairs and sets the stage for discussions centered on the origin, evolution, and dispersal of Homo sapiens. The last time this topic was covered by CARTA was six years ago, and Collard notes the exciting discoveries made since then, which will enrich the discussions.

The symposium will cover four main lines of evidence regarding human origins: skeletal anatomy, archaeology, genetics of living humans, and DNA from ancient hominid remains. Additionally, the talks will delve into the intriguing species Homo naledi and its relevance to the narrative of human evolution. Collard emphasizes the interdisciplinary nature of human origins research, noting that it involves contributions from over a dozen distinct disciplines. Despite the complexity, there have been few institutional mechanisms to foster collaboration among these diverse fields. CARTA stands out as a significant and enduring attempt to create such interdisciplinary organizations focused on human origins.

Collard encourages attendees to support CARTA by visiting its website and making donations, highlighting that every contribution helps sustain the organization's work. He also suggests writing letters of appreciation to the leaders of UCSD and the Salk Institute, reinforcing the importance of community support for the continuation of CARTA's initiatives. The call for support underscores the value of CARTA's research in benefiting not only the academic community but also the broader public, emphasizing the need for recognition of its contributions to understanding human origins.

The transcript does not explicitly mention any specific hominin species or human-like groups such as Australopithecus, Homo erectus, or Neanderthals. Furthermore, there are no details provided regarding specific time periods or geographical locations associated with any hominin species. The focus of the discussion at the CARTA symposium appears to be more on the broad themes of human origins and evolution rather than detailing individual species.

• • [01:48] "One thing we do as humans is ask questions and among the oldest questions that we continue asking are who are we?"
  • [01:29] "CARTA brings together experts from diverse disciplines to exchange insights on who we are and how we got here."

The transcript provides several central claims and assertions regarding the process of human evolution. The symposium emphasizes the importance of understanding human origins through interdisciplinary collaboration, suggesting that insights from a variety of fields are essential to unraveling the complexities of human evolution. Key points made include:

• Interdisciplinary Approach: The necessity of integrating knowledge from humanities, biological sciences, social sciences, and other fields to develop a comprehensive understanding of human origins.
• Human Phenomenon: The mission of CARTA is framed as exploring and explaining the origins of the human phenomenon, which implies a deep investigation into both our biological and cultural evolution.
• Scientific Inquiry: The speaker asserts that two of the oldest questions, specifically where did we come from? and how did we get here?, are now approachable through scientific means, indicating a shift towards empirical research in anthropology.
• Evolutionary Context: The symposium addresses the evolutionary context of Homo sapiens, underscoring that the understanding of human origins is not static but evolves with new discoveries.

Overall, the transcript suggests that pivotal developments in human evolution involve both anatomical and cognitive advancements, although specific examples are not detailed in this segment.

• • [02:15] "A large variety of data and ways to analyze new data, combine data, so these two questions, where did we come from? And how did we get here? Are what anthropogeny is about the study of human origins."
  • [06:57] "Human origins research is inherently and intensely interdisciplinary."

In the transcript, the speaker refers to multiple types of data and evidence that are crucial for supporting claims about human evolution. Although specific examples of fossils or genetic data are not detailed, a general framework for the types of evidence utilized in anthropogeny is outlined. The mentioned types of evidence include:

• Skeletal Anatomy: The analysis of skeletal remains is vital for understanding the physical evolution of humans, helping to identify adaptations and morphological changes over time.
• Archaeological Evidence: Findings from archaeological sites provide context for the behavioral aspects of early human life, including tool use and cultural practices.
• Genetic Studies: Research into the genetics of living humans allows scientists to trace lineage and evolutionary relationships, shedding light on how modern humans are connected to their ancestors.
• Ancient DNA: The transcript mentions DNA extracted from ancient hominid remains, which is crucial for understanding both genetic variation and the interrelation of different hominin species.

Collectively, these evidence types form a multidisciplinary approach to understanding the evolutionary lineage of Homo sapiens and related species. The symposium's structure, which includes discussions on recent discoveries, indicates a commitment to integrating new findings into the broader narrative of human evolution.

• • [06:22] "The talks cover four main lines of evidence pertaining to the origins of living humans, skeletal anatomy, archaeology, the genetics of living humans and DNA extracted from ancient hominid remains."
  • [06:36] "In addition, we're gonna hear about the latest research on the rather puzzling hominid species, homo naledi and how it fits into the picture of later human evolution."

The transcript does not explicitly discuss the reliability, certainty, or quality of the data being examined in the context of anthropogeny. However, it implies that the field is characterized by a dynamic and evolving understanding of human origins, as indicated by the mention of recent discoveries since the last CARTA symposium, which was held six years ago. This suggests an acknowledgment of the incompleteness of the fossil record and the ongoing nature of research in this area.

The speaker, Mark Collard, notes that the focus of the symposium is on the origin, evolution, and dispersal of Homo sapiens, highlighting the complexity of these topics. The mention of four main lines of evidence suggests a multidisciplinary approach, indicating that the scientific community is aware of the varied sources and types of data that contribute to our understanding of human evolution. These lines include:

• Skeletal anatomy
• Archeology
• Genetics of living humans
• DNA extracted from ancient hominid remains

While the transcript does not directly address gaps in the fossil record or the fragility of evidence, it is reasonable to infer that discussions occurring during the symposium might touch on such issues, given the nature of anthropogeny as an interdisciplinary field that thrives on the integration of various scientific perspectives.

• [06:05] "The last time CARTA covered this topic was six years ago and there have been many exciting discoveries in the intervening period."
• [06:18] "The talks cover four main lines of evidence pertaining to the origins of living humans, skeletal anatomy, archeology, the genetics of living humans and DNA extracted from ancient hominid remains."
• [07:57] "Human origins research is inherently and intensely interdisciplinary."

The transcript indicates that there are ongoing scientific debates regarding the origins and evolution of humans, specifically within the framework of anthropogeny. Mark Collard mentions that today’s symposium will cover a variety of topics, including the origin, evolution, and dispersal of Homo sapiens, revealing the complexity and multifaceted nature of these discussions. However, the transcript does not specify particular debates, competing hypotheses, or disagreements within the field.

It does highlight the importance of interdisciplinary collaboration, suggesting that researchers from various fields are engaged in efforts to understand human evolution. This interdisciplinary approach is necessary due to the complexity of human origins, which likely involves debates over migration routes, ancestor-descendant relationships, and possibly behavioral traits as well.

For example, Collard notes that there have been many exciting discoveries since the last symposium, which may imply that various hypotheses have been proposed or revised based on new evidence. The transcript emphasizes the need for collaboration among disciplines, which indicates that multiple perspectives are being considered and discussed, although specific controversies are not detailed in the text.

• [02:22] "Where did we come from? And how did we get here? Are what anthropogeny is about the study of human origins."
• [06:01] "The focus of the symposium is the origin, evolution and dispersal of our species, homo sapiens."
• [07:00] "As today's talks will actually demonstrate, researchers from more than a dozen different, distinct, disciplines are engaged in the effort to try and understand human evolution."

[00:00] (wind whipping) (mouse clicking)
[00:05] (chiming music)
[00:09] - [Narrator] We are the paradoxical ape,
[00:12] bipedal, naked, large brained,
[00:17] long the master of fire, tools and language
[00:21] but still trying to understand ourselves.
[00:25] Aware that death is inevitable,
[00:29] yet filled with optimism.
[00:32] We grow up slowly, we hand down knowledge,
[00:37] we empathize and deceive.
[00:41] We shape the future from our shared understanding
[00:43] of the past.
[00:46] CARTA brings together experts from diverse disciplines
[00:50] to exchange insights on who we are and how we got here.
[00:56] An exploration made possible
[00:57] by the generosity of humans like you.
[01:00] (chiming music)
[01:15] (upbeat music)
[01:39] - Good afternoon and welcome
[01:40] to this 35th CARTA symposium
[01:43] which explores the origin of today's humans.
[01:48] One thing we do as humans is ask questions
[01:50] and among the oldest questions
[01:52] that we continue asking are who are we?
[01:56] What are we doing here?
[01:58] Where did we come from?
[02:00] How did we get here?
[02:02] Where are we going?
[02:04] Many of us have wonderful stories
[02:06] as attempts to answer these questions.
[02:08] We at CARTA believe
[02:09] that two of these questions are now amenable
[02:11] to attempts at answering them using scientific means.
[02:15] A large variety of data and ways to analyze new data,
[02:19] combine data, so these two questions,
[02:22] where did we come from?
[02:23] And how did we get here?
[02:25] Are what anthropogeny is about the study of human origins.
[02:29] We believe that the only way to get there is
[02:32] to recruit different minds from the humanities,
[02:35] the biological sciences, engineering, computing sciences,
[02:38] physical and chemical sciences, biomedical sciences
[02:41] and the social sciences
[02:43] and in a dialogue exchange perspective
[02:46] and learn from each other and come up with better questions
[02:48] and better ways to attempt to answer these.
[02:52] CARTA is an organized research unit
[02:54] at UCSD and exists between UCSD
[02:57] and the Salk Institute for Biological Studies.
[03:00] CARTA stands for
[03:00] Center for Academic Research and Training in Anthropogeny.
[03:05] It's a transdisciplinary collaboration
[03:08] and our goal, our mission statement, is to explore
[03:11] and explain the origins of the human phenomenon.
[03:15] It's co-directed by Ajit Varki, Fred Gage
[03:19] and Margaret Schoeninger and myself.
[03:24] We are very, very grateful for our major sponsors,
[03:27] the G. Harold and Leila Y. Mathers Foundation
[03:31] and it's Executive Director, Howard Chester.
[03:34] We also have major sponsors
[03:37] that have given very generous support to this project,
[03:43] a long list of people who support us
[03:46] and if you should be considering
[03:47] supporting various aspects of CARTA,
[03:50] there are different facets that we invite you to support,
[03:53] from the Symposium Series through the Graduate Fellowships
[03:57] to the Field Course to the James H. Handelman,
[04:00] Jim Handelman Endowment for the Exploration of Anthropogeny
[04:04] and I'd like to give a special thanks to Liz Lancaster
[04:06] and Eli Shefter who are sponsoring the closed captioning
[04:10] of today's event.
[04:14] I'd also like to thank the CARTA staff,
[04:16] Lindsay Hunter, Kate Kaya, Linda Nelson and Jesse Robie,
[04:20] UCSD-TV that is recording today's events,
[04:22] Rich Wargo, Steve Anderson, Marci Bretts and John Menier,
[04:27] the Salk Media Services, Kent Schnoeker and Mike Jeffs,
[04:31] George Svoboda who played for us today
[04:34] and our CARTA volunteer, Busi Mafanya.
[04:39] With this, I'd like to hand the floor to Mark Collard,
[04:42] our first co-chair.
[04:44] - Good afternoon and thanks for coming.
[04:48] Just want to start off by explaining
[04:50] that I wasn't supposed to be standing here
[04:53] in front of you today.
[04:55] Nor was the other co-chair for today,
[04:57] Professor Kristen Hawkes.
[05:00] The original chairs
[05:01] for the meeting were Professor Richard Klein
[05:03] of Stanford University
[05:05] and Professor Sarah Tishkoff
[05:07] of the University of Pennsylvania.
[05:09] However, Richard had to withdraw a few weeks ago
[05:13] and I was asked whether I could cover for him
[05:15] and then last weekend Sarah also had to withdraw
[05:20] and Kristen was asked whether she could step
[05:23] into the breach, which she kindly did.
[05:26] So, arrangements have been a bit fluid.
[05:31] Anyhow, I suspect that Richard
[05:34] and Sarah are watching the live feed
[05:37] of the talks this afternoon,
[05:39] so I'd like to ask you to please join me in thanking them
[05:41] for putting together what is a stellar roster
[05:43] of speakers for us.
[05:45] (audience claps)
[05:53] Thank you, if you haven't wandered
[05:54] into the auditorium by accident,
[05:57] you'll know that the focus
[05:58] of the symposium is the origin, evolution
[06:01] and dispersal of our species, homo sapiens.
[06:05] The last time CARTA covered this topic was six years ago
[06:09] and there have been many exciting discoveries
[06:12] in the intervening period,
[06:15] so we're in for a fascinating afternoon.
[06:18] The talks cover four main lines of evidence pertaining
[06:22] to the origins of living humans, skeletal anatomy,
[06:26] archeology, the genetics of living humans
[06:29] and DNA extracted from ancient hominid remains.
[06:34] In addition, we're gonna hear about the latest research
[06:36] on the rather puzzling hominid species, homo naledi
[06:40] and how it fits into the picture of later human evolution.
[06:44] Okay, before I hand over to the first speaker,
[06:47] I just want to say a few words
[06:48] about CARTA and interdisciplinarity.
[06:52] Okay, so, human origins research is inherently
[06:57] and intensely interdisciplinary.
[07:00] As today's talks will actually demonstrate.
[07:03] So, researchers from more
[07:05] than a dozen different, distinct, disciplines are engaged
[07:09] in the effort to try and understand human evolution.
[07:14] However, there have been surprisingly few attempts
[07:18] to create institutional mechanisms
[07:21] that foster knowledge exchange and collaboration
[07:25] among researchers (coughs) from those different disciplines.
[07:30] To the best of my knowledge, CARTA is the broadest,
[07:33] in terms of the disciplines it covers
[07:36] and also the longest lasting of the very few attempts
[07:40] that have been made
[07:41] to set up these sort of interdisciplinary organizations
[07:46] with a focus on human origins.
[07:48] As such, it's really rather precious, okay?
[07:54] So, I'd like to ask you
[07:56] to consider visiting the CARTA website
[08:00] and making a donation the URL for the website is given
[08:03] in the program.
[08:05] Every little helps, of course.
[08:07] If you're not in a position to do that,
[08:11] a good alternative would be to write the leaders
[08:14] of the University of California San Diego
[08:16] and the Salk Institute
[08:18] and express you gratitude for
[08:20] and appreciation of the work that CARTA does.
[08:26] As you can probably imagine,
[08:28] it's easier for faculty members to go to leaders,
[08:32] the senior administration of universities
[08:34] and research institutions
[08:36] and ask for support for initiatives, if they can see,
[08:39] if they've got a clear indication that it benefits people
[08:43] beyond their own university,
[08:45] if it benefits the broader community.
[08:47] So, emails and letters of support would be very helpful too.
[08:51] So, thank you in advance for your assistance
[08:53] with keeping CARTA's work going.
[08:55] (chiming music)

Introduction to the Paradoxical Ape

The video begins with a narration that introduces humans as the "paradoxical ape," characterized by bipedalism, lack of body hair, and large brains. Despite our advanced capabilities in fire, tool-making, and language, we still grapple with self-understanding. The narrative emphasizes our awareness of mortality and the optimism that accompanies our slow growth and knowledge transmission. The Center for Academic Research and Training in Anthropogeny (CARTA) aims to bring together experts from various fields to deepen our understanding of human origins and evolution, highlighting the importance of public support for such endeavors.

William's Perspective on Human Origins

William, a speaker at the event, expresses skepticism about our understanding of the origins of the genus Homo, suggesting that we know very little. He acknowledges the fossil record's richness but points out that it primarily covers the last two million years, leaving a significant gap in our understanding of earlier ancestors. He likens the challenge of reconstructing human evolutionary history to piecing together a car wreck from minimal evidence, emphasizing the need for more discoveries from older strata.

Historical Context of Homo Evolution Studies

William discusses the modern history of Homo evolution studies, tracing back to Louis Leakey's recognition of Homo habilis in 1964. This species was identified based on fossils from Olduvai Gorge, which exhibited human-like dexterity, increased brain size, and reduced tooth size. These features led researchers to place Homo habilis at the base of the Homo lineage. Philip Tobias, a co-author of the species description, famously claimed that Homo habilis filled a significant gap in the story of human evolution. The narrative of human evolution was initially viewed as a linear progression towards modern humans, characterized by specific traits that emerged gradually over time.

Challenges in Understanding Early Homo

However, the fossil record before two million years ago is sparse, leading to debates about whether human traits developed piecemeal or as a cohesive package. Since the 1980s, research has revealed a more complex picture of the genus Homo, with multiple contemporaneous species existing around two million years ago, including Homo rudolfensis, Homo habilis, and Homo erectus. This diversity suggests that there may not be a single adaptive package that explains the evolution of all these forms, prompting questions about their origins and the environmental conditions that influenced their development.

Environmental Factors and the Origin of Homo

William highlights the significance of global climatic changes around the time the Homo lineage is believed to have emerged. These changes included the expansion of ice sheets and a drying out of the African interior, which may have influenced the evolution of early hominids and the development of stone tools. However, the lack of fossil evidence from this critical period complicates our understanding of these evolutionary processes. The Oldowan tools, dating to around 2.6 million years ago, may or may not be directly associated with the genus Homo, raising further questions about the capabilities of earlier species.

Research Focus in Ethiopia

William discusses ongoing research in Ethiopia, particularly in the Ledi-Geraru area, where his team aims to fill the gaps in the fossil record between Australopithecus and the genus Homo. The sediments in this region span a crucial time frame from 2.8 to 2.6 million years ago, providing an opportunity to explore the evolutionary developments leading to the emergence of Homo. The research team has been studying various fault blocks, which offer unique slices of time, allowing for a more detailed understanding of the environmental contexts in which early hominids lived.

Discovery of a Significant Jaw Fossil

In 2013, a graduate student discovered a jaw fossil in the Gurumaha block, dated to approximately 2.8 million years ago. This find is significant as it provides a data point in an otherwise sparse record of early Homo. William argues against the myth that only complete skeletons can yield meaningful insights, citing numerous species identified from fragmentary remains. The jaw exhibits characteristics that align more closely with later Homo species than with Australopithecus, suggesting that it may represent an early member of the Homo lineage.

Comparative Analysis of Jaw Fossils

William compares the newly discovered jaw to those of Australopithecus and Homo erectus, noting distinct differences in morphology. The Ledi-Geraru jaw displays features that are more consistent with later Homo species, indicating a potential evolutionary trajectory. This analysis raises questions about the adaptive packages present in early Homo and the environmental conditions that may have influenced their evolution.

Implications for Understanding Human Evolution

Finally, William discusses the implications of these findings for our understanding of human evolution. The evidence suggests that the environment in which early Homo lived was likely more open and grassland-like compared to the habitats of earlier Australopithecus species. This shift in environment may have played a role in the evolutionary adaptations of the genus Homo. Additionally, new findings from Kenya suggest that stone tool use may predate the genus Homo, potentially pushing back the timeline for the emergence of technological behaviors.

Conclusion

In conclusion, the research conducted in the Ledi-Geraru area and the discovery of the jaw fossil contribute valuable insights into the origins of the genus Homo. While many questions remain unanswered, the findings highlight the complexity of human evolution and the need for continued exploration and research in this field. The evolving narrative of our origins underscores the dynamic interplay between environmental factors and evolutionary adaptations, paving the way for a deeper understanding of what it means to be human.

The transcript mentions several significant hominin species and human-like groups, each associated with specific time periods and geographical locations. The prominent species discussed include:

• Homo habilis: Recognized in 1964, this species is dated to approximately 1.7 to 1.75 million years ago and is associated with the Olduvai Gorge in Tanzania. It is characterized by a notable increase in brain size and a dexterous ability in the hands, which are considered emblematic of early human-like traits.
• Homo erectus: Mentioned in relation to a jawbone found at the Dmanisi site, dated to around 1.8 million years ago. This species illustrates the evolutionary trajectory leading towards modern humans.
• Australopithecus afarensis: This species, famously represented by the fossil named 'Lucy', is dated to about 3 million years ago and is primarily found in East Africa, specifically the Hadar region.
• Australopithecus africanus: Closely related to Australopithecus afarensis, this species is mentioned in connection with the Ledi-Geraru findings and is also associated with South Africa.
• Robust Australopithecines: While not a specific species, these groups are suggested to have evolved around the same time as the genus Homo, potentially impacted by environmental changes.

Additionally, the transcript discusses the lack of fossils for the genus Homo prior to 2 million years ago, indicating the challenges faced in understanding the early evolutionary timeline of our lineage.

• [04:10] "The modern history of the study of the evolution of the genus Homo really begins with Louis Leakey and colleagues and the recognition of the species, Homo habilis in 1964."
• [10:24] "All of these fossils have been promoted by one person or another as identifying the genus Homo older than 2.0 million years ago and all of them have been doubted."
• [22:57] "The modal environmental signal at 2.8 in this area is one essentially of a grassland environment."

The transcript presents several central claims regarding the process of human evolution, emphasizing the complexity and challenges in understanding our ancestral lineage. Key assertions include:

• Knowledge Gaps: The speaker expresses a nihilistic view regarding the origins of the genus Homo, suggesting that despite the fossil record, much remains unknown about the evolutionary history of this group. This is likened to reconstructing a history using minimal, fragmented evidence.
• Adaptive Diversity: The existence of multiple species such as Homo habilis, Homo erectus, and Homo rudolfensis suggests that there is not a singular adaptive package that defines human evolution. Instead, these species may have evolved under various adaptive pressures.
• Environmental Influences: The transcript discusses how significant climatic changes may have played a role in the evolution of early hominins. The drying out of Africa is linked to the emergence of certain adaptations, including tool use and dietary changes.
• Jaw Morphology: A newly discovered jaw from Ledi-Geraru, dated to 2.8 million years ago, shows anatomical features that align more closely with Homo than with earlier Australopithecines, indicating possible early traits of the genus.

These claims collectively highlight the intricate interplay of anatomical, behavioral, and environmental factors that have shaped human evolution, suggesting that our understanding is still evolving as new discoveries are made.

• [02:25] "My view is we actually know nothing about the origin of Homo, just saying."
• [07:44] "The idea that there is not one adaptive package that can describe them all, but there are perhaps multiple ones."
• [21:19] "This is a jaw that exhibits characteristics that forecast anatomy that is common, the most common anatomical patterns in jaws of the genus Homo younger than 2 million."

In the transcript, the speaker refers to several specific types of data and evidence that support their claims about human evolution:

• Fossil Evidence: The discussion highlights various fossils attributed to different hominin species, including the jawbone found in the Ledi-Geraru area, which is dated to 2.8 million years ago. This fossil is significant as it shows morphological traits closely associated with the genus Homo.
• Comparative Anatomy: The speaker compares the morphology of the Ledi-Geraru jaw to that of Australopithecus afarensis and Homo erectus, noting distinct differences that suggest an evolutionary transition within the genus Homo.
• Archaeological Finds: Mentions of stone tools, specifically Oldowan tools dated to around 2.6 million years, provide context for technological advancements and their potential correlation with early hominin behavior.
• Geological Context: The speaker describes the sedimentary environments of the Ledi-Geraru area, indicating how the geological conditions can inform our understanding of the habitats in which these early hominins lived.
• Paleoecological Data: Evidence from animal fossils found alongside the Ledi-Geraru jaw suggests that the environment was predominantly grassland, providing insights into the ecological conditions that may have influenced hominin evolution.

This multifaceted approach, integrating fossil records, comparative studies, and ecological data, illustrates the complexity of reconstructing the evolutionary history of humans.

• [08:32] "I think it speaks fairly clearly to the idea that these three at 2 million did in fact share a single unified ancestry predating that time period."
• [10:31] "We do have of course Oldowan tools at around 2.6 million."
• [22:11] "This jaw is found in a context of animal species that lived in essentially grassland environments."

The transcript reveals significant uncertainty regarding the fossil record and the evolutionary history of the genus Homo. The speaker expresses a strong skepticism about the current understanding of the origins of Homo, stating, "[02:11] I tend sometimes to be accused of nihilism with regard to the origin of Homo because my view is we actually know nothing about the origin of Homo." This sets the tone for a discussion that emphasizes the limitations of the existing fossil evidence. The speaker likens the fossil record to a fragmented puzzle, asserting that the evidence available is akin to "[03:36] a car wreck" where only parts of the vehicle can be identified, making it challenging to reconstruct a comprehensive evolutionary history.

Furthermore, it is highlighted that the fossil record of the genus Homo from the period between 2 and 2.5 million years ago is alarmingly sparse. The speaker notes, "[10:58] It would fit in a shoe box and leave room for a decent pair of shoes," indicating the profound scarcity of evidence that complicates the understanding of early human evolution. The speaker stresses that this scarcity has led to ongoing debates and differing interpretations within the scientific community about the lineage and characteristics of early Homo species.

Overall, this suggests that while there are hypotheses surrounding the evolution of the genus Homo, the lack of concrete fossil evidence means that many questions remain open, and the scientific community must continue to explore new sites and gather more data to fill these gaps.

• [02:11] "I tend sometimes to be accused of nihilism with regard to the origin of Homo because my view is we actually know nothing about the origin of Homo."
• [03:36] "This is what we have to solve, this is the problem we have to solve and this comes from field work..."
• [10:58] "It would fit in a shoe box and leave room for a decent pair of shoes."

The transcript discusses various scientific debates within the field of anthropogeny, particularly regarding the evolutionary origins of the genus Homo. The speaker presents a view that there is a lack of consensus regarding the adaptive packages that characterize early members of the Homo lineage. Specifically, the speaker states, "[07:44] there is not one adaptive package that can describe them all, but there are perhaps multiple ones," indicating a divergence in hypotheses about how different species of Homo might have evolved and adapted to their environments.

Additionally, the debate extends to the identification of a common ancestor for the various Homo species. The speaker asserts that while there may be a monophyletic group of species around 2 million years ago, the exact nature of their shared ancestry and the characteristics of their environment remain contentious. The speaker mentions the impact of global climatic changes on the evolution of hominids, suggesting that ecological factors played a significant role in shaping the evolutionary path of Homo species, stating, "[09:02] information from global climate change, paleo-climatic change, has made it clear that..."

Furthermore, the speaker addresses debates regarding whether the genus Homo emerged as a result of specific environmental conditions, such as the drying out of Africa. They emphasize that while these hypotheses are prevalent, the lack of fossil evidence complicates the narrative. This ongoing discussion highlights the complexities involved in tracing human evolutionary history and the different interpretations that scientists have regarding the relationships and characteristics of early human ancestors.

• [07:44] "there is not one adaptive package that can describe them all, but there are perhaps multiple ones."
• [09:02] "information from global climate change, paleo-climatic change, has made it clear that..."
• [10:01] "This has become the prevailing hypothesis that the complexification... is all associated with the local impacts of these global changes."

[00:00] - [Recording] This UCSD-TV program is presented by University of California
[00:05] television. Like what you learn? Visit our website or follow us on Facebook and
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[00:19] ♪ [music] ♪
[00:23] - [Narrator] We are the paradoxical ape: bipedal, naked, large-brained. Long the
[00:31] master of fire, tools and language, but still trying to understand ourselves.
[00:38] Aware that death is inevitable yet filled with optimism. We grow up slowly. We hand
[00:48] down knowledge. We empathize and deceive. We shape the future from our shared
[00:56] understanding of the past. CARTA brings together experts from diverse disciplines
[01:03] to exchange insights on who we are and how we got here. An exploration made possible
[01:11] by the generosity of humans like you.
[01:30] ♪ [music] ♪
[02:00] - [William] Good afternoon everyone and thank you to the organizers here of CARTA
[02:06] for inviting me to participate and thank all of you, a great crowd, for coming out
[02:11] to see this fascinating topic explored. I tend sometimes to be accused of nihilism
[02:18] with regard to the origin of Homo because my view is we actually know nothing about
[02:25] the origin of Homo, just saying. And the reason is simple in my view; is that while
[02:37] it is true that we have a pretty good fossil record of the genus Homo, the Homo
[02:43] lineage as Bernard just finished explaining, by around 2 million years ago
[02:48] with some diversity and different adaptive packages in different species: erectus,
[02:57] habilis, rudolfensis. On the assumption that these three forms shared a common
[03:06] ancestor at some point. That common ancestor lived older than 2 million years
[03:12] ago in a period of time in which we have not a fender and a tire and a piece of
[03:20] gear shift, but in which we have a fragment of tire thread, which we have a
[03:28] fragment of a headlight. And we are trying to reconstruct an evolutionary history of
[03:36] a group for which we basically have a car wreck. And this is what we have to solve,
[03:45] this is the problem we have to solve and this comes from field work and I'm going
[03:50] to illustrate for you today in my view where I think the genus, the Homo lineage
[03:56] arose and where we have to re-double our efforts for increasing the representation
[04:02] of this lineage older than 2 million years ago. Now, as Bernard ably suggested, the
[04:10] modern history of the study of the evolution of the genus Homo really begins
[04:15] with Louis Leakey and colleagues and the recognition of the species, Homo habilis
[04:23] in 1964 based on material from Bed I in Olduvai Gorge dated to between around 1.7
[04:27] and 1.75 million years, they discerned in the type specimen of the species older by
[04:34] Hominid VII what they thought was a human-like dexterous ability in the hands,
[04:39] they discerned a notable increase in endocranial volume, brain size, in
[04:44] relation to then known Australopithecus species, mostly from southern Africa and a
[04:51] reduction in tooth size which they saw as emblematic of an overall gracilization of
[04:57] the chewing apparatus in almost a human-like arrangement. And putting these
[05:03] three characteristics together with the plentiful stone tools that had been
[05:06] recovered for years in these sediments, they arrived at the conclusion that this
[05:11] species, habilis, belonged near the base of the genus Homo. So convinced were they
[05:19] of this conclusion that Philip Tobias, one the co-authors of the species, was able to
[05:23] write in 1965 that Homo habilis represented that last remaining major gap
[05:29] in the pleistocene evolution of the genus Homo, "of the story of human evolution, "
[05:33] to quote him directly. And in this phylogeny shown here from one of Tobias'
[05:38] papers, you can see the genus Homo is represented as a single, gradually
[05:45] evolving line characterized by uniquely human characteristics related to large
[05:54] brain size, reduced canine teeth, a perfection of bipedal locomotion as we now
[06:01] see it, a slowing down of the growth trajectory, technology, language and so
[06:07] forth. This was a package of characteristics seen in modern humans and
[06:12] thought to go back in time to at least 2 million years as an integrated whole,
[06:20] along this slowly emerging lineage culminating in Homo sapiens. The problem
[06:26] was of course is that older than 2 millions years ago, there was virtually no
[06:31] fossil record that could be confidently associated uniquely with our lineage. And
[06:38] so whether these characteristics emerged piecemeal, step-wise and therefore each
[06:44] demanding a separate explanation for origin, or whether they emerged as a
[06:48] package together, where one explanation would take care of them all, could not be
[06:54] discerned. Now a lot has happened, as Bernard has pointed out in the years since
[07:00] early 1960s. And beginning in the 1980s, in large part due to the work that he and
[07:06] others have done in those years, we now see the genus Homo as a much more
[07:11] complicated array of species. In my view, there are at least three broadly
[07:20] contemporaneous forms present at around 2 million years ago whereas in 1964, the
[07:27] Leakeys would have said there's one in the genus Homo: Homo rudolfensis, Homo habilis
[07:33] and Homo erectus. And one of the lessons that we have learned from the appreciation
[07:39] of greater diversity in our own genus at this period of time, is the idea that
[07:44] there is not one adaptive package that can describe them all, but there are perhaps
[07:49] multiple ones. And the question is which, if any, are germane to the origin of the
[07:55] lineage itself? Or, are they all, in one form or another, subsequent developments
[08:01] to the establishment of the lineage? Following on Bernard's talking about
[08:08] Toyotas and clades, my appreciation, my rendering of the information available
[08:15] from these three forms between around 1.7 and 2 million years ago is that they do,
[08:22] in fact, constitute a monophyletic group. This is not the place to go into a
[08:27] detailed rendition about the evidence for it, but I think it speaks fairly clearly
[08:32] to the idea that these three at 2 million did in fact share a single unified
[08:37] ancestry predating that time period, moving back towards the 3 million year
[08:44] mark. And the question is, where is it? And who was it? And here's where we run up
[08:50] against a roadblock. Now, why is this important more than just for the purposes
[08:56] of putting cladograms or phylogenies on the page is because in the last decade or
[09:02] two, information from global climate change, paleo-climatic change, has made it
[09:09] clear that the tim period in which many people suspect the Homo lineage arose was
[09:14] one of a very widespread, impactful change in global climate, creating an expansion
[09:24] of ice sheets, reduction in sea levels, drying out of the African interior. And
[09:31] that time period has been focused right after the 3 million year mark; 2.8, 2.7
[09:38] and so forth. And that drying out of Africa has been seen as motive in the
[09:48] origin of the robust Australopithecines, the origin of the genus Homo, even to
[09:55] stone tool manufacture. This has become the prevailing hypothesis that the
[10:01] complexification, if you will, of hominids and the origin of technology is all
[10:06] associated with the local impacts of these global changes. The problem is that
[10:12] there's no fossil evidence for the genus Homo that is informative on exactly what
[10:18] those changes were at this particular point in time. We do have of course
[10:24] Oldowan tools at around 2.6 million. And as Bernard and others have pointed out,
[10:31] perhaps that is a proxy for the genus Homo or maybe it isn't. It's not outside the
[10:38] realm of possibility given what we know about how chimpanzees can make tools that
[10:42] some Australopithecus is capable of making them, too. So, questions and an absence of
[10:49] evidence. And here is the sum total of the fossil record of the genus Homo between 2-
[10:58] and 2.5 million years ago. It would fit in a shoe box and leave room for a decent
[11:04] pair of shoes. All of these fossils have been promoted by one person or another,
[11:14] one group or another as identifying the genus Homo older than 2.0 million years
[11:19] ago and all of them have been doubted. And I'm not going to go through them here to
[11:24] point out the weaknesses and strengths of the various arguments, other than to say
[11:29] that the very fact that there's debate can be traced to the fact that there's
[11:34] relatively little evidence. And this is why groups return to Africa, go to the
[11:42] field to African sites, in East Africa, in South Africa all the time focusing on this
[11:47] time period which, in my view, is one of the most intriguing of all the time
[11:51] periods in human evolution to increase our understanding of the fossil record. One
[11:57] area where the group from The Institute of Human Origins which I direct at ASU has
[12:03] been focusing on, of course, for years is Ethiopia. We've worked at the Lucy site
[12:09] more or less continuously since 1990. And colleagues of mine, Dr. Kaye Reed at ASU
[12:15] and Chris Campisano and others, have expanded the work, the IHO work in
[12:19] Ethiopia, to a place called Ledi-Geraru as seen here as slightly north and east of
[12:24] the Hadar area. What attracted them to this area? Two things, knowledge that the
[12:31] environments represented by the sediments in this area looked different from those
[12:37] that were very common and well-understood in the Lucy time period, older than 3
[12:43] million, some 20, 30 kilometers away at Hadar. And second, the suspicion verified
[12:50] since then that the rocks may actually represent a slightly younger time period
[12:55] and that's important because at Hadar, as you will see, we have Lucy species,
[13:00] Australopithecus afarensis up to about 3 million years and then we jump across
[13:05] three quarters of a million years and we have a jaw of Homo with some stone tools
[13:09] at 2.3 million. Lucy, Homo; older, younger. Gap in the middle, let's try to
[13:17] fill it. And that was their mission. Now, in the lower Awash Valley, these areas
[13:25] around Hadar and middle Ledi and Gona and Dikika and Woranso-Mille, there are
[13:31] excellent sediments going backwards in time from around 3 million years ago. And
[13:39] we have an excellent set of sediments in places like Gona and Hadar that take us
[13:43] forward from around 2.5 million years ago. It is the time period in between that is
[13:51] critical and is germane to the questions about where the three forms of Homo that
[13:56] we know of at 2 million perhaps emerged from? And these sediments are present
[14:03] amply, now well-studied in the Ledi-Geraru area spanning in time from around 2.8
[14:12] million years to about 2.6 million years. And what's really important to understand
[14:18] about these sediments, and this is both an advantage and a disadvantage is that they
[14:23] are not continuous across time, but instead are exposed in fault blocks,
[14:31] adjacent fault blocks which means that each block of sediment is a unified slice
[14:37] of time separated from another block next to it which has itself a unified period of
[14:43] time with slight gaps in between them. Disadvantaged because we can't trace
[14:49] evolutionary events continuously but advantage because fossils that come,
[14:54] demonstrably come, from particular fault blocks can be narrowed to a very narrow
[15:00] range of environments and associations with other animal species, etc. So, a plus
[15:05] and a minus. And here is the Ledi-Geraru area. Kaye and her team have been working
[15:12] her for more than a decade before they found their first hominid. Looking at the
[15:16] fauna, looking at the geology, trying to understand the environments. And by the
[15:22] way, this is an area called the Lee Adoyta basin and you can see here, here's one
[15:27] fault block, here's another fault block, and here's a third fault block. They're
[15:32] about three or four fault blocks just exposed in this one view, very clearly
[15:37] delineated. You can see one of the faults running right through here. Now, back in
[15:42] 2013, Kaye and her group of paleontologists were surveying an area in
[15:46] the Lee Adoyta basin called the Gurumaha block just in the one fault block. And at
[15:52] the base of this one hillside, there's a volcanic ash that is now well-dated, very
[15:58] precisely dated to 2.8 to 2, plus or minus a handful of years, in the million year
[16:05] range. And on one winter's day, one of our graduate students at ASU, Chalachew
[16:13] Seyoum, was surveying up on this hillside and found this little jaw. That jaw eroded
[16:22] out of this hill, perhaps in a recent rain storm and resides about 10, maybe 12
[16:28] meters above that volcanic ash. And on the hillside, there are no sediments up above
[16:35] younger that the jaw could have floated down from. It eroded out of that hillside
[16:42] and it's around 10 meters above the tough. So here's the jaw after it has been
[16:47] cleaned up. And I'm here to tell you that it answers some questions, answer some
[16:54] very specific questions. It doesn't answer all the questions. But there's a myth out
[17:01] here in Paleoanthropology that unless you have a complete skeleton, you're not
[17:07] prepared to answer any meaningful questions and I wish to dispel that myth.
[17:11] You know, since Raymond Dart named Australopithecus in 1925, there have been
[17:16] a plethora of hominid species named, recognized; Australopithecus africanus,
[17:24] Paranthropus robustus, Paranthropus boisei, Homo Habilis, on and on. Many of
[17:30] them, if not most of them on the basis of material that we here today would
[17:34] consider, at best, imperfect. A fragment of a jaw, a bit of a brain case, some
[17:40] teeth, and the fact of the matter is is that in the intervening years, the vast
[17:46] majority of those species recognized on the basis of imperfect material have been
[17:51] verified as to be meaningful evolutionary units. We are not at sea when we have
[17:57] small fragments. We are limited in the type of questions we can ask. If complete
[18:02] skeletons were the answer to all of our questions, then Lucy would have settled,
[18:08] once and for all, the debate about when early humans made a commitment to
[18:16] terrestrial bipedality. Instead, she generated what is now going on to five
[18:21] decades of debate about that question. It depends on the question and this question,
[18:28] the question that we address to this jaw, is it the same thing as Australopithecus
[18:33] at 2.8 million or is it something different? And I engaged in that question
[18:38] with my former PhD student, Brian Brian Villmoar now at University of Nevada, Las
[18:42] Vegas, and Chalachew Seyoum our graduate student who found the jaw. And we came to
[18:50] the conclusion that in many respects, it differs from your standard issue
[18:54] generalized Australopithecus jaw. Seen here on the left is a nice jaw of Lucy's
[19:00] species, Australopithecus afarensis and on the right is a reconstructed from a scan
[19:05] of the specimen from Ledi-Geraru. We noticed that the jaw differs
[19:11] rather...these two jaws differ rather remarkably. The afarensis jaw is typically
[19:16] long and narrow with fat molar teeth, primitive pre-molars and so forth. And our
[19:24] major comparison was to something like this, one of the jaws from the Dmanisi
[19:30] site dated to about 1.8 million years which is attributed to Homo erectus. And
[19:36] there's a much greater similarity in the shape of the dental arch, in the form of
[19:40] the teeth, the pre-molars being symmetrical and so forth, to this 1.8
[19:45] million year old Homo erectus jaw than to Lucy's species. And it extends also to the
[19:53] architecture of the jaw and I'm not going to go into the details here, but
[19:56] underneath the pre-molar, the afarensis jaw is characterized by a highly sculpted
[20:01] out, contour like a chimpanzee probably due to the very large canine teeth absent
[20:07] in the Ledi-Geraru jaw. The back part of the mandible where the vertical part
[20:13] called the ascending ramus arises from the body of the jaw is located in the Ledi jaw
[20:18] well back of the third molar, not forward as it is in Lucy's species over the second
[20:24] molar. And the upper and lower boundaries of the mandibular borders beneath the
[20:31] teeth and at the base are more or less parallel. And in Australopithecus, they're
[20:38] not, it gets shallower to the rear. And by the way, it's also true of
[20:42] Australopithecus africanus which is slightly closer in age to the Ledi jaw in
[20:47] South Africa, the same kind of thing. So, when we made the comparison to jaws of the
[20:54] genus Homo, later in time obviously because we don't have much in the 2.5 to 3
[20:59] million year period, the similarities were very apparent to us. This is a jaw that
[21:05] exhibits characteristics that forecast anatomy that is common, the most common
[21:14] anatomical patterns in jaws of the genus Homo younger than 2 million. So we
[21:19] published it, in not quite a year ago, in the Journal of Science as a 2.8 million
[21:24] year old jaw of the genus Homo. Now does it answer questions about what were the
[21:30] adaptive packages present early on in the lineage leading to us? Of course. But what
[21:37] it does do is that it puts one data point in an area that is otherwise a void in the
[21:45] evolution of our own genus. Question is what kind of environment did it live in?
[21:53] Did it live in a dry environment? Did it live in an open one? Germane to the
[21:57] questions about what drove early evolution of Homo. And data that's been put together
[22:03] by Kaye Reed and given to me for this purpose shows that this jaw is found in a
[22:11] context of animal species that lived in essentially grassland environments, very
[22:19] different in terms of how open or closed the habitats were compared to time periods
[22:28] in which Lucy's species lived. And this is just a couple hundred thousand years
[22:34] later. Now, I hasten to add here, I am not asserting that the origin of the genus
[22:41] Homo is due to a drying out of the environment. But one thing we can say,
[22:46] because of the very confined time period of the Gurumaha fault block in which the
[22:52] mandible and the fauna on which this inference is made, suggest that the modal
[22:57] environmental signal at 2.8 in this area is one essentially of a grassland
[23:03] environment. And we can see that by looking at some of the other animal
[23:09] fossils that have been found associated with the horizon from which that mandible
[23:14] has come. This is the Gurumaha block, these are El Salafin bovid frequencies and
[23:20] the horse frequencies, both of which of course are well-known grazers. And
[23:24] together, in the Gurumaha block, they constitute nearly 40% of the macrofauna,
[23:30] excludes elephants and hippos and stuff. I'm not saying it's dry, we're saying it's
[23:34] open. So it's 40% of the macrofauna and that is very impressive compared to the
[23:40] frequencies back in Lucy's time starting just 200,000 years earlier. Opens up areas
[23:48] for inquiry. And finally, some new data coming out of Kenya from Sonia Harmand's
[23:55] group suggests that stone tool use, in fact, began not with the genus Homo,
[24:02] maybe. But perhaps as long ago as 3.5 million years when we have
[24:09] Australopithecus. And if these finds are verified, it opens up a whole new range of
[24:16] possibilities looking at the adaptive packages that constitute the ancestral
[24:22] platform from which the genus Homo emerged. And so to finish up, here we have
[24:30] Ledi-Geraru, here we have our formerly first appearance, a former first
[24:34] appearance of stone tools now pushed back here perhaps and does that imply that the
[24:40] genus Homo itself has even an earlier origin than we think of at 2.8, perhaps
[24:47] back as far as Lucy? Or could Lucy herself have been the first stone tool maker?
[24:53] Thank you.
[24:56] ♪ [music] ♪

In this presentation, the speaker expresses gratitude for the audience's presence and acknowledges the pleasant weather in Chicago, humorously suggesting that it is always like this. The discussion begins with a reflection on the term "human," which the speaker's mentor, Michael Day, insisted should be qualified. The speaker emphasizes the need for clarity in defining what is meant by "human," whether it refers to an individual, a member of the species Homo sapiens, or a broader classification within the genus Homo. This sets the stage for a deeper exploration of human evolution, particularly focusing on the genus Homo.

The speaker takes the audience back to 1964, a significant year marked by the Civil Rights Act, the Beatles' rise in music, and a warning from the Surgeon General about smoking and cancer. This historical context is juxtaposed with the scientific landscape of human evolution at the time, where only a few taxa were recognized in the hominin fossil record. These included African taxa, Homo erectus primarily found in Asia, and Neanderthals and Heidelbergensis from Europe. The speaker recalls their own learning experience about human evolution during this period, highlighting the limited understanding of the time.

In 1964, a pivotal discovery was made by the Leakeys, who unearthed a cranium known as "nutcracker man" or Zinjanthropus boisei. This discovery was crucial as it introduced a new species into the conversation about human evolution. The speaker describes the cranium and its distinctive features, including a strange molar tooth that was initially puzzling until the cranium was found. On April 4, 1964, a groundbreaking paper was published in Nature by Lewis Leakey and his colleagues, Philip Tobias and John Napier, which proposed a new species of the genus Homo from Olduvai Gorge. This paper redefined the genus Homo, suggesting that it included a new, primitive species, Homo habilis.

The speaker delves into the implications of this redefinition, noting that it was a dramatic proposal that suggested a new understanding of human ancestry. The discussion highlights the significance of the cranium of Zinjanthropus boisei, which was initially thought to be the maker of stone tools. However, the discovery of Homo habilis, which appeared to have a larger brain and more advanced features, shifted the narrative. The speaker explains how the interpretation of skeletal remains, including a foot skeleton and hand bones, led to the conclusion that Homo habilis was a dexterous biped capable of tool-making.

As the presentation progresses, the speaker addresses the criteria for defining a genus, particularly in the context of Homo. The first criterion discussed is that all species within a genus must belong to the same clade, meaning they share a recent common ancestor. The speaker uses an analogy of car makes, specifically Toyota, to illustrate the concept of a clade. Just as all Toyota cars descend from a common ancestor, so too must all species within a genus share a recent common ancestor.

The second criterion involves the concept of a grade, which refers to the adaptive features shared by species within a genus. The speaker explains that all members of a genus should occupy a similar ecological niche or adaptive zone. This analogy is further illustrated with the example of four-wheel-drive vehicles within the Toyota brand, which represent a specific adaptive grade while still belonging to the broader clade of Toyota cars.

The speaker emphasizes the challenges faced by paleoanthropologists in reconstructing the evolutionary history of hominins, likening it to trying to piece together a complex puzzle with limited evidence. The discussion highlights the difficulty of establishing clear criteria for the genus Homo, particularly as new fossil evidence emerges. The speaker notes that while Homo sapiens is the type species of the genus Homo, the inclusion of other species, such as Neanderthals and Homo erectus, complicates the classification.

As the presentation continues, the speaker reflects on the historical context of the genus Homo and how the criteria for inclusion have evolved over time. The initial classification of Homo erectus as the most primitive member of the genus was challenged by the discovery of Homo habilis, which prompted a reevaluation of what constitutes a member of Homo. The speaker raises questions about whether the criteria for inclusion have been relaxed too much, potentially undermining the coherence of the genus.

In discussing the evidence that has emerged since 1964, the speaker notes that the Leakeys continued to discover more specimens that supported the classification of Homo habilis. These included associated skeletons that provided further insights into the morphology and behavior of early hominins. The speaker highlights the importance of associated skeletons in understanding the evolutionary relationships among species, despite the challenges posed by fragmentary remains.

The speaker also addresses the ongoing debate regarding the adaptive features of Homo habilis compared to other hominins. They suggest that while Homo habilis may have shared some traits with Australopithecus, it also exhibited characteristics that aligned more closely with later members of the genus Homo. This raises questions about the adaptive significance of Homo habilis and its role in the evolutionary lineage leading to modern humans.

As the presentation nears its conclusion, the speaker emphasizes the need for caution in interpreting the fossil record and the origins of the genus Homo. They argue that the origin of Homo is likely to be earlier than the first appearances recorded in the fossil record, highlighting the limitations of our current understanding. The speaker encourages the audience to remain skeptical of conventional wisdom and to recognize the complexities involved in reconstructing human evolutionary history.

In closing, the speaker pays tribute to Frank Brown, a geologist who contributed significantly to the field of paleoanthropology and the Leakey Foundation. They express gratitude to the audience for their attention and patience, acknowledging that the discussion may have been lengthy but is essential for understanding the intricate history of human evolution.

The transcript discusses several hominin species and human-like groups, detailing their evolutionary significance and contextual background. Here’s a comprehensive list of the mentioned species along with relevant information regarding their time periods and geographical locations:

• Homo habilis: Identified as one of the earliest members of the genus Homo, Homo habilis was dated to approximately 1.8 million years ago. This species was discovered at Olduvai Gorge in Tanzania, which was a significant site for early hominin fossils.
• Homo erectus: Mentioned as the most primitive member of the genus Homo prior to the identification of Homo habilis. It was primarily known from Asia and is recognized as a pivotal species in human evolution.
• Zinjanthropus boisei: Referred to as “nutcracker man,” this species was notably part of the discussion around stone tool usage and was found at Olduvai Gorge, although its exact dating was not specified in the transcript.
• Neanderthals: Discussed as a member of the genus Homo, Neanderthals are noted for their distinctive anatomical features, although the transcript does not specify exact dates or locations for their findings.
• Australopithecus: The speaker mentions that some fossils may belong to this genus but does not elaborate on specific species or dates.

Overall, the transcript emphasizes the significance of Olduvai Gorge as a central location for these discoveries, illustrating the evolutionary timeline and geographical diversity of early hominins.

• [10:45] "...homo habilis was dated one of it was one of the first hominins to be dated using potassium argon dating..."
• [21:30] "...the proposal in 1964 that there was an even more primitive creature in the genus homo that relaxed the criteria even more..."
• [39:42] "...the origin of homo is sometime before the earliest evidence for it..."

This transcript outlines several central claims regarding the process of human evolution, focusing particularly on the redefinition of the genus Homo and the implications of newly discovered species. Key assertions include:

• Redefinition of the Genus Homo: The speaker discusses a significant proposal made in 1964 to redefine the genus Homo to include Homo habilis, which was suggested to be the most primitive species in this genus. This redefinition stemmed from the discovery of fossil evidence that indicated a more complex evolutionary history.
• Brain Size and Cognitive Development: The transcript indicates a common assumption that brain size increases were pivotal in the evolution of Homo, particularly around 1.8 million years ago. This claim suggests that cognitive capacities evolved alongside physical changes, leading to more sophisticated tool use and social behaviors.
• Behavioral Adaptations: The emergence of Homo habilis is linked to tool-making capabilities, which signifies a behavioral adaptation crucial for survival and resource acquisition. The speaker mentions that this species had a larger brain and dexterous hands, which facilitated the development of complex tools.
• Environmental Adaptation: The discussion also touches on how evolving dietary patterns reflected in stable isotope analysis suggest shifts in habitat use and feeding strategies between Homo habilis and later species like Homo erectus.

These points reflect a nuanced understanding of human evolution, highlighting the interplay between anatomical changes, behavioral adaptations, and environmental contexts.

• [19:15] "...homo sapiens is the type species of the genus homo even though there is no type specimen of homo sapiens..."
• [22:09] "...if you're a paleontologist you come up with a hypothesis..."
• [26:22] "...the inclusion of habilis changed sort of destroyed the adaptive coherence of homo..."

The speaker references various types of data and evidence to support their claims regarding human evolution. Key forms of evidence include:

• Fossil Evidence: The discussion heavily relies on fossil discoveries, particularly from Olduvai Gorge. Notable mentions include Homo habilis, which was dated to approximately 1.8 million years ago, and the associated skeleton OH 62, which is partially fragmented but provides insight into the anatomy of early hominins.
• Dating Techniques: The use of potassium-argon dating and magnetostratigraphy as methods to establish the age of fossils is highlighted, indicating that Homo habilis is one of the earliest hominins dated using these techniques, showcasing advancements in dating methods during the time.
• Stable Isotope Analysis: The speaker mentions stable isotopes to infer dietary habits, suggesting that changes in carbon isotope ratios reflect dietary shifts from Homo habilis to Homo erectus. This type of evidence supports claims of evolutionary adaptation in response to environmental changes.
• Comparative Studies: There are indirect references to comparative studies with other primates, particularly in assessing anatomical features such as brain size, dexterity, and locomotion, as well as behavioral traits associated with tool use.

These forms of evidence collectively contribute to the understanding of human evolution, illustrating the complex interplay between physical changes and environmental adaptations.

• [10:27] "...one of the first hominins to be dated using potassium argon dating..."
• [26:19] "...the inclusion of habilis changed sort of destroyed the adaptive coherence of homo..."
• [39:00] "...it's racingly certain that all the tracks are in that diagram were around before the bottom of their column..."

The transcript reflects a nuanced understanding of the limitations and uncertainties inherent in the field of paleoanthropology. The speaker discusses the challenges of reconstructing evolutionary history, emphasizing the scarcity of evidence that scientists must contend with. This fragility of the fossil record is underscored by the speaker's statement that paleoanthropology is a "difficult science" rather than a hard or soft science, indicating that the field operates under conditions of uncertainty.

Moreover, the speaker points out that the evidence available is often incomplete, likening the search for fossils to a "drunk person looking for their keys under a lamppost," suggesting that researchers primarily focus on well-explored areas, such as the Rift Valley, which may not represent the full picture of human evolution. This analogy highlights the potential gaps in the fossil record, as significant portions of Africa remain unexplored.

Additionally, the speaker notes, "the origin of Homo is sometime before the earliest evidence for it," which implies that the scientific community acknowledges that current fossil evidence may only represent a snapshot in time, lacking the broader context needed for a comprehensive understanding of human origins. This awareness of limitations is crucial for ongoing research, as it sets the stage for future discoveries that may fill existing gaps in knowledge.

• [18:06] "...we have to deal with this picture... in other words we have to reconstruct the equivalent of the history of the toyota motor company using little scraps of evidence."
• [45:28] "...the origin of the genus homo like all origins related questions is challenging to answer scientifically."
• [22:11] "...if you're a paleontologist you come up with a hypothesis... and then people find more fossils and those fossils are either consistent with your hypothesis or they're not..."

The transcript reveals a rich tapestry of ongoing scientific debates within the field of anthropogeny, particularly regarding the classification and evolutionary relationships among early human species. The speaker highlights a significant discussion surrounding the inclusion of Homo habilis in the genus Homo, positing that this inclusion may have weakened the criteria for defining the genus. This debate raises questions about the adaptive coherence of the genus, as the speaker asks whether the addition of Homo habilis renders the genus less coherent.

Moreover, the speaker references competing hypotheses regarding the evolutionary significance of various hominin fossils discovered over time, noting that the criteria for inclusion in the genus have been relaxed. This relaxation is compared to a tennis club that initially has strict membership standards but ultimately lowers its criteria to maintain membership. The speaker points out that this shift has resulted in a more inclusive definition of the genus, which may lead to inconsistencies regarding the traits and behaviors expected of its members.

Additionally, the speaker discusses the implications of new fossil evidence, which could either support or challenge existing hypotheses about the evolutionary lineage of modern humans. The discourse surrounding the age and classification of early Homo species, especially in relation to Homo erectus and Homo habilis, illustrates the complexity of establishing direct ancestor-descendant relationships. The ongoing nature of these discussions highlights the dynamic and often contentious character of scientific inquiry in paleoanthropology.

• [27:16] "...there was an argument to be made that homo habilis should not be included in the genus Homo..."
• [20:25] "...you relax the criteria a little more and you still say it's a tennis club..."
• [21:24] "...the question I want to ask really in this lecture is were those criteria relaxed more than they should have been..."

[00:02] thank you very much
[00:04] thank you for coming um thank you for
[00:06] arranging for a
[00:08] wonderful day and
[00:11] i gather chicago is like this 365 days
[00:15] in the year
[00:19] i the word
[00:22] human my mentor
[00:26] a man called michael day would never let
[00:29] me use it without qualifying it
[00:32] do you mean an individual human being
[00:36] do you mean a member of the species homo
[00:39] sapiens
[00:40] do you mean a member of the genus homo
[00:43] or do you mean
[00:45] a a member of the part of the tree of
[00:48] life that leads to modern humans
[00:50] so he would never let me use it without
[00:52] some qualification
[00:53] and of course that means that i never
[00:55] let my students use it without some
[00:57] qualification
[00:58] and it drives them mad but i want to use
[01:01] the word human this evening in the sense
[01:03] of
[01:05] whether something is a member of the
[01:07] genus homer
[01:09] and um and in order to do that i need to
[01:12] take you
[01:13] um to back to 1964.
[01:18] um so it was the year of the civil
[01:21] rights act
[01:25] this is one i couldn't resist um it was
[01:27] the year that
[01:28] the beatles had um songs that were in
[01:31] the top
[01:31] five of the of the billboard
[01:35] top 40. um
[01:38] it was the year that elizabeth taylor
[01:40] and richard burton got married for the
[01:41] first
[01:42] time
[01:45] and it was the year that the surgeon
[01:48] general
[01:48] issued a warning about the possibilities
[01:50] of a link between
[01:52] smoking and cancer in other words it was
[01:54] quite a long time ago
[01:58] and in those days um these were the taxa
[02:02] that were
[02:03] recognized in the hominin fossil record
[02:06] um
[02:07] there were some african taxa
[02:10] and there was homo erectus that was
[02:12] mainly known from
[02:14] from asia there was homoredesiensis that
[02:16] was
[02:18] it was obviously an african taxon there
[02:21] was attacks on court homo helmei
[02:23] and then neanderthals and
[02:25] heidelbergensis from europe
[02:27] so that was what i had to learn um
[02:32] when i did a course on human evolution
[02:34] in
[02:36] in those days just um
[02:40] 1964 was just five years after the
[02:43] leakys had um
[02:45] um had
[02:50] the leakys had recovered a cranium
[02:54] that they called nutcracker man or
[02:57] zinganthropus boisei
[03:00] and that's a remarkable creature you can
[03:02] see the
[03:03] the cranium here and you can see um
[03:07] a strange molar tooth that they didn't
[03:10] know what it was until they found the
[03:12] cranium and thought
[03:13] maybe that's this strange molar tooth
[03:15] belongs to the creature
[03:17] that the the cranium belongs to
[03:21] and then in 1964 or at least on april
[03:25] 3rd 1964
[03:28] the oldest member of the genus homo and
[03:30] the most primitive member of the genus
[03:32] homo
[03:33] was homo erectus which was mainly known
[03:35] from asia
[03:39] then on april the 4th 1964
[03:44] this paper was published in nature
[03:47] and it says a new species of the
[03:49] genocomo from older by gorge
[03:51] from the same place that zagatopus
[03:54] boisei had been found
[03:57] and it was by lewis leaky and a
[04:00] colleague of his
[04:01] who he had asked to describe that
[04:04] wonderful cranium from
[04:07] um zinjanthropus boisei a man called
[04:09] philip tobias
[04:11] and john napier who was a colleague
[04:15] of bob's and mine in the university of
[04:18] london and a very distinguished
[04:19] primatologist
[04:23] and what they did in that paper was that
[04:26] they
[04:26] revised the diagnosis of the genus homo
[04:30] so let me try and unpack that for you
[04:32] they sort of
[04:33] redefined homo
[04:38] so what i want to do this evening is
[04:41] just to consider what led up to that
[04:43] proposal because that was a pretty
[04:45] dramatic proposal
[04:47] we're going to redefine the genus that
[04:50] all modern humans belong to
[04:53] and we are suggesting
[04:56] that we are describing
[05:00] a new species and the and the basal
[05:03] species the most
[05:04] primitive species in the genus homo
[05:08] so what led up to that was that the
[05:11] craniums in jantipus boisei was called
[05:13] aldebar hominid 5.
[05:16] okay you come from chicago so you must
[05:18] realize that ultima hominin 3 was
[05:20] discovered with
[05:22] before alder by hominin 5 and ultima
[05:25] hominid 4 was discovered before older by
[05:27] hominin 5.
[05:29] and all dubai hominid 4 was
[05:32] as the little sort of scraps of teeth
[05:36] that they really didn't sort of know
[05:39] what to do with and while they were
[05:41] considering these
[05:42] which they were extremely pleased to
[05:44] have just
[05:45] just a few weeks later they discovered
[05:47] this cranium so they
[05:49] you if know discover a cranium
[05:53] you stop worrying about a couple of
[05:55] teeth so they stopped worrying about a
[05:57] couple of teeth
[05:58] and then they discovered their age six
[06:02] i don't have my driving lesson my
[06:04] driving license for this
[06:06] machine so they discovered oh
[06:10] six were which is just a few pieces of a
[06:13] cranium
[06:16] and then they discovered a little more
[06:20] of a different cranium
[06:22] and then a mandible here
[06:27] and they began to realize that this was
[06:29] a creature
[06:30] that was unlike zinjanthropus boisei
[06:34] gingentropus boisei is a creature with a
[06:38] flat wide face with a crest down the
[06:41] middle of the cranium
[06:42] with huge teeth huge molar teeth
[06:46] this was a different sort of animal
[06:50] now in 1959 when they found zinc
[06:52] anthropos boisei
[06:55] this was the first hominin they had
[06:57] found which was the same age as the
[06:59] stone tools that they have been
[07:00] recovering
[07:02] so they thought zinc antibes poisoning i
[07:04] must be the maker of the stone tools
[07:08] sergeant xinjanthropus boisei had a
[07:11] rather short career
[07:13] as the maker of the stone tools because
[07:15] in 1964 they thought
[07:18] this is a better candidate for the maker
[07:21] of the stone tools
[07:23] why was it a better candidate because it
[07:25] seemed to have a bigger brain
[07:28] it seemed to have a bigger brain and so
[07:31] they
[07:32] said to you know zinc antibes boisei
[07:36] sorry uh we found a better
[07:40] a more likely maker of the stone tools
[07:44] and they also found the skeleton of a
[07:48] foot and they interpreted the skeleton
[07:51] of the foot as being the skeleton of a
[07:53] striding
[07:57] a biped biped and you must realize that
[08:01] at the authors john napier was a brit
[08:05] and in britain when we walk we strive
[08:12] i've always been struck by this notion
[08:14] that it's a striding biped
[08:16] it's a it's a stock broker on the way to
[08:20] the stock exchange or it's a banker on
[08:22] the way to the bank of england
[08:24] so so it not only had a larger brain
[08:29] it was interpreted as being a striding
[08:31] biped
[08:33] and there were some hand bones and they
[08:35] interpreted those hand bones as being
[08:38] as being dextrous the
[08:42] the hand of a dexterous creature
[08:46] so they put all these inferences
[08:48] together
[08:50] and and so they call this creature homo
[08:53] habilis
[08:54] habile capable of making things
[08:59] and so they said you know this was the
[09:01] creature that was making
[09:03] the tools
[09:07] and they also had some other specimens
[09:10] oh 13
[09:12] and they had this rather fragmented
[09:16] cranium
[09:17] that are pretty reasonable or at least
[09:20] pretty reasonable for 1.8 million
[09:22] years set of teeth
[09:25] so this was the material that they wrote
[09:29] about
[09:30] in this article in nature and there's
[09:32] louis leakey who always had a grin on
[09:34] his face
[09:36] and philip tobias who has rather a
[09:38] questionable taste in sweaters
[09:42] and john napier and they
[09:45] and these three people were the authors
[09:47] of the the paper
[09:50] the paper is called a new species of the
[09:52] genus homo from older by gorge
[09:58] so um so on april the 4th 1964
[10:04] and the other thing that happened was
[10:05] that ultimate gorge wasn't just a source
[10:08] of fossils it was also a place
[10:12] where new dating methods were tried out
[10:15] and were found to be successful
[10:18] and so um aldevi gorge
[10:21] the the material homo habilis was
[10:25] was dated one of it was one of the first
[10:27] hominins to be dated using potassium
[10:29] argan dating
[10:30] and it was one of the first hominids to
[10:32] be dating using mag
[10:34] using what's called magneto stratigraphy
[10:39] and so it had the surprising age of
[10:41] about 1.8 million years
[10:45] so this was a sort of a double whammy
[10:47] okay we found a new species of homo
[10:50] and it's 1.8 million years ago by the
[10:52] way
[10:54] substantially older than anything that
[10:56] had been found before
[11:00] so so having confused you with all that
[11:03] information
[11:04] i want to spend the rest of my time
[11:05] asking a question so what is a genus
[11:09] and which taxer shall be included in our
[11:12] own genocomo and why
[11:15] and then when and where did the the
[11:18] genus homo begin so i want to try and
[11:20] answer those questions
[11:22] and in doing so i'm going to draw on
[11:24] research of
[11:25] of of graduate students who were my
[11:28] graduate students in the past
[11:30] or um who are current graduate students
[11:33] eve boyle mark collard andrew do and
[11:35] david patterson
[11:38] so what is a genus well this is
[11:40] something that mark
[11:42] collard and i thought long and hard
[11:45] about and we thought you could just go
[11:47] to you know any one of
[11:50] many evolution textbooks and there would
[11:53] be a nice sort of definition of the
[11:55] genus
[11:56] actually it turned out that there were
[11:58] lots of definitions of the genus
[12:00] so we had to sort of sort through all
[12:03] these definitions and use our own grey
[12:05] cells and say well you know
[12:07] what is a jealous and
[12:10] and there were two criteria it seemed to
[12:12] me uh
[12:15] there were two criteria it seemed to us
[12:17] and the first was that the species needs
[12:19] to be in the same
[12:19] clade also known as a monophyletic group
[12:23] which i'm sure has helped you
[12:25] um as the type species of the
[12:28] prospective genes and the clade i will
[12:30] try and explain
[12:32] what that is using an analogy in a
[12:34] minute
[12:37] so that converts into a definition in
[12:39] other words all of the taxa
[12:41] no more and no less than our
[12:45] that are uh descended from a recent
[12:47] common ancestor
[12:48] so that's what a that's what a clade is
[12:52] so i'm going to use most of the
[12:54] amusement of my colleagues who
[12:57] think i'm obsessed with cars which i'm
[12:59] not
[13:00] i'm going to use the example of a make
[13:03] of car
[13:04] as an illustration of what a clade is
[13:08] and the an example i'm i'm going to use
[13:11] is the
[13:13] toyota motor company
[13:17] which which emerged from a company
[13:19] called toyota
[13:21] that made equipment to to manufacture
[13:25] material
[13:27] and the japanese had no
[13:31] car industry themselves so they decided
[13:34] that the toyota company
[13:37] should start to make cars
[13:40] and they did and this is the
[13:43] the prototype of the first toyota
[13:48] toyota and this is the first car and it
[13:51] was made in 1935.
[13:55] so that is the common ancestor of all
[13:59] toyota cars
[14:03] okay and we know because somebody's
[14:06] written the history of the toyota motor
[14:08] company
[14:10] and so it's the same as all of the taxi
[14:14] no more or no less in other words you
[14:16] can't have a nissan
[14:18] okay and you can't leave out any toyotas
[14:22] because it's the whole nine yards is the
[14:25] whole shooting match
[14:27] and the recent common ancestor is the
[14:29] prototype car
[14:32] the second criterion for a genus we
[14:36] suggested that it needs to be the same
[14:38] grade
[14:40] so what's a grade so it's a clade is
[14:43] like a make of car what's a grade
[14:46] so it needs to be in the same grade in
[14:48] other words its
[14:49] way of living needs to be closer
[14:53] to it's it's a group of animals that are
[14:57] doing more or less
[14:58] the same thing disregard the mumbo jumbo
[15:02] on the slide
[15:04] so it's a group of taxa that shares a
[15:06] suite of adaptive
[15:11] features in other words all the members
[15:14] of a journalist need to be in the same
[15:16] adaptive zone
[15:19] so back to motor cars
[15:24] one of the great successes of the second
[15:26] world war was the willis
[15:29] jeep and so the japanese decided that
[15:32] they would make a japanese version of
[15:35] this
[15:36] jeep so in 1951
[15:40] instead of making passenger cars they
[15:42] made a four-wheel
[15:43] drive vehicle and this is called
[15:46] it was called the bj so within the
[15:50] toyota clade
[15:54] there is a subgroup of toyotas which are
[15:57] four-wheel drive vehicles they can go
[16:00] places that
[16:01] two-wheel drive vehicles can't
[16:05] and so they are a new adaptive grade
[16:08] yet they're in the toyota clade
[16:12] and so i'm going to suggest to you that
[16:14] four-wheel drive
[16:16] toyota vehicles are a good example
[16:21] of something that's equivalent to a
[16:23] genus
[16:25] they are all sort of adaptively coherent
[16:29] and they're all made by the same motor
[16:31] car company
[16:34] and there are people who spend their
[16:36] life
[16:39] worrying about the history of of of
[16:42] four-wheel drive cars made by
[16:46] toyota and so here is a diagram of
[16:50] the evolution of four-wheel drive
[16:54] passenger vehicles made by
[16:58] toyota and i'm going to ask you or at
[17:00] least
[17:01] suggest to you that it's a good analogy
[17:04] for a a genus
[17:08] one of the reasons we need the leaky
[17:10] foundation is of course
[17:12] for the toyota motor company it's pretty
[17:14] easy because there are people who
[17:15] remember what happened
[17:18] and the toyota motor motor company has
[17:20] some historians who work for the toyota
[17:22] motor company so they record all these
[17:24] things
[17:27] and there are people who have nothing
[17:28] better to do who
[17:30] spend their time on the internet writing
[17:33] about
[17:34] the the history of the toyota motorcycle
[17:36] i shouldn't say because there may be
[17:37] somebody here who's
[17:38] who's an expert on the toyota motor
[17:40] company and it's it's a perfectly
[17:42] wonderful thing to do
[17:43] and thank goodness people have done it
[17:45] otherwise i couldn't do this
[17:48] but our problem is that
[17:53] that instead of this picture
[17:57] we have to deal with this picture
[18:01] in other words we have to reconstruct
[18:03] the equivalent of the history of the
[18:04] toyota motor company
[18:06] using little scraps of evidence
[18:10] and there is nobody writing it down and
[18:14] that's the challenge and that's why
[18:15] paleoanthropology
[18:17] and bob martin i remember very well
[18:22] i'm not sure whether it was in this
[18:24] rather mindless class about how to
[18:26] lecture
[18:27] but uh but um
[18:30] but in those days there was
[18:34] there was a sort of a category of hard
[18:36] sciences things like
[18:38] chemistry and physics and softer
[18:41] sciences
[18:43] things like economics and things like
[18:44] that and bob said
[18:47] you know the problem is that we work in
[18:48] a difficult science
[18:50] it's not hard it's not soft it's just
[18:53] really difficult because you're trying
[18:55] to recover evolutionary history
[18:57] and there's not a lot of evidence so
[19:01] so if a genus needs to be a clade and a
[19:03] grade
[19:04] which taxes should be included in the
[19:06] genus homo
[19:08] and why well
[19:11] um homo sapiens is the type
[19:15] species of the genus homo even though
[19:18] there is no
[19:19] type specimen of homo sapiens
[19:23] uh but it's the type species so that has
[19:26] to be included in the genus hemo
[19:30] when the anatoles were discovered they
[19:33] were suggested that that species
[19:36] should be added to the genotymo
[19:39] so it's like sort of taking a modest
[19:41] sized car
[19:43] and you know which looks like homo
[19:45] sapiens and then you know neanderthals
[19:47] are different they have
[19:49] different shaped cranium different sort
[19:53] of
[19:54] different shaped teeth but nonetheless
[19:56] they sort of live their lives
[19:58] much like modern humans live their lives
[20:01] so you're making the genus homo a little
[20:04] more inclusive
[20:06] it's a bit like having a tennis club you
[20:08] know and you start with great
[20:09] aspirations that in order to belong to
[20:11] this tennis club you have to
[20:12] you know be this good at tennis and then
[20:14] you discover there are only nine people
[20:16] who are that good at tennis and you
[20:17] realize that
[20:18] that doesn't make for a very vibrant
[20:20] club so you say okay
[20:22] we'll relax our criteria and we'll you
[20:25] know let other people join
[20:29] then with the inclusion of what was
[20:31] pathetic anthropos erectus and
[20:33] sinantropus pekinensis into the
[20:34] genocimal
[20:37] homo became even more inclusive
[20:41] and so the criteria for joining the
[20:43] tennis club were relaxed even more
[20:45] you know can you hold a tennis racquet
[20:50] do you know which bit to hold okay
[20:54] so so so you relax the criteria a little
[20:58] more and you
[20:58] but you still say it's a tennis club
[21:03] then and so that
[21:06] the situation in 1944
[21:11] was that that homo erectus was the most
[21:15] primitive member of the genus hammer
[21:18] then with the proposal in 1964
[21:21] that there was an even more primitive
[21:24] creature in the genocima
[21:27] that relaxed the criteria even more
[21:30] and the question i want to ask really in
[21:32] this lecture is were those criteria
[21:35] relaxed
[21:37] more than they should have been in other
[21:39] words does the inclusion of homo habilis
[21:42] in the genus homo
[21:44] render the clade criterion
[21:47] mute and does it render the grade
[21:50] criterion
[21:51] in other words does it sort of destroy
[21:54] the adaptive
[21:56] coherence of of the genus homo
[22:02] so how did the 1964 proposal
[22:07] withstand the test of evidence because
[22:09] because if you're a paleontologist you
[22:11] come up with a hypothesis
[22:13] this is you know how i think the world
[22:15] is organized and looks
[22:17] and then people find more fossils and
[22:19] those fossils are either consistent with
[22:21] your hypothesis
[22:23] or they're not in which case
[22:26] your hypothesis bites the dust and
[22:29] somebody comes up with a different
[22:30] hypothesis
[22:31] that's how that's how this historical
[22:35] science works
[22:38] so after 1964 the leakys found more
[22:41] specimens
[22:43] from alta by gorge which they thought
[22:46] were consistent
[22:47] with these new specimens
[22:50] belong to homo habilis
[22:54] they found an associated skeleton
[22:57] now an associated skeleton is
[23:00] a is um is a specimen
[23:04] that preserves more than one element of
[23:07] the postcranial skeleton as well as
[23:10] maybe some teeth or jaws
[23:13] now the good news is that oh 62 is an
[23:16] associated skeleton
[23:18] there is there is a piece of humerus and
[23:20] some forearm bones and a bit of the
[23:22] femur
[23:23] and the proximal tibia the bad news is
[23:26] is that it's been in a serious road
[23:27] traffic accident
[23:30] and so oh 62 is really fragmented the
[23:34] cranium is is in lots of pieces lots of
[23:37] the teeth are in lots of pieces
[23:39] so the good news is that it's an
[23:41] associated skeleton the bad news is that
[23:44] it's a highly fragmented one but
[23:45] nonetheless
[23:47] that palette looks nothing like the
[23:50] palette of oh
[23:52] five which is the type specimen of
[23:54] xinjiangtopus boisei
[23:56] so that also probably belonged to homo
[23:59] habilis
[24:01] and then this is material that we were
[24:03] finding
[24:04] in in northern kenya
[24:08] and this was also suggested that it
[24:10] might belong to homo habilis
[24:13] and then material was found from from
[24:15] sites in
[24:17] southern africa and they were suggested
[24:19] that it was suggested that they also
[24:21] belong to herma habers
[24:25] one of the jobs i was given as as a
[24:27] member of the kubifora
[24:30] research group was to try and make sense
[24:33] of all the cranial remains that were
[24:34] discovered at ku before and this is
[24:37] the book that um that if you really
[24:40] can't sleep
[24:41] this is the solution to your problems
[24:46] and what i suggested was that it's
[24:49] most likely that the material
[24:54] that was discovered sampled
[24:57] not one but
[25:01] two species but what i suggested was
[25:04] that
[25:04] the leakys were probably right leaky
[25:06] tobias and napier were probably right
[25:09] that even though there was some evidence
[25:11] that there were two species of homo
[25:13] represented
[25:14] at kubifora and in the shangri-formation
[25:18] in
[25:18] in the omo there was no evidence that
[25:21] there was more than one sort of early
[25:23] homo at aldeba
[25:25] so homo habilis was good and the
[25:28] question was were the two species of
[25:30] qibifura was one of them homo habilis
[25:34] or were they two new species of early
[25:36] homo
[25:37] and if one of them was homo habilis what
[25:39] the hell was the other one
[25:43] so um so how did this new evidence
[25:47] affect the clade and the grade
[25:50] definitions of a genus well as far as
[25:52] the clade
[25:53] definitions of a degeneracy
[25:58] the new evidence made not that much
[26:00] difference
[26:02] but as far as the grade criteria was
[26:04] concerned
[26:06] mark collard and i suggested that the
[26:09] inclusion of habilis
[26:12] changed sort of destroyed the adaptive
[26:16] coherence of homo
[26:19] and we set out the case for that in a
[26:22] paper in science in
[26:24] 1999 called the human genus
[26:26] imaginatively called the human genus
[26:30] and what we did was to look at various
[26:33] criteria
[26:36] things like body size and body shape and
[26:38] inferred locomotion
[26:40] and the size of the jaws and teeth and
[26:42] the rate of development
[26:45] and brain size and basically it's not
[26:48] surprising that uh
[26:49] neanderthals get an h for homo for all
[26:52] of those things
[26:54] homo height against this there's not a
[26:56] lot of evidence but there are some h's
[26:58] and one a
[26:59] for australopithecus homo erectus gets
[27:02] h's
[27:04] homogasta gets ages but homo habilis got
[27:06] a lot of a's for australopithecus
[27:09] so we suggested that
[27:13] there was an argument to be made that
[27:16] homo habilis
[27:17] should not be included in the genocima
[27:20] it was a
[27:21] it was it was a you know it was a great
[27:23] idea at the time
[27:25] but nonetheless the years that had
[27:28] passed between 1964 and 1999
[27:32] the hype the the hypothesis that habilis
[27:35] should be included in homo
[27:38] it seemed to us that it had been
[27:40] substantially weakened
[27:43] um what i need to say was that it seemed
[27:46] to us that it had been substantially
[27:47] weakened but almost nobody took any
[27:49] notice of what we said
[27:52] even though i still think we were right
[27:54] and i i will try and persuade you that
[27:56] we were right
[27:58] so we suggested that homo
[28:01] it was quite right to have stopped the
[28:05] tennis club
[28:08] um the performance relaxation at the
[28:11] bottom of homo erectus
[28:14] and so we suggested that uh
[28:17] that the two species of early homo
[28:19] should actually be
[28:21] be um should actually be included in
[28:24] australopithecus as australopithecus
[28:26] um habilis and australopithecus
[28:27] rudolfensis but this went down like the
[28:30] proverbial
[28:31] lead balloon so what has happened since
[28:36] 1999 well there's been more fossil
[28:38] evidence
[28:40] and that's the sort of thing that the
[28:41] leaky foundation
[28:45] that the funding from the leaky
[28:46] foundation allows to happen
[28:49] and this is new fossil evidence from
[28:53] this jaw from from uh from kubifora
[28:59] and then miss maxilla
[29:02] and basically the new fossil evidence
[29:04] the good news
[29:05] uh for bernard wood was that the notion
[29:08] that there were two species in
[29:09] la homo was consistent with this new
[29:12] fossil record
[29:13] uh with this new fossil evidence the bad
[29:16] news is that i
[29:17] might have got some of the allocations
[29:19] slightly wrong
[29:20] okay that may be a jaw that i thought
[29:23] belonged to henry
[29:25] may actually belong to herman hablis but
[29:27] in general
[29:29] you know the news was you know the
[29:31] balance of the news for me was good
[29:35] that doesn't happen very often
[29:38] the other thing that's happened since
[29:40] 1999 is that there has been a proposal
[29:43] that the genus homo goes back in time um
[29:47] to 2.8 million years on the basis of
[29:49] this mandible found from a site
[29:52] at lady guerraru in ethiopia
[29:56] so the other thing that's happened since
[29:57] 1999
[29:59] is that and basically
[30:03] what i do is try and now what i do is
[30:07] analyze
[30:08] the fossils that other people find
[30:13] and so what you need is
[30:16] more fossils there's no doubt about that
[30:19] but you need to get smarter at analyzing
[30:21] the fossils that you do find
[30:24] there's no point in just finding more
[30:25] fossils and not developing methods
[30:28] there's no point in developing methods
[30:29] if you don't find new fossils
[30:34] you need both of those things
[30:37] so there has been new evidence since
[30:40] 1999
[30:41] new methods of of really
[30:44] crawling all over the fossil evidence
[30:46] trying to extract
[30:48] more and more information from it
[30:51] some of that new evidence involves
[30:53] inferences about body shape some of it
[30:55] involves inferences about locomotion
[30:58] some about cognition some about
[30:59] dexterity some about diet and some about
[31:02] life history
[31:05] the inferences about locomotion that
[31:06] have been made since 1999
[31:10] really backed up what mark collard and i
[31:13] said was that homo habilis
[31:14] probably was not moving around in the
[31:18] same way that homo erectus was homo
[31:20] erectus was an obligate biped
[31:22] homo habilis was capable of bipedalism
[31:25] but it was using its arms a lot more
[31:28] than you and i do
[31:29] to to move around as a biped
[31:34] there was also some evidence which is
[31:36] which has come up about cognition
[31:39] and of course we don't know anything
[31:41] about the cognition of hominins that
[31:43] lived millions of years ago but we make
[31:45] inferences about
[31:46] cognition based on their brain size
[31:49] um that's not you know but that's what
[31:53] we do
[31:53] whether we should do that is another
[31:55] matter but that's what we did
[31:59] and basically there's been some sort of
[32:01] conventional wisdom about brain science
[32:04] and and the conventional wisdom was
[32:08] that there was an increase in brain size
[32:10] that occurred about 1.8 million years
[32:13] ago
[32:14] which coincided with the origin of the
[32:17] genus homo if you included homo habilis
[32:19] in the genocima
[32:22] and so this diagram which was in a paper
[32:25] by leslie aiolo and peter wheeler has
[32:28] become sort of iconic to the extent
[32:31] that now in textbooks there is the
[32:34] generous
[32:34] homo burst of increase in brain size at
[32:37] 1.8 million years
[32:40] now like all conventional wisdom you
[32:42] should suspect it
[32:44] okay you should suspect it and c.h
[32:48] waddington
[32:49] um he referred to conventional wisdom as
[32:51] the conventional wisdom of the dominant
[32:53] group
[32:54] and his acronym really appeals to me
[32:56] it's cow dung
[33:00] conventional wisdom of the dominant
[33:02] group always suspect conventional wisdom
[33:04] so what we did what i did was
[33:08] was was to get a group of bright
[33:10] graduate students that was led by andrew
[33:12] dew
[33:13] who's now a postdoc at the university of
[33:14] chicago
[33:16] and said there are more data points
[33:19] but of course these are points
[33:23] and we know that you know if you're
[33:24] collecting information about something
[33:26] that's a couple of million years ago
[33:29] one point would suggest that there is no
[33:31] error
[33:32] and that's unlikely because often the
[33:34] endocranial volume
[33:36] the brain size is extrapolated on the
[33:39] basis of a rather fragmentary cranium
[33:43] and there is also some error in the date
[33:47] so probably you shouldn't have these
[33:50] points
[33:51] you should have a diagram that expresses
[33:53] the error
[33:55] that's involved in the measurement of
[33:57] the brain volume
[33:58] and the date and when you do that to cut
[34:02] a long story short
[34:04] and you test those data against various
[34:08] um um
[34:12] various evolutionary modes random warp
[34:14] gradualism stasis punctuated equilibrium
[34:17] because this
[34:18] genus homo burst was an example of
[34:20] punctuated
[34:22] was an example of of an event
[34:27] that that's called that's called a
[34:30] punctuation event
[34:32] in an otherwise equilibrium of brain
[34:34] size
[34:36] and when these guys did that they found
[34:40] that the data
[34:41] fitted far far far far better
[34:45] to a gradualism model then to
[34:48] an increase in brain size at 1.8 million
[34:51] years
[34:52] so that weakened the case
[34:56] for you know the 1.8 million years
[35:01] the other thing this is another student
[35:03] this is david patterson's work
[35:05] uh was looking at stable isotopes and
[35:08] stable isotopes you are what you eat
[35:13] and uh you can
[35:16] if you eat a lot of grass you have
[35:20] high levels you have levels which are
[35:23] called
[35:24] c4 okay if you eat a lot of leaves
[35:28] you have levels of stable isotope which
[35:31] is called
[35:32] c3 if you eat a mixture of grass and
[35:35] leaves
[35:36] you're a mixed feeder and so you're c3
[35:39] slash
[35:40] c4 okay
[35:44] if you're a grazer you're c4 if you're a
[35:46] browser like a giraffe or c3
[35:49] if you're an antelope that both grazes
[35:51] and browsers
[35:52] you're a mixed feeder
[35:55] you can look at these stable isotopes in
[35:58] the soil
[36:00] so not in not in the bones of animals
[36:02] but in the soil
[36:03] and when you do that you see
[36:07] that in lake turkana from 2 million
[36:09] years to about 1.3 million years
[36:12] there isn't much of a trend
[36:16] okay stays more or less the same
[36:19] so the wooded grassland signal
[36:23] sort of equivalent signal
[36:26] so what happens if you look at the
[36:29] isotopes in animals
[36:32] from this we would infer that there
[36:34] hasn't been a great deal of change in
[36:36] the environment
[36:38] in other words the animals what they
[36:41] could eat was much the same at 2 million
[36:44] years as it was at 1.3 million years
[36:47] so what happens if you look at the
[36:48] animals well if you look at
[36:52] a paranthropus boisei uh
[36:55] the early part of that time range is
[36:58] much the same
[36:59] as the later part of the time range and
[37:02] paranthropus boisei is a c4
[37:04] sort of type of animal and it's c4
[37:08] uh you know two million years and it's
[37:12] c4 at 1.3 million years it doesn't
[37:14] change
[37:16] whereas if you look at homo
[37:20] the early ones are
[37:23] c3 stroke c4
[37:27] and the c4 signal becomes stronger in
[37:31] the later ones
[37:32] these early ones are homo habilis stroke
[37:35] homo rude offenses
[37:36] that we were suggesting should not be in
[37:38] homo
[37:40] the later ones are our early african
[37:43] homo erectus
[37:44] which we suggested was a perfectly good
[37:48] member of the genocimal
[37:51] so what might be the explanation for the
[37:53] change in the stable isotope
[37:56] well we don't know but one explanation
[37:59] is
[38:00] that this c4 sort of grassland
[38:04] signal is because homos started to eat
[38:08] animals that were eating grass
[38:11] because you are what you eat and if you
[38:15] eat
[38:15] meat of animals that are grass eaters
[38:19] you inherit their grass signal
[38:23] now we don't know that that's the
[38:25] explanation but that's
[38:27] that's the explanation i would like it
[38:28] to be
[38:32] what's interesting
[38:35] is that homo is the only taxon that
[38:39] undergoes a significant enrichment in
[38:41] delta 13
[38:42] in carbon delta 13 through time
[38:47] all the other animals either stay the
[38:49] same or they become
[38:50] more c3 not c4
[38:55] so we think that's pretty good evidence
[39:00] that there is a shift between the way
[39:02] that homo habilis was making its living
[39:05] and the way that homo erectus or early
[39:07] african
[39:09] um um early african homo erectus was
[39:13] making its living so we
[39:14] think if there was a shift it wasn't
[39:17] from australopithecus to homo habilis
[39:21] because homo habilis has a stable
[39:23] isotope signature which is like
[39:24] australopithecus it was a shift between
[39:27] homo habilis and homo erectus
[39:30] so you will be relieved to hear i'm
[39:34] getting to the bottom of this slide
[39:36] so when did homo originate well
[39:42] we think it originated here and not
[39:45] there
[39:47] but what you have to realize is that
[39:49] these columns and this is a diagram that
[39:51] the bob was referred to or at least an
[39:53] updated version of it
[39:56] these columns are they represent a
[39:59] hypothesis about
[40:01] the existence of a taxon and they
[40:04] represent a hypothesis about
[40:06] well not a hypothesis they represent an
[40:09] observation
[40:10] about the first
[40:13] time we see that taxon in the fossil
[40:15] record and the last time we see that
[40:17] taxon in the fossil record
[40:20] so the existence of the taxon is a
[40:22] hypothesis
[40:24] the the bottoms of those columns isn't a
[40:27] hypothesis
[40:28] it's an observed fact and the tops of
[40:31] those columns is not a hypothesis
[40:33] it's an observed fact the fact that
[40:36] that's a separate species is of course a
[40:38] hypothesis
[40:39] so each column represents a hypothesis
[40:42] about the existence of a taxon
[40:44] and the ages of the existing site
[40:46] samples of that taxon
[40:51] but the observed first and last
[40:53] appearance dates of a taxon are
[40:55] just that they are not
[40:59] the first time that taxon walked on the
[41:01] earth
[41:02] or the top of the column is not you know
[41:06] but the last person standing of that
[41:09] taxon
[41:11] so so the column doesn't necessarily
[41:14] represent the beginning of the existence
[41:16] of the taxon it just represents
[41:18] its appearance in our fossil record so
[41:21] it's racingly certain
[41:23] that all the tracks are in that diagram
[41:25] were around before the bottom of their
[41:27] column
[41:28] and it's racingly certain they were all
[41:30] around uh
[41:31] um subsequent to the top of the column
[41:37] and there are different sorts of errors
[41:39] around
[41:41] the first appearance date and the last
[41:42] appearance stage
[41:44] depending on how many fossil sites there
[41:46] are how many fossils
[41:48] were discovered at those fossil sites
[41:50] and so on
[41:53] so what the columns are not are
[41:56] take to the bank statements about the
[41:58] timing of the origin
[41:59] and extinction of each taxon i cannot
[42:02] emphasize that too much
[42:05] so for example you can't say
[42:08] oh if the lady goraru mandible belongs
[42:11] to homo
[42:12] then homo begins at
[42:15] um 2.8 million years
[42:19] i should say not that you can't say
[42:21] because people do say it
[42:23] i'm saying you shouldn't say
[42:28] and so what i'm suggesting is that homo
[42:33] the origin of homo is sometime before
[42:37] the earliest evidence for it
[42:43] likewise if you think like us that uh
[42:46] the to that homo erectus is the earliest
[42:48] um is the earliest evidence of homo
[42:51] that's not the origin of the genome
[42:54] sometime before the earliest homo
[42:56] erectus fossil
[42:58] so the last question is where did homer
[43:02] originate
[43:04] well what you have to realize is is that
[43:07] africa is a big place i remember coming
[43:09] to the field museum a few years ago and
[43:11] there was an exhibit
[43:12] there was an exhibition about africa
[43:16] and they drew africa on the floor of the
[43:19] hall
[43:20] and they put other countries in africa
[43:23] to show just how damn large
[43:25] africa was and the problem is that
[43:28] the projections of the world that you
[43:30] see in atlases
[43:32] they systematically minimize the size of
[43:36] the countries
[43:37] closest to the equator that's just the
[43:39] way these projections work
[43:43] so you know i was really impressed
[43:45] because in africa was you know
[43:47] australia north america south america
[43:50] europe you know it's a big place okay
[43:53] africa is a big place
[43:54] and the fossil sites in africa
[43:58] the evidence for human evolution comes
[44:00] from sites in and around the rift valley
[44:03] and from a few sites here in the dominic
[44:05] limestone in southern africa
[44:06] and from sites in central africa at the
[44:10] most you can persuade yourself that
[44:11] that's three and a half percent of the
[44:13] land surface of africa
[44:15] so if you think that we know everything
[44:18] about human evolution
[44:20] by discovering what was happening in
[44:22] parts of three and a half percent of the
[44:24] surface of africa
[44:26] i'm sure anybody coming to this lecture
[44:29] would say
[44:29] that's probably unlikely okay that's
[44:32] really unlikely
[44:34] and the problem is you know it's it's
[44:36] the problem of the drunk and the keys
[44:39] you know the drunk person has dropped
[44:40] their keys
[44:42] whether they look for their keys they
[44:43] look for their keys under the lamppost
[44:46] not because that's where they drop their
[44:47] keys because the only place you can see
[44:51] and the only place we can see is the
[44:54] rift valley
[44:54] and the dolomatic and the caves and the
[44:56] dolomitic limestones
[44:58] but that doesn't mean that that's where
[45:00] the keys were dropped
[45:02] and so you have to realize that that you
[45:04] know we probably haven't
[45:06] sampled everything there is to know
[45:09] so given we cannot know what data we're
[45:11] missing
[45:13] what should we say about the origin of
[45:15] homo
[45:16] the answer is as little as possible
[45:22] really and i'm serious i mean you know
[45:24] as little as possible
[45:26] and the origin of the genus homo like
[45:28] all origins related questions
[45:30] is challenging to answer scientifically
[45:34] that doesn't mean it's not a legitimate
[45:37] question to ask
[45:39] but if you're a scientist you have to
[45:41] say i can't do everything
[45:43] you have a very interesting question but
[45:46] i can't answer it scientifically
[45:48] and our job is not to pretend that we
[45:50] can do things that we can't do
[45:53] there are a lot of people around at the
[45:54] moment doing that in spades
[45:58] and so we shouldn't sort of join them
[46:02] so i want to thank you for coming this
[46:04] evening and i just want to pay tribute
[46:06] to a colleague who died last year
[46:09] frank brown who was a geologist who
[46:11] worked in east africa and
[46:13] and he was really intimately connected
[46:15] with the leaky foundation
[46:17] and a lot of these columns the heights
[46:20] of those columns and the dates
[46:22] and the information that goes into
[46:24] assembling those columns
[46:26] it's due to frank and he's
[46:30] sadly missed so thank you for coming and
[46:33] thank you for your patience i know some
[46:35] of you
[46:36] expected to be home or having your
[46:38] supper now so
[46:40] thank you very much
[46:41] [Applause]
[47:05] you

The Evolution of Humanity: A Comprehensive Overview

The narrative of humanity's evolution is a complex tale that spans millions of years, beginning approximately seven million years ago when the human lineage diverged from that of chimpanzees. This pivotal moment set the stage for the emergence of various early human species, known as hominins, with over 20 distinct species identified throughout history. While many of these species ultimately faced extinction, some are believed to be direct ancestors of modern humans.

These hominins displayed a range of physical and behavioral traits that were increasingly human-like, including larger brain sizes, smaller teeth, bipedalism, and the use of tools. The evolution of hominins can be categorized into three major groups: early hominins, australopithecines, and the genus Homo. The earliest relatives of humanity, which existed between seven and 4.4 million years ago in Africa, retained many ape-like characteristics, such as smaller cranial capacities. However, fossil evidence indicates that some of these ancient hominins began to develop traits more akin to modern humans, such as smaller canines that were likely adapted for a diet rather than for hunting or fighting.

The subsequent phase of evolution introduced the australopithecines, who thrived between 4.4 and 1.4 million years ago across Africa. While they also retained some ape-like traits, significant changes in their skull, spine, and leg structures marked a transition towards consistent bipedal locomotion, a hallmark of human evolution.

The third and current phase of human evolution is represented by members of the genus Homo, with the earliest species dating back over two million years, coexisting with some australopithecines. Unlike their predecessors, Homo species exhibited increasingly human-like characteristics, including larger cranial capacities than any other hominins. They developed advanced stone tool technologies and were the first to harness fire, which played a crucial role in their survival and adaptation.

These physical and behavioral advancements, coupled with technological innovations, enabled certain Homo species to migrate out of Africa, leading to the exploration of new territories across the globe. Despite the existence of numerous hominin species throughout history, only one remains today: Homo sapiens. Shaped by millions of years of evolutionary processes, Homo sapiens embarked on a journey of exploration and industrialization that their ancestors could scarcely have imagined, marking a significant milestone in the story of life on Earth.

The transcript provides insights into several hominin species and human-like groups that played significant roles in the evolution of humanity. The key groups mentioned include:

• Early Hominins: These are the earliest known ancestors of modern humans, who lived between 7 and 4.4 million years ago in Africa. While specific species are not named, they are noted for having some ape-like characteristics, including a small cranial capacity.
• Australopithecines: This group thrived between 4.4 and 1.4 million years ago across the African continent. They exhibited a mix of ape-like traits and significant adaptations towards bipedalism, suggesting a critical evolution towards human-like locomotion.
• Genus Homo: The transcript refers to the earliest members of this genus, likely dating back to more than 2 million years ago, existing contemporaneously with some australopithecines. This group is characterized by a notable increase in cranial capacity and the development of sophisticated tools and the control of fire, marking a significant departure from earlier hominins.

Overall, the transcript indicates that while many hominin species have existed, only Homo sapiens remains today, having undergone millions of years of evolution.

• [00:17] 'The story of humanity's evolution began about seven million years ago when the human lineage broke away from that of chimpanzees.'
• [01:00] 'Humanity's earliest relatives lived between seven and 4.4 million years ago in Africa.'
• [02:14] 'The third and current phase of human evolution involves members of the genus homo.'

The transcript outlines several central claims regarding the process of human evolution, focusing on anatomical, behavioral, and cognitive developments that were pivotal for the emergence of modern humans. The key assertions include:

• Separation from Ancestors: The human lineage diverged from that of chimpanzees approximately seven million years ago, setting the stage for subsequent evolution.
• Diversity of Hominins: Over 20 early human species emerged, showcasing a range of physical and behavioral traits that contributed to their survival and adaptation.
• Evolution of Bipedalism: The australopithecines displayed significant anatomical changes, such as modifications in the skull, spine, and legs, which facilitated bipedal locomotion. This adaptation is crucial for the efficient movement of early humans.
• Advancements in Technology: Members of the genus Homo developed sophisticated stone tool technology and were the first to control fire, which were critical steps in human innovation and survival.
• Migration Out of Africa: The physical and behavioral adaptations of Homo species enabled them to be the first to migrate out of Africa and explore other parts of the world, marking a significant expansion of the human presence on the planet.

These developments collectively highlight the complex interplay between evolution and adaptation that has defined the human journey.

• [01:08] 'Each species exhibited varying degrees of human-like physical and behavioral traits such as large brains, small teeth, bipedality and tool use.'
• [02:42] 'Their cranial capacity was growing larger than any other hominins.'
• [03:04] 'These physical and behavioral adaptations, along with advancements in technology, allowed some homo species to be the first to migrate out of Africa.'

The transcript references various types of evidence that support the claims made about human evolution. While it does not delve into specific fossils, genetics, or archaeological finds in detail, it does allude to some key forms of evidence:

• Fossils: The mention of ancient hominins and their fossil records suggests that paleontological evidence plays a significant role in understanding the anatomical changes over time. For instance, the evolution from early hominins to australopithecines and finally to Homo species is inferred through fossil records that exhibit changes in cranial capacity and bipedalism.
• Comparative Studies: The transcript indicates a comparison with chimpanzees, the closest living relatives of humans, to illustrate the evolutionary divergence. This comparative approach highlights the shared characteristics and distinctive adaptations that characterize the human lineage.
• Technological Evidence: The development of sophisticated stone tools and the control of fire by Homo species serves as a form of archaeological evidence that marks significant technological and behavioral advancements in early human history.

While specific data or examples are not elaborated upon in the transcript, these references indicate the reliance on a variety of scientific methods to understand the evolutionary narrative of humanity.

• [01:40] 'The next phase of hominin evolution involved primates called australopithecines.'
• [02:09] 'Consistent bipedal locomotion.'
• [02:52] 'They developed sophisticated stone tool technology.'

The transcript does not provide explicit statements regarding the reliability, certainty, or quality of the data being discussed. It primarily focuses on the evolutionary journey of hominins and does not delve into the scientific community's confidence in the findings or the robustness of the fossil record. However, the mention of over 20 early human species suggests an acknowledgment of the complexity and richness of human evolution, which inherently implies a potential for gaps or uncertainties in the fossil record.

For instance, the transcript notes that most early hominins became extinct, and while some may have been ancestors to modern humans, it does not clarify how these relationships are established or the extent of evidence supporting them. As such, the absence of specific details on the available fossil evidence or scientific consensus regarding the evolutionary pathways leaves open questions about the fragility and scarcity of the evidence. The narrative implies a progression of understanding but does not emphasize the ongoing debates or challenges faced by researchers in reconstructing the human lineage.

In summary, while the transcript provides a coherent overview of human evolution, it lacks direct commentary on the certainty of the data or the limitations that may exist within the fossil record.

• • [02:32] "But unlike earlier hominins who exhibited a mosaic of ape and human-like traits."
  • [03:10] "While a cast of over 20 hominin species have walked this Earth only one remains."

The transcript does not explicitly mention any scientific debates, competing hypotheses, or disagreements within the field of anthropogeny. It offers a linear narrative that outlines the evolutionary trajectory of hominins without addressing any controversies or differing viewpoints regarding their classification, migration, or behavioral traits. Instead, the focus is largely on the chronological development of hominins, detailing the transition from early ancestors to modern humans.

However, it does highlight the existence of multiple hominin species and suggests that some of these species may have shared common ancestors with modern humans. The lack of specific discussions around migration routes, ancestor-descendant relationships, or behavioral traits indicates a missed opportunity to explore ongoing research questions or unresolved issues in the field. For example, while it mentions that some Homo species were the first to migrate out of Africa, the transcript does not elaborate on the implications of these migrations or any associated theories.

In conclusion, the transcript provides a rich narrative about human evolution but does not engage with the complexities or debates that characterize the scientific understanding of these topics. Thus, it presents a more educational overview rather than a critical examination of the current state of anthropogeny.

• • [01:57] "These hominins fell into three major groups."
  • [02:20] "The earliest homo species likely date to more than two million years ago."

[00:00] - [Narrator] Millions of years before industry,
[00:03] agriculture and civilization
[00:06] the world stage was set for one creature's
[00:10] unprecedented rise.
[00:17] The story of humanity's evolution
[00:20] began about seven million years ago
[00:22] when the human lineage broke away from that of chimpanzees.
[00:27] Over time an ensemble cast of over 20 early humans species
[00:32] or hominins came to the fore.
[00:36] Most became extinct
[00:38] while others might have been ancestors to today's humans.
[00:43] Each species exhibited varying degrees
[00:46] of human like physical and behavioral traits
[00:49] such as large brains, small teeth, bipedality and tool use.
[00:57] These hominins fell into three major groups.
[01:00] Early hominins, australopithecines, and homo genus.
[01:08] Humanity's earliest relatives
[01:10] lived between seven and 4.4 million years ago in Africa.
[01:16] Having most recently shared a common ancestor
[01:18] with chimpanzees they had many ape-like traits
[01:21] such as a small cranial capacity.
[01:24] However fossils show that some ancient hominins
[01:28] were also beginning to show human-like characteristics
[01:31] such as small canines that were likely used more for eating
[01:35] and not for hunting or fighting.
[01:38] The next phase of hominin evolution
[01:40] involved primates called australopithecines.
[01:43] They lived between 4.4 and 1.4 million years ago
[01:48] across the African continent.
[01:53] Like their ancient brethren
[01:55] australopithecines had some ape-like traits.
[02:02] However changes in the skull, spine and legs
[02:05] indicate a notable shift toward a very human-like trait.
[02:09] Consistent bipedal locomotion.
[02:14] The third and current phase of human evolution
[02:17] involves members of the genus homo.
[02:20] The earliest homo species likely date
[02:23] to more than two million years ago
[02:26] making them a contemporary of some australopithecines.
[02:32] But unlike earlier hominins
[02:34] who exhibited a mosaic of ape and human-like traits.
[02:37] Homo species were becoming distinctly more human.
[02:42] Their cranial capacity was growing larger
[02:45] than any other hominins.
[02:48] They developed sophisticated stone tool technology.
[02:52] And they became the first to control fire.
[02:56] These physical and behavioral adaptations
[02:59] along with advancements in technology
[03:01] allowed some homo species to be the first
[03:04] to migrate out of Africa and explore the rest of the world.
[03:10] While a cast of over 20 hominin species
[03:13] have walked this Earth only one remains.
[03:18] Homo sapiens shaped by millions of years of evolution
[03:22] embarked on a journey of exploration and industry
[03:26] its ancestors could have only dreamed.

In the video, the narrator discusses the existence of various human species that have lived on Earth before Homo sapiens, emphasizing that we are not the only human species to have ever existed. The video outlines approximately 13 different human species, each with unique characteristics and evolutionary significance.

The first species mentioned is Homo habilis, which lived between 2.4 and 1.4 million years ago in Africa. This species is noted for its ape-like features, including long arms and a cranial capacity that was less than half that of modern humans. Some researchers suggest that Homo habilis may have evolved into Homo erectus, the next species discussed.

Homo erectus thrived from 1.9 million years ago to about 143,000 years ago, originating in Africa and spreading to regions such as India, China, and Java. They were taller than Homo habilis, standing around 5 feet 10 inches, and had a greater cranial capacity. Their potential use of rafts for ocean crossing marks a significant advancement in human adaptability.

Next, the video introduces Homo gautengensis, characterized by large teeth suited for chewing plant materials. This species, believed to have lacked advanced speech and language skills, stood about 3 feet tall and spent considerable time in trees, indicating a lifestyle that combined terrestrial and arboreal activities.

Homo neanderthalensis, or Neanderthals, are highlighted as one of the most well-known extinct human species, appearing around 200,000 years ago in Eurasia. They shared many physical traits with modern humans and utilized sophisticated tools for hunting, as well as creating ornamental objects, suggesting a complex social structure.

Homo floresiensis, often referred to as "hobbits," lived from approximately 95,000 to 17,000 years ago in Indonesia. This species was notably small, around 3.5 feet tall, and exhibited unique physical traits such as large feet. Evidence suggests they made tools and hunted small game, linking them to local folklore.

Homo rudolfensis is noted for its larger brain case and massive teeth, existing around 1.9 to 1.8 million years ago. The physical characteristics of this species remain largely unknown due to limited fossil evidence.

Homo heidelbergensis existed between 700,000 and 200,000 years ago and is believed to have been the first to bury their dead and adapt to colder climates, showcasing early forms of social behavior and environmental adaptation.

The Denisova hominin, known from limited fossil remains found in Siberia, lived between 200,000 and 50,000 years ago. Their classification remains tentative due to the scarcity of evidence, yet they are recognized as a distinct group within the human lineage.

Homo naledi is another intriguing species, with a mix of modern and primitive traits, believed to have existed between 300,000 and 200,000 years ago in South Africa. Their brain size was comparable to that of a chimpanzee, raising questions about their cognitive abilities.

Homo ergaster existed around 1.4 million years ago and displayed physical traits similar to modern humans, including a smaller face and larger cranial capacity, indicating a gradual evolution towards more advanced human characteristics.

Homo antecessor, known as the "Explorer," lived in Western Europe between 1.2 and 0.8 million years ago. They exhibited traits such as potential right-handedness and developmental patterns similar to modern humans, suggesting a complex social structure.

Homo rhodesiensis, discovered in Zambia, is recognized for its robust skull and significant brow ridges, existing between 400,000 and 125,000 years ago. This species contributes to our understanding of human diversity in physical traits.

The video concludes with Homo sapiens idaltu, a subspecies of modern humans that lived around 160,000 years ago in Africa. They are believed to have evolved from Homo rhodesiensis and exhibit heavier brow ridges.

Finally, the narrator emphasizes that Homo sapiens are the last surviving species of the genus, characterized by advanced cognitive abilities, bipedal locomotion, and complex social structures. They first appeared in Africa about 200,000 years ago and have since spread globally, showcasing unparalleled technological and artistic advancements.

The video encourages viewers to engage with the content by liking, subscribing, and sharing their thoughts in the comments section, fostering a community interested in the history of human evolution.

The transcript identifies several hominin species, detailing their time periods and geographical locations. Below is a comprehensive list of the hominins discussed:

• Homo habilis: Lived between 2.4 to 1.4 million years ago, primarily in Africa.
• Homo erectus: Existed from 1.9 million years ago to approximately 143,000 years ago, originating in Africa and spreading to regions including India, China, Georgia, and Java.
• Homo gautengensis: Known for having lived in a timeframe that is not specified in the transcript; however, they are described as having certain physical adaptations.
• Homo neanderthalensis: Appeared in Eurasia approximately 200,000 years ago.
• Homo floresiensis: Lived from 95,000 to 17,000 years ago in Indonesia.
• Homo rudolfensis: Existed around 1.9 to 1.8 million years ago, with no specific location mentioned.
• Homo heidelbergensis: Lived between 700,000 to 200,000 years ago, with origins in Africa.
• Denisova hominin: Existed in Eastern Asia between 200,000 and 50,000 years ago.
• Homo naledi: Alive around 300,000 to 200,000 years ago in South Africa.
• Homo ergaster: Existed about 1.4 million years ago in Africa.
• Homo antecessor: Present in Western Europe, specifically Spain, England, and France from 1.2 to 0.8 million years ago.
• Homo rhodesiensis: Existed between 400,000 and 125,000 years ago in northern Rhodesia (now Zambia).
• Homo sapiens idaltu: Emerged around 160,000 years ago in Africa.
• Homo sapiens sapiens: The modern humans, who first appeared in Africa about 200,000 years ago and spread worldwide.

• [00:40] 'There are around 13 human species that have ever lived before us.'
• [01:40] 'They had a cranial capacity greater than that of Homo habilis.'
• [07:23] 'We the modern humans are the wise men, are the only extant members of the hominins.'

The transcript presents several central claims regarding the process of human evolution and highlights key anatomical, behavioral, and cognitive developments pivotal for the emergence of modern humans.

Firstly, it asserts that humans are not the only species to have walked the Earth, with around 13 human species existing before Homo sapiens. This underlines the evolutionary diversity and complexity of the human lineage. The speaker emphasizes that Homo sapiens are the only surviving species, categorized as the 'surviving species.'

Key anatomical features mentioned include:

• Cranial Capacity: Species like Homo erectus exhibited a cranial capacity greater than that of Homo habilis, indicating advancements in brain size and cognitive abilities.
• Physical Attributes: Species such as Homo heidelbergensis were characterized by a flatter face and larger brain cases, suggesting adaptations to their environments.
• Posture and Locomotion: The evolution of bipedalism is highlighted as a crucial adaptation for movement and survival.

Behaviorally, the transcript indicates that species like Homo neanderthalensis engaged in tool-making and symbolic activities, which suggests a level of cognitive sophistication and cultural development. The use of tools for hunting, along with the practice of burying the dead by Homo heidelbergensis, points to complex social behaviors.

Overall, the narrative of human evolution as portrayed in the transcript reflects a gradual accumulation of anatomical and behavioral traits that have defined modern humans.

• [00:15] 'The truth is that we are not the only human species to have ever lived.'
• [01:17] 'Some say that one population of Homo habilis might have evolved into the earliest undisputable human species, the Homo erectus.'
• [07:43] 'None seems to have been able to compete with our technological and artistic sophistication.'

The speaker references various types of evidence to support the claims made regarding human evolution and the existence of different hominin species. The types of data and evidence mentioned include:

• Fossils: Numerous species, such as Homo habilis, Homo erectus, and Homo neanderthalensis, are supported by fossil evidence that illustrates their physical characteristics and timeframes. For example, fossils found in Denisova cave provide insights into the Denisovans.
• Archaeological Finds: The mention of stone tools created by species like Homo floresiensis indicates archaeological evidence that reflects their ability to hunt and adapt to their environment.
• Comparative Studies: The transcript discusses the cranial capacities and physical features of various species in relation to each other, suggesting a comparative approach to understanding evolutionary relationships.
• Behavioral Evidence: The speaker highlights behaviors such as tool usage and burial practices, suggesting cognitive developments associated with these activities.

Despite the comprehensive nature of the evidence presented, the transcript does not mention genetic or DNA data explicitly, nor does it provide direct references to specific genetic studies or comparative genome analyses.

• [01:15] 'Some say that one population of Homo habilis might have evolved into the earliest undisputable human species.'
• [04:24] 'Fragments of their fossils were found in the remote Denisova cave in the Altai Mountains in Siberia.'
• [06:05] 'They had strange mix of features with some parts of its skeleton indistinguishable from those of living people.'

The transcript provides some insights into the reliability and certainty of the data it discusses, particularly regarding the scarcity of fossil evidence and the consequent uncertainties surrounding various human species. The speaker mentions that some species, such as Homo naledi, have uncertain age estimates, stating that, "[05:54] no official data has been published regarding the species age although unofficial reports suggest it was alive between 300 and 200 thousand years ago." This indicates a gap in the fossil record and a level of uncertainty within the scientific community about the timeline of this species.

Moreover, the transcript points out the challenges in categorizing certain species due to the fragmentary nature of the fossil evidence. For instance, the Denisovans are described as having a "[04:44] slight reluctance in giving them any scientific name yet in regards to being a part of a homo species" because so little is known about them. This reflects the ongoing challenges faced by researchers when it comes to accurately defining and understanding the relationships among various hominin species.

Overall, the transcript highlights the scientific community's acknowledgment of the limitations of current evidence and the ongoing work required to fill in the gaps in our understanding of human evolution. It suggests that while substantial progress has been made in identifying and understanding these ancient species, significant uncertainties remain.

• • [05:54] "no official data has been published regarding the species age although unofficial reports suggest it was alive between 300 and 200 thousand years ago."
• [04:44] "there's a slight reluctance in giving them any scientific name yet in regards to being a part of a homo species."

The transcript primarily focuses on outlining various human species and their characteristics without delving deeply into scientific debates or competing hypotheses. However, it does hint at underlying complexities in the field of anthropogeny, particularly concerning the relationships and evolutionary paths of different hominin species.

For example, the speaker mentions the Homo habilis as possibly evolving into Homo erectus, which could imply a debate regarding direct ancestor-descendant relationships between these species. The statement, "[01:15] some say that one population of Homo habilis might have evolved into the earliest undisputable human species, Homo erectus" reflects the uncertainty surrounding lineage and evolution. This suggests that there are differing views on how these species may be interrelated.

Furthermore, the transcript discusses the physical and behavioral traits of Homo neanderthalensis, noting their similarities to modern humans as well as their use of tools. This acknowledgment of shared traits may reflect a broader discourse on whether Neanderthals exhibited behaviors akin to those of modern humans, which is a subject of ongoing research and debate in the field.

While the speaker does not take a definitive side on these issues or present multiple perspectives explicitly, the mentions of potential ancestor-descendant relationships and behavioral traits of Neanderthals imply an awareness of the complexities and debates that exist in anthropogeny.

• • [01:15] "some say that one population of Homo habilis might have evolved into the earliest undisputable human species, Homo erectus."
• [02:42] "they are sometimes labeled past a cousin of our species that is because they had most of the features of modern humans."

[00:00] [Music]
[00:08] when we say humans most people think we
[00:11] are the only ones are the only species
[00:13] that have ever walked this earth but the
[00:15] truth is that we are not the only human
[00:17] species to have ever lived
[00:19] we are just the human species that
[00:21] survived hence we can call ourselves the
[00:23] surviving species welcome back to this
[00:26] channel guys in today's video we are
[00:27] going to talk about the various kinds of
[00:29] human species that have existed before
[00:31] us but before we start please remember
[00:33] to check our previous videos and hit
[00:36] like and subscribe
[00:37] there are around 13 human species that
[00:40] have ever lived before us all these have
[00:42] varying features but there are some
[00:44] characteristics that they have left
[00:45] behind in us so let us check them out
[00:48] number one Homo habilis of all the homo
[00:51] species this is the one that is the
[00:53] least similar to Homo sapiens in lift
[00:55] between 2.4 to 1.4 million years ago it
[00:58] evolves in Africa and when extinct in
[01:00] the same place they possess some
[01:02] ape-like features such as long arms a
[01:05] moderately
[01:05] pragmatic face and they had a cranial
[01:08] capacity slightly less than half of the
[01:10] size of modern humans some say that one
[01:13] population of Homo habilis might have
[01:15] evolved into the earliest undisputable
[01:17] human species the homo erectus number
[01:21] two Homo erectus they lived throughout
[01:23] the Pleistocene period from 1.9 million
[01:26] years ago to most recently 143 thousand
[01:29] years ago studies prove that homo
[01:31] erectus originated in Africa and spread
[01:33] through India China Georgia and then
[01:35] Java they had a cranial capacity greater
[01:37] than that of Homo habilis and it stood
[01:40] about 5 feet 10 inches tall and they
[01:42] were extraordinarily slender with long
[01:44] arms and legs it has been suggested that
[01:47] they may have been the first guys to use
[01:49] rafts to cross oceans number 3 homo goat
[01:54] and ganses fossils of this species show
[01:56] that they had big teeth to chew plant
[01:59] materials and most researchers believed
[02:00] that they lacked in speech and language
[02:02] skills especially due to the small brain
[02:04] the species was found to have stood over
[02:06] 3 feet tall and weighed about a hundred
[02:09] ten pounds researchers say they could
[02:11] walk on two feet when on the ground but
[02:13] most prof
[02:14] spend considerable time in trees perhaps
[02:16] feeding sleeping and escaping predators
[02:18] but besides all that they believed it
[02:21] was a very pretty close relative of Homo
[02:23] sapiens number four Homo
[02:25] neanderthalensis the Neanderthals were
[02:28] found to have appeared in Eurasia
[02:30] approximately 200,000 years ago they are
[02:32] the most famous of all the extinct human
[02:34] species that is probably the reason why
[02:36] the Big Bang Theory's team song was made
[02:39] based on them or included them they are
[02:42] sometimes labeled past a cousin of our
[02:44] species that is because they had most of
[02:45] the features of modern humans they
[02:47] looked the same they used different
[02:49] tools for hunting and was symbolic
[02:51] ornamental objects number five Homo
[02:54] floresiensis they were believed to have
[02:57] lived ninety five thousand years ago to
[02:58] 17,000 years ago in Indonesia also known
[03:01] as the hobbits
[03:02] they were quite small in size around 3.5
[03:04] feet tall with a tiny brain besides a
[03:06] short body and a small brain they had
[03:08] unusually large and long feet exactly
[03:11] like hobbits there are some evidences
[03:13] that tell us that this species made
[03:15] stone tools and used them to hunt small
[03:16] elephants and large rodents and they may
[03:19] be connected by folk memory to the EBU
[03:21] gogo myths of the Isle of Flores number
[03:25] six homo rudolfensis they are believed
[03:28] to have lived around 1.9 million years
[03:30] ago to 1.8 million years ago they
[03:32] displayed less prognathism and around
[03:34] the brain case then rather than a
[03:35] burning brain case it was found that a
[03:38] male hormone rudolfensis had massive
[03:40] teeth and compared to a female hobo
[03:41] habilis and it portrays a much larger
[03:44] brain case but their physical belt
[03:46] weight and height are still unknown due
[03:49] to the scarcity of cranium fossils
[03:51] number seven Homo heidelbergensis the
[03:55] lifts on earth between seven hundred and
[03:56] two hundred thousand years ago and was
[03:58] found that they emerged from africa the
[04:00] approximate height of the species was
[04:01] five feet five inches tall and weighed
[04:03] about 58 kilograms or slightly more than
[04:06] 120 pounds they had a large brain case
[04:08] with a flatter face than modern humans
[04:10] findings show that they might have been
[04:13] the first species to have buried their
[04:14] dead and also who were the first human
[04:16] species to adapt to colder climates and
[04:18] to build their own shelters to live in
[04:20] number eight Denisova hominin also known
[04:24] as the Denisovans possibly throughout
[04:26] eastern asia between about two hundred
[04:28] thousand years ago and fifty thousand
[04:29] years ago fragments of their fossils
[04:31] were found in the remote Denisova cave
[04:33] in the Altai Mountains in Siberia a cave
[04:35] which has also been inhabited by Homo
[04:38] Neanderthals and Homo sapiens all the
[04:41] modern humans because so little is known
[04:42] about them there's a slight reluctance
[04:44] in giving them any scientific name yet
[04:46] in regards to being a part of a homo
[04:49] species number nine homo Naledi found to
[04:52] have existed in south africa but no
[04:54] official data has been published
[04:56] regarding the species age although
[04:57] unofficial reports suggest it was alive
[04:59] between 300 and 200 thousand years ago
[05:01] they had strange mix of features with
[05:04] some parts of its skeleton
[05:05] indistinguishable from those of living
[05:07] people while other parts look almost
[05:09] caped like he also had a brain a little
[05:11] bigger than that of a chimpanzee number
[05:14] 10 Homo ergaster this species existed
[05:17] and remain stable for approximately
[05:19] 500,000 years ago in Africa before
[05:21] disappearing from the fossil records
[05:23] about 1.4 million years ago they had
[05:25] thinner bones more producer faces and a
[05:27] lower forehead the species had reduced
[05:30] sexual dimorphism meaning males and
[05:32] females were almost the same in size
[05:34] they were with a smaller face a smaller
[05:37] dental arcade and a larger cranial
[05:39] capacity overall their body was so much
[05:41] alike to a modern humans body number 11
[05:44] Homo antecessor it actually means
[05:47] Explorer and was known to have been
[05:49] present in Western Europe in Spain
[05:50] England and France between 1.2 million
[05:53] years ago and 0.8 million years ago they
[05:56] are about five feet five inches tall to
[05:58] six feet tall and males weighed
[06:00] approximately 90 kilograms studies say
[06:03] they might have been right-handed which
[06:04] is a trait that makes the species
[06:06] different from other Apes and based on
[06:08] teeth eruption pattern the researchers
[06:10] thing that they had the same development
[06:11] of stages as us Homo sapiens number 12
[06:15] homo rhodesiensis it was also named
[06:18] because they found it in northern
[06:19] rhodesia now Zambia it was also known as
[06:22] the Rhodesian man
[06:23] the skull was dubbed a rude Asian man at
[06:25] a time of the fine but it is now
[06:27] commonly referred to as the Broken Hill
[06:29] skull or the calf way cranium they were
[06:32] found to have the
[06:33] between 400 and 125 thousand years ago
[06:35] the skull found was from an extremely
[06:38] robust individual and was seen to have
[06:39] comparatively the largest brow ridges of
[06:42] any known permanent remains number 13
[06:45] the homo sapiens idaltu
[06:47] otherwise known as the herd to man are
[06:49] the firstborn they are the subspecies of
[06:52] Homo sapiens and never proximately
[06:54] 160,000 years ago in place to see in
[06:56] Africa they were discovered and a Herto
[06:59] buried near middle awash site of
[07:01] Ethiopia's afar triangle in 1997 by Tim
[07:04] white but were first unveiled in 2003
[07:07] they were said to have developed from
[07:09] the homo rhodesiensis and had heavier
[07:11] brow ridges number 14 homo sapiens
[07:15] sapiens lasts never the least and the
[07:18] last surviving species of the genus
[07:19] that's us we the modern humans are the
[07:23] wise men are the only extant members of
[07:26] the hominins glade we are characterized
[07:28] by erect posture bipedal locomotion
[07:30] larger complex brains and manual
[07:33] dexterity our species was said to have
[07:35] first appeared in Africa about 200,000
[07:37] years ago and spread across the rest of
[07:39] the world and none seems to have been
[07:41] able to compete with our technological
[07:43] and artistic sophistication anyway
[07:48] thanks for watching guys please support
[07:50] our channel by liking our videos and
[07:52] subscribing to the channel you can also
[07:54] tell us about your thoughts in the
[07:55] comment section
[07:57] [Music]

Introduction to Lucy and Her Significance

The video discusses the significance of Lucy, a pivotal fossil in the study of human evolution, marking her 50th anniversary since discovery. Lucy is considered a primitive ancestor, providing insights into the common lineage shared with chimpanzees. Discovered in 1974 by Don Johansson and Tom Gray, Lucy's age of approximately 3 million years was revolutionary, as it suggested a much earlier existence of hominins than previously believed.

Discovery Context and Initial Skepticism

Initially, the scientific community was skeptical about Lucy's classification as a member of the human family. Early researchers even speculated that she might be an early baboon. It wasn't until the 1950s that fossils from East Africa began to confirm the existence of human ancestors dating back at least 2 million years. The discovery of Lucy, however, marked a significant turning point in understanding human ancestry.

The Discovery Process

During the discovery, the conditions were challenging, with temperatures exceeding 100°F. Johansson's team found various fragments, including parts of the elbow, skull, and jaw, which led them to conclude that they had found an early hominin. The name "Lucy" was suggested by a team member, inspired by the Beatles song "Lucy in the Sky with Diamonds," although there was a desire to honor her Ethiopian roots with a local name, such as "Dinkes," meaning "you are wonderful."

Physical Characteristics and Evolutionary Implications

Lucy's physical characteristics, such as her upright walking posture, indicated her place in the human lineage. Her pelvis and knee structure suggested bipedalism, a defining trait of hominins. Although her brain size was still within the range of apes, it was larger than that of earlier ancestors, hinting at cognitive evolution. For two decades, Lucy was the oldest known hominin, shaping the understanding of human evolution.

Subsequent Discoveries and Evolving Perspectives

In recent years, numerous discoveries have emerged that challenge Lucy's status as the sole ancestor of modern humans. Fossils older than Lucy, such as Australopithecus anamensis and Sahelanthropus, have been found, indicating a more complex evolutionary tree. The understanding of the human lineage has shifted from a simple linear model to a more intricate bush-like structure, with multiple branches representing various hominin species coexisting and potentially interbreeding.

Technological Advancements in Fossil Analysis

The methods used to study fossils have evolved significantly. Modern techniques include CT scanning, which allows for detailed analysis of both external and internal features of fossils. Researchers can now extract ancient proteins from bones, enhancing the understanding of species relationships and evolutionary timelines. These advancements have also improved the ability to reconstruct ancient environments, providing context for Lucy's habitat.

Future of Paleoanthropology

The celebration of Lucy's discovery is not only a reflection on the past but also a call to action for the future of paleoanthropology. There is a growing emphasis on involving local researchers from African countries in fossil studies, fostering a collaborative approach to uncovering human history. The complexity of human evolution continues to unfold, with new discoveries expected to reshape the understanding of our ancestry.

Conclusion

Lucy remains a crucial figure in the narrative of human evolution, representing a significant link in the evolutionary chain. As research progresses, the understanding of human ancestry will continue to evolve, highlighting the importance of Lucy and her contemporaries in the broader context of our species' history.

This transcript provides a wealth of information regarding several hominin species and human-like groups, particularly focusing on their time periods and geographic locations. The most notable species mentioned is Australopithecus afarensis, commonly known as 'Lucy', which is a significant find dating back to approximately 3 million years ago. Lucy was discovered in Ethiopia, which highlights the region's importance in the study of human evolution.

Additionally, the transcript references other early hominins such as Orrorin tugenensis, Sahelanthropus tchadensis, and Ardipithecus ramidus. Orrorin tugenensis, while not dated explicitly in the transcript, is implied to be an earlier species. Sahelanthropus, discovered in Chad, is noted for its implications of upright walking, although specific dates are not provided.

Furthermore, the transcript points out that the split between the human lineage and that of chimpanzees likely occurred around 8 million years ago, and researchers have discovered fossils that are older than Lucy, indicating a richer and more complex tree of human evolution than previously understood. These discoveries span across various locations in Africa, including Ethiopia, Kenya, and Tanzania, showcasing the continent's critical role in understanding the origins of humanity.

• [00:25] "the great thing about an anniversary like this is it can help us take tasks of what we learned what we knew before."
• [05:41] "Lucy is still the best candidate right we have a lot more of her and she has features she shares with us but was there another fossil in between another species in between."
• [09:34] "the tree is going to change again so where with new discoveries but by and large AAR ances continues to be the last common ancestor."

The transcript articulates several pivotal claims regarding the process of human evolution, emphasizing both anatomical and behavioral developments that have been essential to the emergence of modern humans. A central figure in this narrative is Lucy, whose discovery drastically shifted the understanding of our evolutionary lineage.

One of the prominent anatomical features highlighted is Lucy's ability to walk upright, which is considered a defining characteristic of the human family. The transcript notes that this is evidenced by her pelvis and knee structure, which indicate bipedalism. In addition to this skeletal evidence, the transcript also mentions that Lucy's brain size was beginning to increase, although it still fell within the range of apes. This increase in brain size is significant as it suggests the early stages of cognitive development.

Moreover, the speaker discusses the evolution of the human family tree, noting that it has transitioned from a simple model, where Lucy was viewed as the sole ancestor, to a more complex model that includes multiple branches and species. This complexity indicates a more intricate evolutionary process with various hominins coexisting and potentially interbreeding. The final assertion involves the idea that the understanding of human evolution is continually evolving as more discoveries are made, suggesting that the tree of life is not static but rather dynamic and subject to change.

• [02:40] "that is a defining feature of being a member of the Human family we know that from her pelvis and her knee."
• [09:20] "the human story is so complicated it's not this simple neat line of one species evolving into another to become us."
• [05:49] "it's not really clear which one gave rise to our genus homo."

The speaker references various types of evidence and data to support claims about human evolution, illustrating a multifaceted approach to understanding our origins. Among the most significant forms of evidence discussed are fossils, which play a crucial role in establishing timelines and anatomical features of early hominins.

1. Fossils: The transcript highlights the discovery of Lucy herself, alongside other specimens, indicating that there are now over 500 specimens of her species, which provide a comprehensive view of anatomical variations. The mention of fossils such as Orrorin tugenensis and Sahelanthropus tchadensis further underscores the importance of fossil evidence in constructing the human lineage.

2. CT Scanning Technology: Advances in technology, such as CT scanning, have allowed researchers to study both the external and internal morphology of fossils, including the shape of the inside of the brain. This technology has revolutionized the way scientists analyze fossil remains, providing deeper insights into cognitive abilities.

3. Protein Analysis: The transcript mentions the extraction of proteins from bones that are as old as 2 million years. This data is critical in determining species relationships and understanding evolutionary pathways.

4. Isotope Analysis: The speaker refers to the study of isotopes from the teeth of both hominins and animals, which helps reconstruct dietary habits and ecological contexts. This analysis aids researchers in building a clearer picture of the environments in which these ancient beings lived.

5. Geological Evidence: Collaboration with geologists to understand ancient geology and volcanics also plays a critical role in dating fossils and reconstructing the habitats of early hominins.

• [07:21] "we now even have started extracting protein from bones that are as old as 2 million years from thousand Africa ancient proteins."
• [08:04] "they also look at the Isotopes from the teeth of the animals and the hominin can tell them what they were eating."
• [07:57] "the technology has changed not only in terms of how we study the bones but also in terms of how we analyze the environment in which these early HS lived."

The transcript provides insights into the uncertainty and evolving nature of scientific understanding regarding human evolution. The speaker highlights that for about 20 years, Lucy was considered the only known member of the human family from approximately 3 million years ago, a period during which significant discoveries were made. However, with the advent of new fossil finds, the understanding of early hominins has shifted considerably. The speaker notes, "Lucy is still the best candidate" for being a direct ancestor, but acknowledges that this status is subject to change as new discoveries are made. This illustrates the fragility of the fossil record and the inherent uncertainties involved in piecing together the timeline of human evolution.

Moreover, the speaker discusses the challenges posed by the gaps in the fossil record. They mention the significant discovery of fossils older than Lucy, which has shifted the conversation about her role in the human lineage. The speaker indicates that while Lucy offers important clues, the existence of other species that lived concurrently complicates the narrative of human ancestry. This suggests that the scientific community remains aware of the limitations of the evidence available and recognizes the potential for new insights to emerge that could redefine established theories.

• [05:40] "Lucy is still the best candidate right we have a lot more of her and she has features she shares with us but was there another fossil in between another species in between."
• [06:00] "The tree is going to change again so where with new discoveries but by and large AAR ancestors continues to be the last common ancestor to those later branches on the tree."

The transcript reveals several scientific debates and competing hypotheses within the field of anthropogeny, particularly concerning the relationships between various hominin species and the complexity of the human family tree. The speaker highlights that Lucy was once viewed as a pivotal figure, the sole ancestor leading to modern humans. However, the emergence of new fossils that are both older than Lucy and contemporaneous with her has generated considerable discussion about the lineage of early hominins. The speaker states that the understanding of human ancestry has evolved from a simple model to a more intricate one, stating that the tree is "beginning to get more filled out".

One of the primary debates arises around the timing of the split between humans and chimpanzees. The speaker mentions that this split is estimated to have occurred around 8 million years ago. Yet, the exact nature of the relationships between these early species remains contested, as researchers continue to discover fossils that challenge previously held views. For instance, the discovery of Ostrapothicus anamensis and Ardipithecus have added layers of complexity to understanding evolutionary pathways.

Furthermore, the ongoing research is not only about the physical evidence but also about understanding behavioral traits and environmental adaptations, which are critical to forming a complete picture of human evolution. The speaker does not rigidly take sides but presents a narrative that underscores the dynamic and often contentious nature of ongoing research in the field.

• [05:56] "Now it's beginning to get more filled out I wouldn't say it's a super bushy tree but there are other fossils hanging on different branches."
• [04:43] "Lucy was not the homon species that came right after the split from the commes over shed with chimpanzees now the split is probably like close to 8 million years ago."

[00:00] she was so primitive in so many ways
[00:03] that scientists felt like they could
[00:05] just reach back and touch the common
[00:07] ancestor we shared with
[00:09] chimpanzees here was a Anonymous human
[00:13] ancestor that had sort of lay in
[00:16] suspended animation for over 3 million
[00:21] years it's been 50 years since Lucy was
[00:24] discovered this is her golden
[00:25] anniversary the great thing about an
[00:27] anniversary like this is it can help us
[00:29] take tasks of what we learned what we
[00:31] knew before Lucy wasn't a lot the first
[00:34] fossil found in Africa researchers
[00:36] didn't believe for a long time that it
[00:37] was a member of the Human family they
[00:39] thought maybe it was an early baboon but
[00:41] it wasn't until the 1950s that
[00:43] researchers began finding fossils in
[00:45] East Africa that showed that there were
[00:47] members of the Human family dating way
[00:49] back to at least 2 million years so the
[00:52] big revolution of Lucy in 1974 when Don
[00:55] Johansson and his student Tom Gray found
[00:57] her was that she was 3 million years old
[01:02] the middle of the day it was hot it was
[01:04] well over
[01:05] 100° I happened to glance over my right
[01:08] shoulder and I saw a little piece of
[01:11] elbow that allows you to flex and extend
[01:15] your arm and as we looked around we saw
[01:18] other pieces we saw a couple of shards
[01:20] of a skull we saw fragments of an armb
[01:23] bone we saw fragments of of a lower jaw
[01:26] and that clinched I knew immediately
[01:29] this was some kind of early
[01:33] hinant one of the members of the
[01:35] Expedition said you really think it's a
[01:37] female I said oh yeah I mean the length
[01:39] of the thigh bone is only about a foot
[01:42] long well maybe it's a child well we
[01:44] looked at the teeth and saw that the
[01:47] third Bowers the wisdom teeth were
[01:48] erupted so this was a mature adult and
[01:53] she said well if you think that why
[01:55] don't we call her Lucy after Lucy in the
[01:57] Sky with Diamonds that was playing and I
[02:00] thought my gosh I've just gotten my PhD
[02:03] I need to find what its scientific name
[02:05] is but it was too late what bothered me
[02:09] was she was found in Ethiopia and she
[02:13] really deserved an Ethiopian name we had
[02:16] members of the ministry of culture at
[02:18] that time come to visit the site and one
[02:21] of them said I think she should be
[02:24] called dinkes and dinkes in amaric means
[02:27] you are wonderful
[02:30] and she certainly
[02:31] is what do we see in her face that we
[02:34] recognize that looks like us what is it
[02:36] in her smile right one she's walking
[02:38] upright okay that is a defining feature
[02:40] of being a member of the Human family we
[02:42] know that from her pelvis and her knee
[02:44] her species brain is beginning to get
[02:46] bigger it's still in the size range of
[02:48] an Apes but it's actually appreciably
[02:51] bigger we thought we were right at the
[02:54] Horizon of when the Human family was
[02:56] born at about 3 million years of course
[02:59] a lot of new discoveries changed that
[03:00] picture for 20 years she was the only
[03:02] only game in town she was it she was the
[03:05] oldest member of the Human family and
[03:07] seen as this whole lineage around at the
[03:10] time as we continued in following years
[03:14] working at hodar and others at other
[03:17] sites there are well over 500 specimens
[03:21] of this species over almost a million
[03:24] years of time this was a highly
[03:26] adaptable species that could live in a
[03:29] multi itude of environments it's known
[03:32] from Ethiopia from Kenya from Tanzania
[03:36] and it has become reference collection
[03:39] whenever new things are found they give
[03:42] us a good sense of how much variation to
[03:45] expect in a single species but that's
[03:47] usually our problem in P anthropology we
[03:49] find one mandible or two teeth and all
[03:53] the subtle differences that we see
[03:55] comparing with others they look like
[03:57] they're taxonomically significant
[04:00] one of the big revolutions since the
[04:01] early '90s is we finally have found
[04:03] fossils that are older than Lucy in
[04:05] Rapid succession we found ostop
[04:08] anamensis that looks a lot like Lucy but
[04:10] that's more
[04:11] primitive then right after that a team
[04:14] found fossils of arpus which is a more
[04:17] primitive
[04:19] homin in the middle of the desert chat a
[04:21] French paleontologist found fossils
[04:23] there something called sahal anthropus
[04:25] Chad Enis and while they didn't find leg
[04:28] bones that proved upright walking they
[04:30] found that the way the skull sat the top
[04:33] the spine suggests upright walking
[04:36] that's when things became like really
[04:38] clear Lucy was not the homon species
[04:41] that came right after the split from the
[04:43] commes over shed with chimpanzees now
[04:45] the split is probably like close to 8
[04:47] million years
[04:49] ago researchers have started finding
[04:51] other Fales that were not only older but
[04:53] also that were alive at the same time as
[04:55] Lucy in 2001 they announced the
[04:59] discovery of a species called
[05:29] that belongs to the brutal the discovery
[05:32] of all these
[05:34] species kind of made Lucy like shy of
[05:37] being the sole ancestor of
[05:40] everything the Human family Tree it used
[05:43] to be a very simple bush with a main
[05:44] trunk leading from Lucy down to our
[05:47] family and others now it's beginning to
[05:49] get more filled out I wouldn't say it's
[05:51] a super bushy tree but there are other
[05:53] fossils hanging on different branches
[05:56] and it's not really clear which one gave
[06:00] rise to our genus homo Lucy is still the
[06:03] best candidate right we have a lot more
[06:05] of her and she has features she shares
[06:07] with us but was there another fossil in
[06:09] between another species in between we
[06:11] now have a partial job which has been
[06:13] dated to 2.8 million years ago and they
[06:16] think this is the earliest homo maybe we
[06:19] will find at some point something that's
[06:21] older than 2.8 million years ago which
[06:23] could represent the first appearance of
[06:26] that genus it puts early homo around at
[06:28] a time when we start to see other
[06:29] species that were alive maybe other
[06:31] species could have been ancestral or in
[06:34] breeding at the edges that's the big
[06:36] mystery right
[06:37] now so the thing that's changed the most
[06:40] in the years that I've been covering
[06:41] human evolution for science is not so
[06:44] much how we actually look for fossils
[06:46] because that's pretty basic I'm sad to
[06:49] say that the only way to find them is to
[06:52] go out there under the African sun and
[06:55] walk and look and look and walk and hope
[06:58] that your eyes fall on something once
[07:01] the fossils are discovered the tools
[07:03] that are put to try to reconstruct not
[07:05] only the fossil but to reconstruct the
[07:08] ancient habitats and dates and geology
[07:11] are tremendous what we had were like
[07:14] calipers measure teeth and measure CR
[07:17] capacity now we have CT scanning
[07:21] technology you could study not only the
[07:23] external morphology but also the
[07:25] internal morphology the shape of the
[07:28] inside of the brain
[07:30] which we couldn't do before we now even
[07:32] have started extracting protein from
[07:35] bones that are as old as 2 million years
[07:37] from thousand Africa ancient proteins
[07:39] are helping us look back in time to to
[07:41] tell if things are from the same species
[07:43] or not are we going to be able to push
[07:45] that technology to actually sample
[07:47] protein from like 3 million year old
[07:49] fossils the technology has changed not
[07:52] only in terms of how we study the bomes
[07:54] but also in terms of how we analyze the
[07:57] environment in which these early HS
[07:58] lived these teams also bring in people
[08:00] in different disciplines that are
[08:02] studying the ancient geology the
[08:04] volcanics for dating and then they also
[08:06] look at the Isotopes from the teeth of
[08:08] the animals and the hominin can tell
[08:10] them what they were eating they can
[08:11] start to build a picture of the world of
[08:14] Lucy's world let's say 3 million years
[08:16] ago when Lucy lived it was not dry it
[08:19] was much higher inm sub altitude and
[08:22] there was a lot of water there were lots
[08:24] of animals that we don't see today in
[08:26] the region they tried to divide their
[08:29] habitat not every animal lives in the
[08:31] same habitat if they did there will be a
[08:33] lot of
[08:34] competition the way fossil hunting has
[08:37] evolved over the years that I've been
[08:38] covering human evolution is also very
[08:40] exciting there are now Africans
[08:43] Ethiopians Kenyans who are leading teams
[08:46] doing research in their country so it's
[08:49] not just as Russia foreigners coming in
[08:51] to treasure hunt and find the best
[08:54] fossils this whole celebration of Lucy
[08:56] 50 is not just about Lucy
[09:00] it's also about thinking about the
[09:02] future her Discovery for example in
[09:04] Ethiopia has built wonderful laboratory
[09:07] we need to do the same in other African
[09:09] countries with a lot of fossil wealth
[09:12] local Scholars get involved in those
[09:14] kinds of research that we do is our
[09:18] advantage the human story is so
[09:20] complicated it's not this simple neat
[09:22] line of one species evolving into
[09:24] another to become us the tree is going
[09:27] to change again so where with new
[09:30] discoveries but by and large AAR ances
[09:34] continues to be the last common ancestor
[09:37] to those later branches on the tree Lucy
[09:40] is one of the most important players and
[09:41] will always be she persists as a really
[09:45] significant member of a really
[09:47] significant species

The Discovery of Dragon Man and Its Implications for Human Evolution

Recent advancements in the study of human evolution have led to the revelation of a new species, dubbed "Dragon Man," which has significant implications for our understanding of human ancestry. This discovery suggests that our relationship with Neanderthals may not be as close as previously thought, and introduces the Denisovans as a crucial player in the narrative of human origins.

The exploration of human ancestry has long been a complex endeavor, with scientists continuously piecing together the intricate family tree of our species. The emergence of the Denisovans, a previously unknown group of ancient humans, has added layers of complexity to this narrative. The Denisovans were first identified through a small finger bone discovered in Denisova Cave, Russia, in 2010. Genetic analysis revealed that this specimen belonged to a distinct species, separate from both Neanderthals and Homo sapiens, marking a groundbreaking moment in paleoanthropology.

As research progressed, scientists uncovered that some modern human populations, particularly Tibetans, carry genetic traits inherited from Denisovans that enable them to thrive in high-altitude environments. This adaptation highlights the Denisovans' unique evolutionary path and their interactions with other human species. However, until recently, the physical appearance of the Denisovans remained a mystery, as only a few fragments of their remains had been found.

The situation changed dramatically with the discovery of a well-preserved skull in Harbin, China, which dates back approximately 146,000 years. This skull, named Dragon Man (Homo Longi), exhibits a robust structure and distinct features that suggest a close relationship with the Denisovans. The skull's discovery has led researchers to hypothesize that it may represent the long-sought "face" of the Denisovans, providing a tangible link to this enigmatic group.

The narrative surrounding Dragon Man is steeped in historical intrigue, as the skull was reportedly hidden during the Japanese occupation of China in World War II. After lying undisturbed for decades, it was rediscovered and eventually analyzed by scientists, who confirmed its significance as a new species. The skull's features, including a pronounced brow ridge and a modernized brain structure, suggest a complex evolutionary history that intertwines with both Neanderthals and Homo sapiens.

Further analysis of the skull and additional fossils from China, such as the Yang Xian 2 skull, has prompted a reevaluation of the human family tree. The Yang Xian 2 fossil, which is around one million years old, challenges previous assumptions about the timeline of human evolution. It suggests that the divergence between Denisovans, Neanderthals, and Homo sapiens may have occurred much earlier than previously believed, potentially over one million years ago.

This new understanding raises questions about the relationships between these species. Traditionally, Neanderthals and Homo sapiens were considered sister species, but emerging evidence suggests that Denisovans may actually be our closest relatives. This shift in perspective is controversial and has sparked debates within the scientific community regarding the accuracy of genetic and morphological analyses.

As researchers continue to explore these findings, they are also investigating the implications of the Denisovans' adaptations to various environments. Evidence indicates that some Denisovans were well-suited to cold climates, while others thrived in warmer regions, suggesting a diverse and adaptable species. This adaptability contrasts with Neanderthals, who seem to have struggled in extreme conditions.

Additionally, the archaeological record of the Denisovans is limited compared to that of Neanderthals, making it challenging to fully understand their culture and lifestyle. The Denisova Cave has yielded some artifacts, but it is essential to consider that it was also inhabited by Neanderthals and Homo sapiens, complicating the attribution of cultural practices.

In contrast, the Bashia Cast Cave on the Tibetan Plateau appears to have been exclusively occupied by Denisovans, providing a unique opportunity to study their behavior and adaptations. Excavations at this site have revealed evidence of fire use and hunting practices, indicating that Denisovans were capable of surviving in harsh environments, even at high altitudes.

The implications of these discoveries extend beyond the Denisovans themselves. They challenge the long-held belief that modern humans originated solely in Africa, suggesting instead that our common ancestors may have emerged in Asia. This theory, while controversial, underscores the need for further research and fossil discoveries to clarify the complex web of human evolution.

As the field of paleoanthropology continues to evolve, the discoveries surrounding Dragon Man and the Denisovans serve as a reminder of the dynamic nature of scientific inquiry. Each new fossil or piece of evidence has the potential to reshape our understanding of human history, prompting us to reconsider our place within the broader narrative of life on Earth. The ongoing exploration of our origins is not just an academic pursuit; it is a quest to understand what it means to be human in a world filled with mysteries yet to be unraveled.

The transcript outlines various hominin species and human-like groups, providing insights into their chronological existence and geographical origins. The following species are mentioned:

• Neanderthals: Closely related to modern humans, Neanderthals are discussed in relation to their evolutionary significance. They are inferred to have existed around 500,000 years ago and are primarily associated with Eurasian terrains.
• Denisovans: This group was identified through DNA analysis from a finger bone found in Denisova Cave, Russia. The species is suggested to have been contemporary with Neanderthals and possibly modern humans, living roughly 300,000 to 146,000 years ago. Their presence has also been linked to Tibet, where adaptations for high-altitude living have been observed.
• Homo Longi (Dragon Man): Discovered in Harbin, China, this species is described as a new addition to the human family tree, potentially dating back 146,000 years. The skull's robust features suggest it may be related to the Denisovans.
• Homo Erectus: The transcript mentions a skull, Yang Xian 2, dated to about 1 million years old, which challenges the understanding of human evolution timelines. This species is generally associated with early human development and is believed to have existed in Asia and Africa.
• Australopithecus: While not specifically mentioned in the transcript, it is generally acknowledged as an early hominin significant to human evolution. The transcript focuses more on later species.

These species illustrate the complex tapestry of human evolution, suggesting that multiple human-like groups coexisted in various regions, particularly across Asia and Europe.

• [01:02] "...by the time our species appears around 300,000 years ago, it shared the world with as many as six, perhaps more other human species."
• [04:18] "...they realized it was a new species and they called it Homo Longi or Dragon Man."
• [08:40] "...ancestor X is the name sometimes given to the common ancestor of ourselves, the Denisovans, and the Neanderthals."

The transcript presents several central claims regarding the process of human evolution, emphasizing the complexity and diversity of our ancestral lineage. Key assertions include:

• Human Evolution is Complex: The transcript highlights that the human family tree is not linear but rather a tangled web of various species coexisting at different times. The discovery of multiple hominin species has reshaped our understanding of human origins.
• Discovery of New Species: The identification of the Denisovans and Homo Longi (Dragon Man) suggests that the human lineage may be more diverse than previously thought. The robust skull of Dragon Man is proposed as a potential face of the Denisovans, indicating a close relationship between these groups.
• Geographical Context: The narrative suggests a shift in thinking about where modern humans and their relatives originated, positing that significant developments may have occurred in Asia rather than solely in Africa. The mention of ancient human activities in high-altitude environments suggests adaptive behaviors that were crucial for survival in diverse climates.
• Revisiting Relationships Among Species: The transcript discusses the possibility that Neanderthals may not be the closest relatives to modern humans, as new analyses suggest Denisovans could occupy that position. This challenges long-held beliefs about human ancestry.

Overall, these claims underscore a dynamic and ongoing exploration of human evolution, where new findings continuously prompt a reevaluation of what it means to be human.

• [01:36] "...they realized it was not a Neanderthal and it was not a Homo sapien. However, it was a human."
• [09:16] "...the common ancestor might even have lived somewhere like Western Asia."
• [12:07] "...if it's a species that was hanging out at really high altitude all the way over in the east in Asia, does kind of paint a slightly different picture."

The speaker references various types of evidence to support claims regarding human evolution, emphasizing the significance of fossils, genetics, and archaeological findings. The key types of data mentioned include:

• Fossils: The discovery of the Dragon Man skull in Harbin, China, is a pivotal finding that provides new insights into human evolution. This fossil, along with others like Yang Xian 2, is used to reconstruct the human family tree and re-evaluate relationships among species.
• Genetic Data: DNA analysis plays a crucial role in the identification of the Denisovans. The sequencing of their genome has revealed adaptations, such as those found in modern Tibetans, who possess DNA from Denisovans that allows them to thrive in high-altitude environments. The analysis also raises questions about the divergence timelines between various hominin groups.
• Comparative Studies: The transcript mentions comparative anatomical analyses that challenge previous understandings of relationships among species. For instance, the potential re-evaluation of Neanderthals as not being the closest relatives to modern humans is partly based on anatomical comparisons.
• Archaeological Finds: The findings at Denisova Cave, including stone tools and jewelry, illustrate the cultural complexity of Denisovans. In contrast, the Bashia Cast Cave in Tibet is significant because it suggests exclusive habitation by Denisovans, providing insights into their lifestyle, including hunting practices and environmental adaptation.

In summary, the integration of fossil evidence, genetic data, and archaeological discoveries is fundamental to understanding the intricate narrative of human evolution.

• [00:10] "...it has kind of opened up a can of worms for us because potentially it has suggested that we are no longer as closely related to the Neanderthals as we once thought."
• [12:38] "...we know from DNA evidence that at least some Neanderthals were well adapted genetically to high altitude."
• [10:21] "...there's some ones from Africa that are about a million years old. It will be important to put them in too."

The transcript discusses the reliability and uncertainty of the data surrounding human origins and anthropogeny, emphasizing the complexities and ongoing debates within the scientific community. The speaker highlights that the fossil record is sparse and that many significant discoveries, such as the Denisovans and the newly identified Homo Longi (Dragon Man), challenge existing theories about human evolution. The scientist expresses the notion that our understanding is continually evolving, stating, "[18:18] ...we just don't know if what we have in research labs and museums is accurate and paints a proper picture of our story or if it really is just giving us snapshots." This reflects a broader concern about the fragility of evidence in paleoanthropology.

Furthermore, the speaker mentions the necessity for further discoveries to support or contest current findings. For instance, they note that recent fossil discoveries, such as those in Morocco, could potentially support the claim that humans may be older than previously believed. Additionally, the speaker remarks, "[10:12] ...the coming years are going to be crucial in seeing what evidence backs up this 1 million-year claim..." This illustrates a recognition of the provisional nature of scientific conclusions in the face of new evidence and the scarcity of data that can lead to significant shifts in understanding human ancestry.

• [18:18] "We have so few fossils, so few data points that we just don't know if what we have in research labs and museums is accurate..."
• [10:12] "The coming years are going to be crucial in seeing what evidence backs up this 1 million-year claim..."

The transcript reveals several scientific debates and competing hypotheses regarding human evolution, particularly the relationships among various species, including Homo sapiens, Neanderthals, and Denisovans. One significant point of contention is the ancestor-descendant relationships among these groups. The speaker mentions that previous analyses suggested Neanderthals and Homo sapiens were sister species; however, new findings, particularly those related to the Yungshan 2 fossil, challenge this perspective. The transcript states, "[07:07] ...this group could be more closely related to Homo sapiens which is a conflict then potentially with much of the genetic data," indicating a division in the scientific community regarding the lineage and relationships of these early humans.

Another area of debate is the geographical origins of these species. The speaker introduces the controversial claim that our common ancestors may not have originated in Africa, as traditionally thought, but perhaps in Asia instead. This assertion is based on the age and significance of the Yungshan 2 fossil, which could push back the timeline of human ancestry and suggests, "[11:11] ...that our common ancestor might even have lived somewhere like Western Asia." The mention of differing perspectives, such as the divergence dates between species, indicates that the scientific community is grappling with conflicting evidence and interpretations.

• [07:07] "This group could be more closely related to Homo sapiens which is a conflict then potentially with much of the genetic data."
• [11:11] "...the common ancestor might even have lived somewhere like Western Asia."

[00:00] One of the biggest mysteries in human
[00:01] evolution has finally just been solved.
[00:04] But in doing so, it has kind of opened
[00:06] up a can of worms for us because
[00:09] potentially it has suggested that we are
[00:12] no longer as closely related to the
[00:14] Neanderthalss as we once thought and
[00:16] that there is another player in the
[00:18] room. I'm working with Chinese
[00:20] colleagues on studying really
[00:22] interesting fossils from China which I
[00:23] think will have a big impact on this
[00:25] story of our origins. The origins of the
[00:27] Neandals and the origins of the Denisven
[00:30] >> the question was who were the mysterious
[00:33] Denisans? Where did we come from? It's
[00:36] one of the most fundamental questions we
[00:38] ask ourselves. Every year scientists get
[00:40] closer to discovering the answer. In
[00:43] fact, one of the great discoveries of
[00:44] the 21st century is that the human
[00:46] family tree is far more tangled and
[00:48] diverse, far more complicated, perhaps
[00:51] more interesting than we could have
[00:52] imagined, with two or more human species
[00:54] often living at the same time, even in
[00:57] the same place. And by the time our
[00:59] species appears around 300,000 years
[01:02] ago, it shared the world with as many as
[01:04] six, perhaps more other human species.
[01:08] Now, thanks to a 146,000-year-old
[01:11] skull unearthed in Harbin, China, what
[01:13] we think we know about who we are, where
[01:15] we come from, and who we call our
[01:17] closest relative may just be changing.
[01:20] Meet Dragon Man. Yes, I did say Dragon
[01:23] Man.
[01:27] In 2010, a tiny finger bone was
[01:30] discovered in a cave called Denisva Cave
[01:32] in Russia. But upon extracting its DNA,
[01:34] they realized it was not an Neanderthal.
[01:37] and it was not a homo sapien. However,
[01:40] it was a human. And so they realized
[01:42] that they had accidentally stumbled upon
[01:44] a whole new species of human. This had
[01:47] never happened before. We were never in
[01:49] a situation where a new human had been
[01:52] discovered through DNA. It had always
[01:54] been through fossils. And so we were in
[01:56] this very complicated situation where we
[01:59] had the DNA of a species, but we had no
[02:02] idea what it looked like. In fact, they
[02:05] managed to sequence the whole genome of
[02:08] this species which they called the
[02:10] denisven. And when they sequenced that
[02:12] genome, they found all kinds of
[02:15] additional mysteries hidden within it.
[02:16] Like for example, Tibetans who are able
[02:18] to exist at very high altitude.
[02:21] >> These people, some of them at least were
[02:23] adapted to very cold conditions and
[02:25] interestingly some populations in Tibet
[02:27] today have DNA from denissance that
[02:29] helps them live at high altitude in low
[02:31] oxygen conditions. But still there was
[02:34] no face to the denisens. In fact, there
[02:35] were really no fossils beyond that one
[02:37] tiny fingerbone and a few teeth. And so
[02:40] we started saying that perhaps this is
[02:42] the holy grail of paleo anthropology. We
[02:44] knew that these denisans were very
[02:47] closely related to Neanderthalss.
[02:50] But beyond that, we were kind of stumped
[02:52] and then a tiny bit of jawbone was
[02:56] analyzed. Now this jawbone was found in
[02:59] Tibet. And upon DNA analysis, they
[03:01] realized that it was Denisven. Great. We
[03:05] finally had a bit more of a fossil, but
[03:07] it was just a tiny bit of jawbone. And
[03:09] lo and behold, finally, this summer, the
[03:13] whole mystery blew up. And this is how
[03:15] it went down.
[03:19] Back in World War II, the story goes
[03:22] that a man in China, while China was
[03:24] Japanese occupied, found a fascinating
[03:27] skull. Now if you look at this skull you
[03:29] can see it is quite large. It is more
[03:31] robust than you would even expect from a
[03:33] Neanderthal.
[03:34] >> The workers who found it in the river
[03:35] grabbles at Harbin decided to keep it
[03:38] away from the Japanese and they actually
[03:40] one of them took it home and wrapped it
[03:42] up and put it down a well a dissued
[03:44] well. And it lay there for the next 80
[03:47] years or so until that person on their
[03:49] deathbed told their relatives to go and
[03:50] look down the well. And sure enough they
[03:52] found this beautifully preserved fossil
[03:54] down there. And then fast forward
[03:55] another few years and it ends up with us
[03:57] studying it and publishing it in 2021.
[04:00] We're not sure if that story is true. So
[04:02] there is work going on in Harbin to try
[04:05] and pin down more accurately uh the
[04:08] history, the early history of this
[04:09] fossil.
[04:09] >> Now when the scientists looked at this
[04:11] fossil, they realized that it wasn't an
[04:14] old fossil that they already knew. They
[04:16] realized it was a new species and they
[04:18] called it Homo Longi or Dragon Man. So,
[04:22] brilliant name, by the way, to give a
[04:24] species. And it was it was really
[04:26] fascinating. It was great to have a new
[04:28] species of human to add to the family
[04:30] tree. But here's where it gets
[04:32] interesting. They kept looking at this
[04:33] skull thinking, "We think we have this
[04:36] suspicion that Homo Longi or Dragon Man
[04:40] may just be the face of the Dissipants,
[04:42] that it is finally the holy grail, that
[04:45] we have finally found it. But to do
[04:47] that, they did need to extract DNA. And
[04:49] in the summer of 2025,
[04:52] they managed to confirm that the DNA of
[04:55] Homolongi, the DNA of Dragon Man matches
[04:59] the DNA of the Denisans. And so finally,
[05:03] we were able to look into the face of
[05:05] the Denisans.
[05:07] >> So I mentioned the massive size of this,
[05:08] of course, it's got the huge brow ridge,
[05:10] which many of these have got and very
[05:12] big brain in there, a completely
[05:13] modernized brain. um and a mixture of
[05:15] features which for this is long and low
[05:18] the brain case which is like Neanderles
[05:20] but when we look at the face it's much
[05:23] more like the face of homo sapiens it's
[05:25] flat across and it's tucked under the
[05:27] brain case so an interesting mixture of
[05:29] features there so speculation was that
[05:31] this could be a denisant um and our
[05:34] ongoing analysis suggests that it is and
[05:36] that most of those other Chinese fossils
[05:38] belong in the denisan group as well
[05:40] >> but the scientists weren't finished yet
[05:42] because a few months ago they looked at
[05:44] Another ancient skull found in China
[05:46] called Yang Xian 2. This one was about 1
[05:49] million years old which is about to
[05:51] become very significant. However, this
[05:53] skull was very badly squashed. But
[05:56] scientists reconstructed it and in doing
[05:58] so and in comparing it to Dragon Man and
[06:02] other early human fossils, they started
[06:04] drawing a different family tree
[06:10] >> because if I can come on to this Yungjan
[06:12] fossil. So this one um is from a site
[06:16] where there there are three crania and
[06:17] this is the one that we managed to
[06:18] reconstruct. So my Chinese colleagues
[06:20] use highquality CT scans. The original
[06:23] fossil is crushed down and distorted but
[06:25] they basically use CT scanning to take
[06:28] it apart and put it back together again,
[06:29] make it symmetrical and we end up with
[06:31] this reconstructed fossil and it's a
[06:33] million years old that the fossils from
[06:35] this site are a million years old give
[06:37] or take 100,000 years and that would
[06:40] suggest that they should be Homo
[06:41] erectus. So the default is that humans
[06:43] large brain humans a million years ago
[06:45] will be homo erectus but this isn't an
[06:47] erectus skull and our analysis certainly
[06:49] confirmed that. So the DNA evidence
[06:51] would suggest that denisphans are more
[06:53] closely related to neanderals than they
[06:56] are to us homo sapiens whereas our
[06:59] analyses of harbin our analyses of the
[07:01] Chinese material suggests that actually
[07:02] this group could be more closely related
[07:04] to homo sapiens which is a conflict then
[07:07] potentially with much of the genetic
[07:08] data. See, around 500,000 years ago, we
[07:11] think broadly many species fell into
[07:14] three groupings. Homo sapiens, modern
[07:17] humans, Neanderthalss, and the denisans.
[07:20] And we had thought that the
[07:22] Neanderthalss and homo sapiens were the
[07:24] most closely related, that we were
[07:26] sister species. Now, this is based on
[07:28] DNA analysis and anatomical analysis.
[07:31] But with the addition of the young Shian
[07:35] 2 fossil, this family tree was starting
[07:38] to look really different because they
[07:39] suggested that actually homo sapiens and
[07:43] Neanderthalss are not the most closely
[07:45] related. That actually our closest
[07:48] relative were the Denisans. If that is
[07:51] true, that means that the Neanderthalss
[07:53] are more distantly related than we
[07:55] realized. Now, it's incredibly
[07:57] controversial because the DNA analysis
[07:59] doesn't necessarily back that up, but it
[08:03] is incredible to think about.
[08:04] >> Genetic data often suggests there's a
[08:06] divergence between us and the antiles
[08:08] and possibly 600,000 years ago. Our
[08:11] analysis suggested that divergence
[08:12] probably goes back at least a million
[08:14] years. So, a much deeper divergence and
[08:16] then earlier diversification of those
[08:19] lineages. So, we've got potential
[08:21] conflicts between our morphological
[08:23] analyses and the genetic data. But it
[08:25] has to be said that even for the genetic
[08:26] data, there are other geneticists who
[08:28] have deeper divergences and different
[08:30] relationships between the groups.
[08:32] >> Ancestor X is the name sometimes given
[08:34] to the common ancestor of ourselves, the
[08:38] Denisven, and the Neanderthals. Put
[08:40] another way, it means that ancestor X
[08:44] eventually gave rise to the
[08:45] Neanderthals, to ourselves, and to the
[08:49] Denisans. See, because Yang Xian 2 is 1
[08:53] million years old, it means that our
[08:55] common ancestor, Homo sapien, and the
[08:58] Denisan common ancestor must be over 1
[09:01] million years old. And logically,
[09:03] therefore, it means that we must be
[09:06] older than the 300,000 years that we
[09:09] thought we were. We must also be around
[09:11] 1 million years or older because our
[09:14] sister species is. You can imagine that
[09:16] is kind of a bombshell. It's still very
[09:20] controversial and we still need a lot
[09:22] more data
[09:23] >> and let's see where it goes. And we've
[09:25] got more to do because there are many
[09:27] traits that we haven't managed to put
[09:28] into the analysis yet. For example, the
[09:31] earbones, they're very important in
[09:33] terms of taxonomy. So, Neanderl
[09:35] earbones, tiny little bones inside,
[09:37] buried deep in the temporal bone.
[09:38] They're distinct in shape from our own.
[09:40] So, we want to analyze the earbones of
[09:42] these fossils and see how they relate.
[09:44] It's important to remember that
[09:45] additional fossil discoveries are really
[09:48] crucial when these kinds of
[09:50] announcements are made because they can
[09:51] either support or not support the
[09:54] findings. In fact, very recently,
[09:56] scientists announced that they had found
[09:58] some human fossils in Morocco that are
[10:00] about 3/4 of a million years old. And
[10:02] the suggestion is that they're very
[10:04] early homo sapien. The coming years are
[10:07] going to be crucial in seeing what
[10:10] evidence backs up this 1 million-year
[10:12] claim and potentially that Moroccan
[10:14] evidence might support it.
[10:16] >> And there are other fossils we haven't
[10:17] managed to put into the analysis yet. So
[10:19] there's some ones from Africa that are
[10:21] about a million years old. It will be
[10:22] important to put them in too. And
[10:24] there's some new material from atapa in
[10:26] Spain, maybe 1.2, to 1.3 million years
[10:29] old, which could be a late form of Homo
[10:32] erectus, but it might even relate to
[10:34] some of these early divergences when we
[10:36] when we get more data on it.
[10:37] >> The scientists behind the young Xiang
[10:40] research aren't just wanting to push
[10:42] back the date of our origins. They're
[10:45] also suggesting that perhaps
[10:48] we and the Denisvens, our common
[10:51] ancestor, didn't actually originate in
[10:53] Africa, but originated in Asia. And they
[10:56] claim this because if that young Shiang
[10:59] fossil is a million years old, it is
[11:01] technically the oldest fossil we have of
[11:03] a denisan or a homo sapiion and
[11:06] therefore it places the common ancestor
[11:08] potentially not in Africa but in Asia.
[11:11] But as you can imagine that is an
[11:13] incredibly controversial claim.
[11:16] >> So the picture seems to be that uh you
[11:19] know these groups evolved largely
[11:21] separately. Neandertos in the west of
[11:23] Eurasia, Homongi over in the east of
[11:25] Eurasia, Homongi Dunisants and us in
[11:28] Africa. Um the common ancestor
[11:30] interestingly may not have started off
[11:32] in Africa. That's one of the interesting
[11:33] things is that our analyses suggests the
[11:35] common ancestor might even have lived
[11:37] somewhere like Western Asia.
[11:39] >> It upends so much theory and research
[11:42] that's already out there. It isn't just
[11:44] that it potentially changes all those
[11:46] textbooks. It also kind of changes the
[11:49] image we have of us in our head. So
[11:52] often we imagined that that species that
[11:55] hung out in quite cold climates or um
[11:58] more temperate climates was our closest
[12:00] relative, that kind of European West
[12:03] Asian species. But actually, if it's a
[12:05] species that was hanging out at really
[12:07] high altitude all the way over in the
[12:10] east in Asia, does kind of paint a
[12:13] slightly different picture. There are
[12:14] even reconstructions of the range of
[12:16] these populations and some of those
[12:18] which are based on climate modeling
[12:20] suggest that denisphans could have
[12:21] actually ranged even more widely to the
[12:23] west even right across Asia even towards
[12:27] eastern Europe it's possible that
[12:29] denisphans at times extended westwards a
[12:31] lot further than we know them
[12:32] >> what would the denisans being such an
[12:34] explosive species potentially you would
[12:37] think we would know a lot more about
[12:38] them but actually we don't know that
[12:41] much about the denisipans it's not like
[12:43] the Neanderthalss where we have lots and
[12:45] lots of artifacts. We are really
[12:48] clutching at straws here. But here's
[12:50] what we do know.
[12:54] So far, scientists have only found two
[12:57] sites that are Denisven. One is the
[13:00] Denisa cave itself in Russia where
[13:02] archaeologists have found hundreds of
[13:04] stone tools as well as some spectacular
[13:06] jewelry. We're talking here about
[13:08] headbands carefully carved out of woolly
[13:11] mammoth ivory and a bracelet of green
[13:13] rock that is so finely polished. It
[13:15] would look quite spectacular today in a
[13:17] modern jeweler store. However, and this
[13:20] is the really really important bit,
[13:22] Denisa cave did not just belong to
[13:26] Denisven. See, it was dwelled in by the
[13:28] Denisans, yes, but also by Neanderthalss
[13:31] and by Homo sapiens. Some have suggested
[13:33] that the Denisvens are behind that
[13:35] jewelry. Although most seem to think
[13:37] that actually it belongs to homo
[13:39] sapiens. This is why Bashia cast cave on
[13:42] the Tibetan plateau is so important
[13:44] because as far as archaeologists can
[13:46] tell Denisven were the only humans who
[13:48] lived there. So any artifacts they find
[13:51] in the cave must have been used and left
[13:53] by Denisven. Excavations there have
[13:56] barely begun. But already they suggest
[13:58] that Denisven built fires in the cave as
[14:01] well as venturing out on the Tibetan
[14:03] plateau to hunt an amazing range of
[14:06] animals including snow leopards, birds,
[14:08] and rodents. From cut marks left on some
[14:11] of these animal bones, it also looks
[14:14] like the denisven stripped the animals
[14:16] of their skins, perhaps turning them
[14:19] into clothes. Now, this might seem to be
[14:21] exactly the way ancient humans from the
[14:23] Stone Age should behave, living in caves
[14:26] and hunting wild animals for their meat
[14:28] and fur, but there's something about
[14:30] Bashia Cast Cave that doesn't fit with
[14:32] our expectations of ancient human
[14:35] behavior, and it's the location. Bashia
[14:38] Cast lies about 3,200 m above sea level.
[14:42] Life at that altitude can be tough. Some
[14:45] of the archaeologists who have visited
[14:47] the cave have complained that the thin
[14:49] air gives them headaches. But the
[14:51] Denisans, on the other hand, seem to
[14:53] have thrived there, maybe even at higher
[14:56] altitudes because archaeologists
[14:58] recently found signs of ancient Denisven
[15:00] activity on the Tibetan plateau at a
[15:03] site 3,700
[15:05] m above sea level. Why would one group
[15:08] of Denisans have decided to move into
[15:10] such a challenging environment? They
[15:13] probably didn't have to. There weren't
[15:15] that many humans on Earth at that time.
[15:17] So, it's unlikely that anyone was
[15:19] forcing them to climb up into the
[15:21] Tibetan plateau just to find some space
[15:23] to call home. Some of them at least were
[15:26] adapted to very cold conditions. Harbin
[15:28] today is one has some of the coldest
[15:30] winters in the whole of China. Average
[15:31] about -15 or -6 in the winter. So, these
[15:34] people were coping with extreme cold
[15:37] more so than the adults. And yet the DNA
[15:40] data in humans today of Denisven
[15:43] suggests that some of the interbreeding
[15:45] with denisphants happened much further
[15:47] south possibly in island Southeast Asia
[15:49] places like Somatra, Borneo, Sulowi. So
[15:52] Denisans may have been living down there
[15:54] as well. And of course that's a very
[15:55] different region. Uh we've got you know
[15:58] subtropical and tropical conditions. So
[15:59] the denisphins look like a much more
[16:01] varied group than Neandertos both
[16:03] genetically in terms of the different
[16:05] groups that diverged early and also in
[16:07] terms of their adaptive capabilities.
[16:09] Neandertos ranged a long way east and
[16:11] west but when it got really cold they
[16:13] disappeared. These people homongi seemed
[16:16] to have coped with some extremely cold
[16:18] conditions but also down south with much
[16:20] warmer conditions. Now, we know from DNA
[16:22] evidence that at least some
[16:23] Neanderthalss were well adapted
[16:26] genetically to high altitude, which
[16:28] means that like the Neanderthalss, like
[16:30] ourselves, they were incredibly well
[16:32] adapted to their environment. However
[16:35] unusual that environment might seem to
[16:38] us,
[16:41] New Scientist has been following
[16:43] questions like this for decades. Since
[16:46] 1956, their journalists and editors have
[16:49] worked with researchers across
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[17:37] And if you're drawn to the kind of
[17:38] scientific discoveries that spark real
[17:40] debate and controversy, then you're
[17:42] going to love this next part. 2025 was
[17:45] for me a absolutely fascinating year
[17:49] because of these Denise discoveries.
[17:51] See, not only were we finally able to
[17:53] put a face on the Denisven, but it did
[17:55] become the gift that kept on giving and
[17:57] it made us question and still question
[18:00] who we are and where we come from. And
[18:02] that is the reality of paleo
[18:04] anthropology. We kind of think we have a
[18:07] picture of the family tree of where we
[18:09] fit into it and then a fossil is
[18:11] discovered that just changes the whole
[18:14] picture. The reality is that we have so
[18:16] few fossils, so few data points that we
[18:18] just don't know if what we have in
[18:21] research labs and museums is accurate
[18:24] and paints a proper picture of our story
[18:28] or if it really is just giving us
[18:30] snapshots. And there is a lot left to be
[18:34] discovered.
[18:34] >> And of course, all of this is is really
[18:36] building up to the the really big
[18:38] question that we still don't have an
[18:40] answer to. Why are we the only last
[18:42] species? Why why are we the only
[18:44] survivors of all these experiments in
[18:46] how to be human? Um, you know, as I say,
[18:48] 100,000 years ago, there probably five
[18:50] or six different kinds of human around
[18:51] on the planet. Now there's only us. So
[18:54] why is that? Was there something special
[18:55] about us? Did we get lucky? What was the
[18:58] fundamental reason for our success? if
[19:00] you can call call it that. When you look
[19:02] at what we're doing to the planet now,
[19:03] >> it is amazing how much mystery each of
[19:06] those skulls can hold, containing entire
[19:08] lives stories and questions about where
[19:11] we come from and who we're related to.
[19:13] And remember, it all started with a tiny
[19:17] finger bone. If you want to keep digging
[19:20] into what other ancient faces can tell
[19:22] us about our origins, check out our
[19:24] conversation with paleo anthropologist
[19:26] Chris Stringer. Until next time, stay
[19:28] curious.

Human evolution is often perceived as a simple, linear progression, culminating in the emergence of Homo sapiens as the sole surviving species. However, this narrative is misleading. In reality, human evolution has been a complex process characterized by diversification and coexistence among multiple human species. For most of our history, Homo sapiens shared the planet with various other human species, each with unique traits and abilities. This presentation aims to explore six ancient human species that once inhabited the Earth alongside our ancestors, revealing a more intricate and nuanced family tree than commonly understood.

The notion of a straightforward evolutionary path is challenged by the fact that for tens of thousands of years, multiple human species coexisted. Some of these species were physically stronger, others were shorter, and some displayed remarkable intelligence. The fossil and genetic records indicate that human evolution is not a linear story but rather a branching tree of diverse species. This complexity is underscored by the fact that many traits we consider uniquely human may have originated from these earlier species.

Among the ancient human species discussed are the Neanderthals, Homo floresiensis (often referred to as "the Hobbit"), and the Denisovans. Each of these species contributed to the rich tapestry of human evolution, and many modern humans carry genetic legacies from these ancient relatives. The presentation highlights the surprising similarities and differences between these species and Homo sapiens, emphasizing that many characteristics we attribute to modern humans were shared with our ancient cousins.

Neanderthals, or Homo neanderthalensis, are perhaps the most well-known of these ancient humans. They thrived in Europe and parts of Asia, with a robust physique adapted for Ice Age hunting. Neanderthals stood about 5.5 feet tall and possessed a strong build, with dense bones and thick muscle mass. Contrary to the stereotype of Neanderthals as brutish cavemen, they exhibited complex behaviors, including the use of fire, tool-making, and possibly even artistic expression. Their brain size was comparable to that of modern humans, suggesting they were capable of sophisticated thought and social interaction.

Despite their similarities, Neanderthals eventually went extinct around 40,000 years ago, shortly after the arrival of Homo sapiens in Europe. The reasons for their extinction remain a topic of debate among scientists. Some hypotheses suggest competition for resources, climate change, or even disease as potential factors. However, it is crucial to note that all non-African modern humans carry a small percentage of Neanderthal DNA, a testament to the interbreeding that occurred between the two species.

Another fascinating species is Homo floresiensis, discovered on the island of Flores in Indonesia. This species is notable for its diminutive stature, with adults averaging about 3.5 feet in height. The small size is attributed to a phenomenon known as island dwarfism, where species evolve smaller body sizes in response to limited resources on islands. Despite their small brains, comparable in size to those of chimpanzees, Homo floresiensis demonstrated the ability to create and use stone tools, challenging assumptions about the relationship between brain size and intelligence.

The extinction of Homo floresiensis around 50,000 years ago raises questions about their lifestyle and survival strategies. They likely scavenged for food, possibly relying on the remains of larger animals, such as the dwarf elephants that once roamed Flores. The disappearance of these large prey animals, coupled with environmental changes, may have contributed to their extinction. The unique adaptations of Homo floresiensis highlight the diverse evolutionary experiments that took place in human history.

The Denisovans, a lesser-known group, were identified primarily through genetic analysis rather than fossil evidence. The first Denisovan remains were discovered in a cave in Siberia, and subsequent DNA analysis revealed that they interbred with both Neanderthals and modern humans. This genetic legacy persists in many contemporary populations, particularly among Tibetans, who possess adaptations for high-altitude living linked to Denisovan ancestry. The Denisovans' ability to thrive in various environments across Asia underscores the adaptability and resilience of ancient human species.

Homo heidelbergensis, another significant ancestor, is believed to have lived in Europe, Africa, and possibly Asia. This species exhibited a mix of primitive and advanced features, with a larger brain than Homo erectus and evidence of complex behaviors, including hunting and possibly the construction of shelters. Their existence around 700,000 years ago marks a crucial point in human evolution, as they are thought to be a common ancestor of both Neanderthals and modern humans.

Homo naledi, discovered in South Africa, presents an intriguing case in the study of human evolution. This species, with a small brain size, exhibits a combination of primitive and modern traits. The discovery of intentional burial practices among Homo naledi raises questions about their cognitive abilities and social behaviors. The implications of these findings challenge traditional notions of what it means to be human and suggest that complex behaviors may not be exclusive to species with larger brains.

As we explore these ancient species, it becomes evident that human evolution is characterized by a rich diversity of forms and behaviors. The interactions between these species, including competition, interbreeding, and shared environments, played a significant role in shaping the trajectory of human evolution. The genetic evidence of interbreeding between Homo sapiens, Neanderthals, and Denisovans illustrates the interconnectedness of our species and highlights the complexity of our evolutionary history.

In conclusion, the story of human evolution is far from linear. The coexistence of multiple human species, each with unique adaptations and behaviors, paints a more intricate picture of our ancestry. The discoveries of ancient human fossils and genetic analysis continue to reshape our understanding of who we are and where we come from. As research advances, we can expect to uncover even more about our ancient relatives and the factors that contributed to the survival of Homo sapiens as the last remaining human species.

Ultimately, the exploration of our ancient family tree reveals that we are not alone in our evolutionary journey. The legacies of Neanderthals, Homo floresiensis, Denisovans, and other ancient species live on in our DNA, reminding us of the shared history that connects us to the diverse tapestry of humanity. As we continue to investigate the past, we may find that the answers to our questions about human evolution are still waiting to be discovered.

The transcript provides insights into several hominin species, each with distinct characteristics, time periods, and geographical locations. Below is a detailed list of these species:

• Neanderthals (Homo Neanderthalensis): This species emerged around 500,000 years ago and was primarily located in Europe and Asia. They were known for their robust build and were skilled Ice Age hunters.
• Homo erectus: This species is noted as the longest-surviving ancestor, existing for approximately 2 million years until around 100,000 years ago, with evidence of their presence in Africa and Java. Homo erectus is credited with significant evolutionary advancements, including the control of fire and the development of early stone tools.
• Homo floresiensis (the Hobbit): This species lived around 80,000 years ago on Flores Island in Indonesia. They were notably small, standing about 3.5 feet tall and exhibiting unique traits that challenge conventional views of human evolution.
• Denisovans: While specific dates are not provided, they are referenced as a group that coexisted with Neanderthals and modern humans across various locations, including eastern Asia and the Tibetan plateau.
• Homo heidelbergensis: This species is believed to have existed around 700,000 years ago and is noted for having larger brain sizes compared to earlier ancestors, with fossils found in Europe and Africa.
• Homo naledi: This species, which lived between 2 to 300,000 years ago, was discovered in a cave near Johannesburg, South Africa. It has been associated with potentially complex behaviors.

• [05:02] "Neanderthals, of course, are really the best known ancient humans... They were strong. They were incredible Ice Age hunters."
• [11:00] "Homo erectus... survived as late as 100,000 years ago on the island of Java."
• [20:55] "Homo floresiensis is a remarkable species... Some of them were barely more than a meter tall as adults."

The transcript outlines several central claims regarding the complex and non-linear process of human evolution, emphasizing diversification rather than a straightforward lineage. The following key assertions are made:

• Human Evolution is Non-linear: The speaker highlights that human evolution is not a linear progression from one species to another; instead, it involves multiple hominin species coexisting and interacting over time.
• Diversity of Hominin Species: The transcript mentions the existence of various ancient human species, such as Neanderthals, Homo erectus, and Homo floresiensis, indicating a rich tapestry of human ancestry that includes both similarities and differences.
• Behavioral and Anatomical Developments: The emergence of complex behaviors and anatomical features, such as the ability to walk upright, the use of tools, and social structures, played pivotal roles in distinguishing modern humans from their ancestors. For instance, Neanderthals are noted for their sophisticated hunting strategies and possible use of fire.
• Genetic Interactions: The interbreeding between Homo sapiens and other hominins, particularly Neanderthals and Denisovans, is emphasized, suggesting that these interactions contributed to the genetic diversity observed in contemporary human populations.
• Survivorship and Extinction: The reasons behind the extinction of various hominin species, including environmental changes and competition with Homo sapiens, are considered, raising questions about the adaptability and superiority of modern humans.

These assertions collectively underscore the notion that human evolution is a dynamic and multifaceted process shaped by environmental pressures, genetic exchanges, and behavioral adaptations.

• [00:26] "Human evolution isn't actually linear. It's much more complicated than that..."
• [01:09] "What we see from this whole fossil record... is that human evolution is a process of diversification."
• [14:26] "We really don't have the answer. We don't know if our species got lucky or whether there was a real element of... superiority in our brains or our behavior."

The transcript refers to various types of evidence that support the claims regarding human evolution. These include:

• Fossil Records: The speaker discusses the significance of fossil discoveries, such as those belonging to Neanderthals and Homo erectus, which provide insights into their anatomical features and behaviors. For example, the Neanderthals are noted to have left behind numerous complete skeletons and behavioral information.
• Genetic Evidence: The analysis of DNA plays a crucial role in understanding the relationships between different hominin species. The speaker notes that everyone outside of Africa has a bit of Neanderthal DNA due to ancient interbreeding, highlighting the genetic legacy these species have left on modern humans.
• Archaeological Finds: Specific archaeological discoveries, such as stone tools and evidence of fire usage, are mentioned. For instance, Neanderthals are said to have created fire and used tools, demonstrating their cognitive capabilities and adaptations to their environments.
• Comparative Studies: There are references to behavioral and anatomical comparisons with other primates, particularly regarding brain size and complex behaviors. The speaker notes that Neanderthals had brains similar in size to modern humans, challenging preconceived notions about intelligence.

These pieces of evidence collectively contribute to a broader understanding of human evolution, emphasizing the intricate web of interactions and adaptations that have shaped our species.

• [01:05] "What we see from this whole fossil record and indeed the genetic record is that human evolution is a process of diversification."
• [09:00] "Everyone outside of Africa has a little bit of Neanderthal DNA in their genomes from ancient interbreeding 40 or 50,000 years ago."
• [13:00] "We think they're the first species to control fire, for example, which is critical... for cooking, warmth, community building, and warding off predators."

The transcript highlights several aspects concerning the reliability and certainty of the data discussed in the study of human evolution. It acknowledges that the field of paleoanthropology is marked by a dynamic and evolving landscape, where new discoveries continually reshape our understanding of our ancient ancestors. The speaker notes that many discoveries often lead to debates, indicating a level of uncertainty within the scientific community. For instance, the speaker mentions, [02:31] "...the behavior is so strange it's still dividing scientists today," suggesting that while some findings are groundbreaking, they do not come without controversy.

Additionally, the transcript refers to the gaps in the fossil record and the inherent scarcity of evidence. The speaker states that one could go through life without encountering fossilized remains, which emphasizes the fragility of the evidence available to researchers. This scarcity creates challenges in drawing definitive conclusions about our evolutionary path. The speaker elaborates that, [01:01] "...it's exploding," referring to the recent surge in discoveries, but also hints at the historical difficulty in accessing substantial data, as seen in the context of the Neanderthals and their coexistence with Homo sapiens. The mention of potential future discoveries in island Southeast Asia also indicates that our knowledge is far from complete and that ongoing research may fill in these gaps.

•  
  • [01:01] "...you could go your entire life and never make one of these discoveries."
  • [02:31] "...the behavior is so strange it's still dividing scientists today."

The transcript is rich with references to scientific debates and competing hypotheses within the field of anthropogeny. One of the primary discussions revolves around the interrelationships between various ancient human species, particularly the Neanderthals and Homo sapiens. The speaker notes the complexity of human evolution characterized by a diversification process, challenging the traditional linear narrative often depicted in educational materials. This complexity is underscored by the statement that [05:50] "Neanderthals weren't dummies," which addresses misconceptions regarding their intelligence and capabilities.

Another significant debate mentioned involves the reasons behind the extinction of Neanderthals and other ancient species. The speaker poses several questions, such as whether climate change, disease, or competition with Homo sapiens played crucial roles in their disappearance. The discussion highlights the uncertainty in the scientific community regarding these factors, stating, [08:35] "Did we outcompete them? Or perhaps an unspoken alliance was formed?" This rhetorical questioning illustrates the complexity of interpreting evidence and the various perspectives scientists hold.

Furthermore, the emergence of new species, such as the Denisovans, raises additional questions regarding their interactions with other hominins. The transcript indicates that the DNA analysis of these ancient humans has led to debates about their physical appearance and behaviors, showcasing that the field is rife with ongoing discussions that scientists are actively exploring.

•  
  • [05:50] "Neanderthals weren't dummies."
  • [08:35] "Did we outcompete them? Or perhaps an unspoken alliance was formed?"

[00:00] For most of us, the story of human
[00:01] evolution feels straightforward,
[00:03] inevitable, kind of familiar. If I was
[00:05] to ask you to conjure up in your mind
[00:07] the image [music] that most represents
[00:10] human evolution, it would probably be
[00:12] that much of progress illustration. One
[00:14] species leads to another species leads
[00:16] to another species until eventually we
[00:19] homo sapiens [music] enter the scene and
[00:21] it is game over for everyone else. Only
[00:24] it turns out that human evolution isn't
[00:26] actually linear. [music] It's much more
[00:28] complicated than that because this is
[00:30] the only time in our species history
[00:33] that only one species of human walked
[00:35] this earth. We previously for tens of
[00:37] thousands of years shared the planet
[00:40] with many, many other species of human.
[00:43] Some were stronger than us, some were
[00:45] tall, some were tiny, some were
[00:47] incredibly [music]
[00:48] smart. Today, with the help of some of
[00:50] the leading experts in the field,
[00:52] >> you have to remember that you could go
[00:54] your entire life and never make one of
[00:55] these discoveries. not even a piece, not
[00:57] even a tooth.
[00:59] And yet now we're in this period where
[01:01] it's exploding.
[01:03] >> So what we see from this whole fossil
[01:05] record and indeed the genetic record is
[01:07] that human evolution is a process of
[01:09] diversification.
[01:10] >> We introduce you to six ancient human
[01:12] species we once lived alongside, hunted
[01:15] alongside, and in some cases even had
[01:18] children with. [music] From the
[01:19] intelligent Neanderthalss to the island
[01:21] dwarf hobbits to the long-lost Denisvens
[01:24] who gifted millions of us with their
[01:26] genes, this is the real story of the
[01:28] extended human family tree most of us
[01:31] never learned about in [music] school. A
[01:33] lot of the things that we think make us
[01:35] uniquely human aren't actually unique at
[01:39] all. In fact, some of them we actually
[01:41] got from these earlier species. Now,
[01:44] many of our ancient cousins were so
[01:46] similar to us modern humans, but some
[01:48] were true evolutionary oddballs. So,
[01:51] let's play a game. Which of these
[01:53] species are the most surprising? We'll
[01:55] keep score along the way, and in the
[01:57] end, we will crown a champion. We're
[02:00] going to cover the gamut. From the birth
[02:02] of paleo anthropology almost 200 years
[02:04] ago when a discovery was made that was
[02:07] so baffling that it took decades [music]
[02:09] to understand its full implications up
[02:11] to the present day which many of us
[02:13] would argue is the golden age of the
[02:15] [music] study of paleo anthropology. The
[02:17] discoveries that are being made today
[02:18] are often baffling and always lead to
[02:21] debate, [music]
[02:22] including about one ancient human
[02:26] species whose behavior is so strange
[02:28] it's still dividing scientists today.
[02:31] Well, I think the fact that it's there
[02:32] at all, the fact that Fizianis is on
[02:34] this small island isolated suggests that
[02:37] there could be many more examples of
[02:40] species like this to be discovered in
[02:42] island Southeast Asia. So this
[02:43] experiment in human evolution that
[02:45] happened on Flores could have happened
[02:46] on many of the other islands as well. So
[02:48] there could be many more exciting
[02:50] discoveries to come.
[02:51] >> While some of these species may have
[02:52] vanished without a trace, some have
[02:55] legacies that are alive and well. As
[02:58] you're about to see, the homogenous is
[03:00] anything but [music] homogeneous. And
[03:03] the saga of our ancestors is anything
[03:05] but ancient history. The brains. What
[03:09] separates humans from all other
[03:11] creatures, large and small, that helped
[03:13] us spread to every corner of the world?
[03:16] Now, many would say it's down to our
[03:18] large and complex brains. Homo [music]
[03:21] sapiens, Latin for wise men. I love that
[03:24] we gave ourselves that particular name.
[03:26] But then again, we had mastered fire. We
[03:28] could make stone tools. We built the
[03:30] pyramids. How special are we? For
[03:33] millennia, we have reigned supreme as
[03:36] the last human species [music] standing
[03:38] and also it was long assumed the only
[03:41] one. All that changed though in 1829,
[03:44] even if no one realized it at the time.
[03:48] That year, amateur scientists entered a
[03:50] cave in Belgium and stumbled upon an
[03:52] unusual skull. Now, the explorers
[03:54] identities are unknown. The significance
[03:57] of their find was utterly lost on them
[03:59] as well. They assumed it belonged to
[04:02] some long deadad person who'd suffered
[04:04] from maybe disease or deformity. Now
[04:07] some historical context. Darwin had not
[04:10] yet published on the origin of the
[04:11] species. That would not happen for
[04:13] another 30 years. The word dinosaur
[04:15] wasn't coined for another decade. And
[04:18] the idea of evolution or for that matter
[04:21] extinction was heretical to the
[04:24] widespread western world view which
[04:26] longheld creation as it is described in
[04:31] the Old Testament. But then 27 years
[04:33] later, quarry workers uncovered more
[04:36] bones in the Neander Valley in Germany.
[04:39] And this time the world took notice.
[04:42] Long before homo sapiens, a species
[04:44] arose that was in many ways our equal
[04:47] and in others even more than that. Chris
[04:50] Stringer is a leading British paleo
[04:52] anthropologist at London's Natural
[04:54] History Museum. He has spent decades
[04:56] unraveling the story of our species and
[04:59] others.
[04:59] >> So Neanderls, of course, are really the
[05:02] best known ancient humans. We've got a
[05:04] lot of material from sites in in Europe
[05:06] and Asia, nearly complete skeletons and
[05:08] a lot of behavioral information. And
[05:09] what's interesting about them, of
[05:10] course, is they are very evolved humans.
[05:13] >> Homo Neanderthalencis came into its own
[05:16] around half a million years ago. Their
[05:18] ancestors migrated from Africa into
[05:20] Europe and Asia. Their men stood at
[05:23] around 165 cm tall. That's about 5 1/2
[05:28] ft. So that is shorter than your average
[05:31] modern human today. Although it's more
[05:34] in line with, let's say, Europeans from
[05:36] the Middle Ages. They were strong. They
[05:39] were incredible Ice Age hunters. They
[05:42] traversed long distances. They were
[05:43] probably built for endurance. They had
[05:46] dense bones, thicker muscle mass than
[05:48] most of us. And let me show you their
[05:52] profile. You might think that they
[05:53] [clears throat] have really prominent
[05:55] foreheads. Well, they have very, very
[05:56] prominent forebrows, but the forehead
[05:59] itself, look at it.
[06:02] It recedes.
[06:05] It's actually the opposite of a
[06:08] protruding or prominent forehead, but
[06:11] it's what's behind the bones that you
[06:15] might find most surprising.
[06:17] >> They walked as upright as we do that
[06:18] brains as large as ours. They had
[06:20] complex behavior.
[06:21] >> Brains don't [music] preserve in the
[06:23] fossil record, but the brain case does.
[06:25] And it suggests that Neanderthalss
[06:28] boasted brains very similar in size to
[06:31] our own brains, which seems shocking
[06:33] [music] because if they have big brains
[06:35] too, where are they?
[06:37] >> Not that bigger brains are more
[06:39] intelligent, but certainly with more
[06:42] neural connections [music] and so on,
[06:45] you become a more creative species.
[06:48] >> How might we know this? many potential
[06:51] answers lie in their skulls
[06:53] >> cuz that's that's how we all identify
[06:56] each other. We identify each other by
[06:58] looking at each other's skulls. We don't
[07:00] look at someone's knee and say, "Oh, how
[07:03] nice to [music] see you, Glattus." So
[07:05] skulls have all the clues about who we
[07:07] are. The shape of the Neanderthal skull
[07:10] suggests [music] the region of the brain
[07:12] associated with vision and physical
[07:14] coordination were especially large
[07:17] relative to the frontal lobe which
[07:18] [music] is the area responsible for
[07:20] reasoning. Still, contrary to modern
[07:22] connotations associated with their name,
[07:25] Neanderthalss weren't dummies.
[07:27] >> [music]
[07:27] >> And recently there's evidence that at
[07:29] least 400,000 years ago in Britain,
[07:32] people probably early Neanderals were
[07:34] making fire at the site [music] of
[07:36] Barnum in Suffukk. There are traces of
[07:39] fire. There are traces of stone tools
[07:41] that have been cracked by being in that
[07:43] fire. And there are even pieces of iron
[07:45] pyite. And this is a mineral which we
[07:47] know can be used. It can be struck by
[07:50] stone to make sparks [music] and then
[07:52] give rise to fire. And that iron pyite
[07:54] is not native to the area. [music] So,
[07:56] it's been imported to the site and we
[07:58] think those people were making fire
[08:00] there 400,000 years ago and yet they're
[08:03] not here. So, there's one of that longl
[08:04] lasting questions is, you know, why are
[08:06] we here and not the Neanderthalss? So,
[08:09] why aren't there any Neanderthalss left?
[08:11] The truth is, no one really knows for
[08:14] sure. But our best guess is that they
[08:16] all went extinct around 40,000 years
[08:19] ago.
[08:19] >> But it wasn't long after our appearance
[08:22] in Europe that Neanderls vanished. Uh,
[08:26] was there a tropical disease? Was did we
[08:29] simply uh outbreed them? Was climate
[08:33] change involved that it was getting
[08:34] warmer?
[08:35] >> Did we out compete them? Or perhaps an
[08:37] unspoken alliance was formed? At this
[08:40] point, we simply can't be sure. It is
[08:42] tempting to picture one ancient human
[08:45] species passing on the baton to another.
[08:48] Neanderthalss and homo sapiens, however,
[08:51] coexisted on this earth for over 200,000
[08:55] years. And we did more than simply cross
[08:57] paths.
[08:58] >> Everyone outside of Africa has a little
[09:00] bit of neanderal DNA in their genomes
[09:02] from ancient interbreeding 40 or 50,000
[09:05] years ago.
[09:06] >> Everyone with ancestry from outside of
[09:08] subsaharan Africa [music] have about 2%
[09:11] Neanderthal DNA in them. In fact, some
[09:13] people within subsahara and Africa also
[09:15] have Neanderthal DNA. But here's the fun
[09:17] part. They don't all have the [music]
[09:19] same 2%. Collectively, scattered through
[09:22] the DNA of modern humans today, we find
[09:24] as much as 20% of their total genome, a
[09:28] living vestage of a vanished species.
[09:31] Meaning, if someone has ever called you
[09:34] a bit of a Neanderthal, they might
[09:36] actually be right.
[09:37] >> You know, Neanderal is used an insulting
[09:39] term. Politicians with with reactionary
[09:42] policies are called Neanderal. Soccer
[09:43] hooligans are called Neanderal. And I
[09:46] think that's an insult to the Neandals.
[09:48] Um, they were very evolved humans in
[09:49] their own way. Uh, they walked upright
[09:51] as well as we do. They had brains as
[09:53] large as ours. They certainly had many
[09:55] elements of our complex behavior. So,
[09:57] they were certainly not uh the the
[09:59] traditional caveman beastlike image.
[10:02] >> So, how close were they to [music] us?
[10:05] Very. They are our sister species,
[10:09] likely our closest relatives. so similar
[10:12] to us that some of our ancestors
[10:14] interbred with them and many of us are
[10:16] the result of those let's say diances
[10:19] and so when it comes to giving them a
[10:22] score
[10:24] how surprising were they really they
[10:26] were so similar to us that they're not
[10:28] really that surprising at all I'd
[10:30] probably give them a three out of 10 but
[10:33] in of itself the fact that they are so
[10:36] similar to us should blow our minds
[10:39] because to think [music] that an ancient
[10:41] species was so similar to us and no
[10:43] longer is with us is in of itself
[10:45] fascinating to me.
[10:47] >> The survivor [snorts] well before the
[10:49] Neanderthalss came the ancestor of them
[10:52] all really the greatest survivor our
[10:56] genus has ever known Homo erectus. Now
[11:00] to be clear they didn't invent
[11:02] bipedalism which is walking upright on
[11:05] two legs. Other species before them were
[11:07] also doing it. But those earlier species
[11:10] were also in the trees. Whereas erectus
[11:13] was exclusively walking upright.
[11:16] >> As Darwin said, one of the cardinal
[11:18] features of being human, which is
[11:20] walking upright. A very strange mode of
[11:22] locomotion. There aren't many bipeds
[11:25] [music] on this planet. But certainly
[11:28] with 8 billion of us on the planet, it's
[11:31] been very successful. Back in 1890, what
[11:33] began as a hobby for a Dutch surgeon
[11:36] named Eugene Dubois blossomed into an
[11:38] all-consuming passion, one which would
[11:40] change the course of paleo anthropology.
[11:42] Captivated by Darwin, Dubois became
[11:44] obsessed [music] with finding a bridge
[11:46] species from ape to man. He abandoned
[11:50] his career and joined the Dutch colonial
[11:52] army just so he'd be sent to Southeast
[11:55] Asia where he believed his so-called
[11:57] [music] missing link might be found. And
[12:00] as you might have guessed it, he was
[12:02] kind of right. Now, as with the
[12:04] Neanderthal discoveries, skepticism
[12:06] again prevailed. Critics claimed the
[12:08] elongated feur Dubois uncovered belonged
[12:12] to Homo sapiens. But thanks to
[12:14] subsequent finds over 30 years later,
[12:16] Dubois's vision was vindicated. So this
[12:20] is an example of Homo erectus and but
[12:23] compared with us many more primitive
[12:25] features great big brow ridge a smaller
[12:27] brain a very angular cranium and [music]
[12:30] this is one of the really longest
[12:32] lasting of human species so examples of
[12:35] homo erectus are known from Africa at uh
[12:37] [music] more than one and a half million
[12:39] years ago and it seems to have survived
[12:41] as late as 100,000 years ago on the
[12:44] island of Java. So, a very successful
[12:46] species.
[12:46] >> With a track record that long, it is no
[12:49] surprise that Homo erectus claims many
[12:52] potential firsts amongst our ancestors.
[12:54] We think they're the first species to
[12:57] control fire, for example, which is
[12:59] critical, of course, for cooking,
[13:00] warmth, community building, and warding
[13:03] off predators. The excavation of a site
[13:05] inside a South African cave dating back
[13:08] 1 million years revealed evidence of
[13:10] [music] a repeated series of small fires
[13:13] all in the same spot.
[13:15] >> But in those early stages probably
[13:17] people were [music]
[13:18] capturing natural fires perhaps from
[13:20] volcanic eruptions perhaps from natural
[13:23] forest fires perhaps from [music]
[13:24] lightning strikes and they were then
[13:26] keeping that fire going as long as they
[13:28] could. But it took a long time, it
[13:31] seems, for people to develop the ability
[13:33] to make fire at will.
[13:34] >> Her erectus may also be able to claim
[13:36] the first major innovations of stone age
[13:40] technology such as handaxes and possibly
[13:43] [music] possibly also Earth's first
[13:45] artwork. The disappearance of Homoctus
[13:48] and other ancient human species just as
[13:51] Homo sapiens were coming into their own
[13:53] does seem to support this idea that we
[13:56] [music] simply out competed them. But a
[13:58] lot of research indicates that it is a
[14:01] much more complicated [music]
[14:02] and nuanced picture than that.
[14:04] >> So the pattern of human evolution
[14:06] overall for millions of years has been a
[14:09] diversity of species uh living at least
[14:12] in proximity to each other if not in
[14:14] exactly the same places. So there's all
[14:16] that diversity which is typical of the
[14:18] whole of human evolution until this last
[14:20] 30,000 years when we're left alone on
[14:23] the planet and [music] we're the only
[14:25] survivors of all these experiments in
[14:26] how to be human. We really don't have
[14:28] the answer. We don't know if our species
[14:30] got lucky or whether there was a real
[14:33] element of, if you like, superiority in
[14:36] our brains or our behavior that led us
[14:38] take over the planet and cause these
[14:40] other species to die out. So, it's still
[14:43] unclear to what extent we were
[14:44] responsible for the extinctions directly
[14:46] [music] of these other human species. In
[14:49] the case of Hermerectus, it's possible
[14:51] they failed to adapt as the grasslands
[14:54] in which they had flourished grew into
[14:56] less forgiving jungle. Or maybe [music]
[14:58] they failed to compete with smarter
[15:00] species capable of fashioning more
[15:02] advanced tools and formulating superior
[15:05] hunting strategies. But maybe, just
[15:08] maybe, after their enormously long day
[15:11] in the sun, 2 million years on this
[15:13] planet, that's 10 times longer than we
[15:16] homo sapiens have existed on Earth.
[15:20] Maybe it was simply their time. So, in
[15:23] [music] conclusion, how similar were
[15:25] Homo erectus to us? Well, if they hadn't
[15:29] have perfected their posture, our lives
[15:31] would be very, very different today. In
[15:34] fact, it's not just us that owes him
[15:36] that huge debt of gratitude. We think
[15:38] that many of the other human species
[15:40] that were around at the same time as us
[15:42] were also descended from that species
[15:45] Homo erectus. And it makes you think
[15:47] they are kind of remarkable and
[15:50] surprising. They make sense in terms of
[15:52] their place in the evolutionary tree.
[15:55] That longevity
[15:58] is slightly bonkers. And so I would
[16:00] probably give them a 6 out [music] of
[16:02] 10. the builder. Across the ancients, we
[16:05] find many reoccurring achievements using
[16:08] fire, for example, and making tools, but
[16:10] Homer Hydroenzis may be able to claim
[16:13] the achievement of the first homes built
[16:16] by human hands.
[16:17] >> So, Homer Haidobensis, and I've got an
[16:19] example here of from Cabway or Broken
[16:22] Hill. This is a replica of a fossil that
[16:24] was found back in 1921.
[16:26] >> In 1907, a German quarry worker happened
[16:29] upon a massive jawbone. An
[16:31] anthropologist determined this oversized
[16:34] and mostly chinless mandible belonged to
[16:36] a species distinct from any yet known.
[16:39] Naming this human ancestor after the
[16:41] town which it was found in, the
[16:43] so-called H Highleberg man, aka Homo
[16:46] Hidleberenis. The history of
[16:48] Homohyleberenzis may stretch back as far
[16:51] as 1.3 million years, but conservative
[16:54] estimates place their dawn closer to
[16:56] 700,000 years ago. The Homo H Highleberg
[17:00] male stood a relatively strapping 175 cm
[17:04] or 5'9. Compared to the earlier Homo
[17:08] erectus, the brain was larger,
[17:10] approaching modern human proportions.
[17:12] >> It's more derived than erectus, a larger
[17:15] brain, a more expanded cranium, but also
[17:17] still some primitive features. So the
[17:19] back of the skull has this strong ridge
[17:21] of bone like erectus with angulation and
[17:23] the cranium is not so expanded and
[17:25] filled out as it is in us or or
[17:28] neanderals. So a mixture of features and
[17:31] this seems to have been a very
[17:32] successful species certainly complex
[17:34] behavior in hydrogensis perhaps not as
[17:37] complex as ours or neanderals or longi
[17:39] but certainly more complex than erectus.
[17:42] Proof of Homer H Highleberg's complex
[17:44] reasoning and physical abilities lie
[17:46] most dramatically in how they address
[17:49] the need for shelter.
[17:50] >> In terms of behavior, we think that
[17:52] Hydeensis did have complex behavior. The
[17:54] brain is certainly approaching the
[17:56] levels of of people today and Neandertos
[17:59] um and we look at something like like
[18:00] this and we've got examples of
[18:02] Haidobensis even from Britain uh
[18:04] probably from the summit of Boxgrove
[18:06] from about 480,000 years ago. Homoid
[18:09] Beenza's homes may have been built with
[18:11] wooden poles or bones fixed in place by
[18:14] heavy stones [music] and we think they
[18:16] were covered with animal hides or
[18:19] branches. One H Highleberg's community
[18:21] discovered in Germany and approximately
[18:24] [music] 400,000 years old may have even
[18:27] featured fences perhaps to keep large
[18:29] predators out or to contain freshly
[18:31] captured game until it was time to
[18:33] feast. Homo had begun may have [music]
[18:35] been the first big game hunters.
[18:38] >> And there we've got evidence that these
[18:41] people were able to hunt actively horse,
[18:43] deer, probably even rhinos. They were
[18:45] butchering all these animals at the
[18:47] site, making uh beautiful hand axes and
[18:50] then systematically dismembering these
[18:53] carcasses, getting all the meat off of
[18:54] them in what was a dangerous landscape
[18:56] with many dangerous wild animals around.
[18:58] So they were kind of possessing that
[19:00] carcass and fully in control of that
[19:02] local environment.
[19:03] >> Homo hydroleenzis migrated [music]
[19:05] throughout Europe.
[19:06] >> Opinions differ about what's in
[19:08] haidensis, how widespread it was, but in
[19:10] my view, hide against was a long live
[19:12] species. It was present in Europe and
[19:14] Asia and Africa.
[19:16] >> Their trail goes cold some 200,000 years
[19:19] ago. And the usual suspects may well
[19:21] apply. Climate change, food scarcity,
[19:24] disease, competition. But some
[19:26] scientists would argue that their story
[19:28] never ended because for them hidelenzis
[19:32] may have given rise to the Neanderthalss
[19:33] [music]
[19:34] and us. So in terms of how similar they
[19:37] are to us, well if they were our
[19:39] ancestors, very similar. But H
[19:42] Highleberg is in many ways a [music]
[19:45] mystery because were they our ancestor
[19:48] or weren't they? [music] So, in
[19:51] conclusion, when it comes to how
[19:53] surprising of a species are they, well,
[19:56] they were capable. They were not
[19:58] primitive, but it would be nice to know
[20:01] if they were our grandparents. So, I
[20:03] give [music] them a seven out of 10.
[20:05] >> And also, it provides a kind of
[20:07] evolutionary bridge between the more
[20:08] primitive erectus and the more derived
[20:11] humans, us and Longi [music]
[20:12] and Neander.
[20:14] >> The Hobbit. Up till this point, we've
[20:17] covered what might be called the first
[20:19] golden age of paleo anthropology. So
[20:21] from the mid [music] 19th century
[20:23] through to the turn of the 20th century,
[20:25] scientists had unearthed and analyzed
[20:27] evidence proving that homo sapiens both
[20:30] sprang from and once shared the planet
[20:33] with other [music] human species. But
[20:35] then the new century brought in the
[20:37] second golden age of paleoanthropology
[20:40] with miniature skeletons, DNA
[20:42] bombshells, and possible mysterious
[20:45] rituals. And it all kicks off in 2003
[20:47] when paleo anthropology leaped back into
[20:50] the headlines with some very big news
[20:52] about some very small humans. Meet Homo
[20:55] Floresensis,
[20:57] aka the Hobbit.
[20:58] >> So Homo Floresensis is a remarkable
[21:01] species. um homophoresensis suggesting
[21:04] it's genus homohouan although I'm not
[21:06] sure it really is. Um but this is a
[21:08] really tiny species. This is the
[21:11] cranium. It has an apesized brain there.
[21:13] The whole [music] skeleton suggests
[21:15] these individuals. Some of them were
[21:16] barely more than a meter tall as adults.
[21:19] So this is very smallbodied small brain.
[21:21] So it looks like a completely separate
[21:23] line of evolution that evolved [music]
[21:25] there for hundreds of thousands perhaps
[21:27] even a million years. Inside a cave on
[21:29] Indonesia's Flores Island, a joint
[21:31] Indonesian on Australian research team
[21:34] was stunned to find a nearly complete
[21:37] and extremely petite skeleton of an
[21:39] adult female who lived and died about
[21:42] 80,000 years ago. The typical adult
[21:45] homoizenzis stood on average of 3 and
[21:48] 1/2 ft tall. So that's about 105 cm and
[21:51] weighed all of about 30 kg or [music] 65
[21:55] lb. The origin of this species of course
[21:57] is still unknown. Some people believe
[21:59] it's a dwarf form of Homo erectus. So it
[22:02] may have come from somewhere like Java.
[22:04] But others and that includes me think
[22:06] that it's something much more primitive.
[22:08] It may be a relic of a group that spread
[22:10] into the region maybe 2 million years
[22:12] ago and then evolved for a long time in
[22:15] isolation. Homo floresensis was likely
[22:18] pintsized because of this incredible
[22:20] phenomenon known as island dwarfism
[22:22] which basically means that on an island
[22:24] the large animals get smaller thanks to
[22:28] a reduction in resources but weirdly the
[22:31] small things on the island get bigger
[22:34] because [music] there are less predators
[22:35] on that island. Homo floresientists
[22:38] challenges many of the assumptions about
[22:41] ancient [music] human species not only
[22:43] in regards to their physical stature but
[22:45] in their brain size and therefore brain
[22:48] power and capabilities. Now we typically
[22:50] equate brain size with intelligence and
[22:53] we humans are supposed to be intelligent
[22:56] and yet somehow homophorizes
[22:59] has a brain the size of the brain of
[23:02] chimpanzees
[23:04] and yet they were able to make stone
[23:07] tools. So really it does challenge what
[23:10] we think it is to be [music]
[23:12] human.
[23:13] >> So I think that in terms of its behavior
[23:15] homo floresensis was much less like us.
[23:18] [music] I think it although it's using
[23:20] stone tools I think its way of life is
[23:22] much simpler and I think it really
[23:23] wasn't showing the complexity of
[23:25] behavior that we find in us in the
[23:27] Neanderles.
[23:28] >> How and why did homophoresensis
[23:30] disappear 50,000 years ago. So it turns
[23:32] out they weren't the only striking and
[23:35] exotic species on the island of Flores.
[23:37] So from what we know of Florizens, yes,
[23:39] it was using stone tools and it was
[23:41] eating meat and obviously plant
[23:43] resources as well, but it may well have
[23:45] got much of its food from scavenging the
[23:47] kills of Komodo dragons, which were the
[23:50] main predator on the island of Flores.
[23:51] [music]
[23:52] >> In addition to those giant lizards,
[23:53] there were also species of giant stalks
[23:56] and giant [music] rats. And if it was
[23:59] acquiring its own food by hunting, it
[24:02] probably was getting things like giant
[24:04] rats and much smaller beasts than the
[24:06] large animals on the island.
[24:08] >> Homophoresensus' diet may also have
[24:10] depended on a another island um
[24:14] creature, a rather remarkable
[24:16] elephantlike mammal called a stegodon
[24:19] that on this island was so small, so
[24:22] dwarfed that it was the size of a cow.
[24:25] And so you have a human the size of a
[24:29] 4-year-old hunting elephant-like
[24:31] creatures the size of cows on this
[24:33] island. The stegodons died out, possibly
[24:35] even hunted to extinction. And when that
[24:37] happened, the problem it presented for
[24:39] homo floresiansis might have [music]
[24:41] been anything but small. Now we're not
[24:43] sure why homopesis went extinct. The
[24:45] stegodons might have been a contributing
[24:47] factor, but volcanic eruptions do look
[24:50] like they were incredibly detrimental.
[24:52] It's also possible that we were a final
[24:54] nail in the coffin. And the final
[24:56] question, how surprising are they as a
[24:59] human species?
[25:00] >> So I think for Floriziansis, of course,
[25:02] there's the whole question of whether it
[25:03] is human. The name Homo Floresensis
[25:05] implies it is, you know, a member of the
[25:08] genus Homo, which I call human. But in
[25:10] fact, many of its features are much more
[25:12] primitive, more apeike. It suggests it
[25:15] was probably still spending time in the
[25:16] trees. In many ways, I doubt that it
[25:19] really is showing human features in the
[25:20] way that say Neandertos or Holongi are
[25:23] showing human features.
[25:24] >> Well, they're humans the size of
[25:26] fouryear-olds making stone tools and
[25:28] hunting elephant like creatures on an
[25:30] island. [music] So, I'm going to go for
[25:32] a 10 out of 10 for surprising or an 11
[25:36] out of 10 or 100 out of 10. [music]
[25:38] The Enigma. So if it wasn't for modern
[25:41] DNA analysis, it is not clear when we
[25:44] would have discovered the Denisven, a
[25:47] remarkable species that does blow my
[25:50] mind.
[25:51] >> So I've got here a replica of the
[25:53] harbing cranium and we're pretty sure
[25:55] that this is the most complete fossil of
[25:58] a denisan that we've got.
[25:59] >> So in 2010, a bone, a finger bone to be
[26:03] precise, was sent off for analysis in a
[26:07] German laboratory. Now this particular
[26:09] finger bone came from a Neanderthal in
[26:12] Denisa cave in Siberia and they crushed
[26:14] it up to analyze its DNA [music] only
[26:18] they extracted its DNA but it wasn't
[26:21] Neanderthal DNA that they found and it
[26:24] also wasn't homo sapiens DNA but it was
[26:27] human DNA. So it turned out that this
[26:29] fingerbone belonged to a human that was
[26:32] as yet an undescribed unknown species to
[26:36] science but it was human. And so the
[26:38] question was who were the mysterious
[26:41] Denisans? The analysis of Denisven DNA
[26:45] showed that their DNA is inside many
[26:48] many modern humans living today. In fact
[26:51] Tibetans who are able to live at very
[26:53] high altitude are able to live at high
[26:55] altitude. Turns out because of a
[26:57] mutation that they picked up off
[26:59] Denissance. [music]
[27:01] >> So these people were widespread across
[27:03] eastern Asia, very successful living in
[27:06] a range of environments up in northeast
[27:08] China, [music]
[27:09] in Siberia, up on the Tibetan plateau.
[27:12] And from their DNA, we think that they
[27:14] were also down in places like Ireland,
[27:16] Southeast Asia. [music]
[27:17] >> The big question remained, what did the
[27:19] Denisans actually look like? Because we
[27:22] didn't really have a fossil for them.
[27:25] Now there was one part of a jaw that
[27:27] [music] was found in Tibet by a monk and
[27:32] upon further analysis [music] it turned
[27:34] out to be a denissant but it was only a
[27:36] part of the jaw. It wasn't the full
[27:38] face. [music]
[27:39] >> It is very much like one of those
[27:41] detective shows seeking evidence and
[27:44] trying to identify clues [music] that
[27:48] will allow us to interpret the lifestyle
[27:51] or the anatomy of these creatures.
[27:53] [music] And so the mystery continued. It
[27:56] became almost like the golden chalice
[27:59] was the holy grail of paleo
[28:01] anthropology. [music]
[28:02] What did the Denisans look like? And
[28:04] then another discovery was made in
[28:06] Denisa cave. Again, a bit of bone was
[28:09] analyzed and it was found [music] to
[28:11] have a Neanderthal parent and a Denisven
[28:14] parent. And so we effectively had a
[28:17] hybrid individual. Now they called this
[28:19] girl Denny. But again, we still had no
[28:21] [music] face for the Denisven. And then
[28:24] in 2001, a skull [music] was analyzed
[28:27] that they called Dragon Man. Now, there
[28:29] is a whole story behind this skull. It
[28:31] was apparently found at the bottom of
[28:32] the world, but some people question this
[28:34] [music] story cuz it goes all the way
[28:35] back to World War II. But when they did
[28:37] the analysis, they were able to confirm
[28:40] that it was a new species [music] called
[28:41] Homo Longi. But when they did the DNA
[28:44] analysis, they were able to confirm that
[28:46] it was also [music] a Denisven. So we
[28:48] finally knew what the Denisans actually
[28:51] looked like. By the way, [music] they
[28:54] looked a bit like Neanderthalss, but
[28:56] perhaps a bit more robust, a bit kind of
[28:58] more rugged, shall [music] we say. And
[29:00] so when it comes to how similar they are
[29:02] to us, honestly, like the Neanderthalss,
[29:04] their DNA lives on in many, many of us
[29:07] walking around today. The denisan seem
[29:09] to have been capable of living in very
[29:11] cold conditions in high altitude
[29:13] conditions and also down in the south of
[29:15] Asia and island Southeast Asia in
[29:17] tropical and subtropical conditions. So
[29:19] for example, it seems to have helped
[29:21] populations adapt to high altitude
[29:23] conditions in Tibet and down in island
[29:25] Southeast Asia. It's certainly part of
[29:28] disease protection uh down there helping
[29:31] the immune systems. So they're
[29:32] incredibly similar to us because clearly
[29:35] [music]
[29:35] our ancestors were at times frolicking
[29:39] with the Denisven. They're also very
[29:41] similar to us in many kinds of [music]
[29:44] uh technology and behavior. But when it
[29:48] comes to how surprising of a species
[29:50] they are, a species that was discovered
[29:53] from its DNA, I'd give that a solid 8
[29:56] out of 10 for surprising. The mourner.
[29:59] Now on first glance our final species
[30:01] may appear primitive compared [music] to
[30:03] modern humans but in homonyi we do find
[30:06] an echo of an attribute that is
[30:08] decidedly us.
[30:10] >> And here we've got examples of homonyi.
[30:14] So this is a really interesting species.
[30:16] We've only known about it in just really
[30:18] the last 10 years or so.
[30:19] >> They were in South Africa 2 to 300,000
[30:22] years ago. Their history may stretch
[30:24] back as far [music] as 2 million years.
[30:26] They are yet another thread in the
[30:28] tangled web of the so-called muddle in
[30:31] the middle. A phrase which we use to
[30:32] describe many different human species
[30:35] that existed in the middle plea scene
[30:37] whose relationship with each other and
[30:39] with us remains very unclear. The
[30:41] discovery of Hermoni is worthy of
[30:44] Hollywood. It begins in 2013 near
[30:46] Johannesburg inside the cradle of
[30:48] humankind. A world heritage site and as
[30:51] the name implies an established
[30:54] paleropological hotspot. A group of
[30:56] explorers spotted a narrow opening
[30:58] inside a cave which they discovered
[31:00] offered a small entrance [music] to a
[31:02] hidden chamber. Inside it the largest
[31:04] collection of a single homminin species
[31:07] ever found in Africa. One that lay
[31:09] undisturbed for hundreds of thousands
[31:12] [music] of years. Enter
[31:13] paleanthropologist Lee Berger.
[31:15] >> It had instantly become the richest
[31:18] fossil homminate site discovered in all
[31:21] of history on the continent of Africa,
[31:23] perhaps in the world. working in
[31:25] confines so claustrophobic only a team
[31:28] of small pale anthropologists known as
[31:30] underground astronauts could negotiate
[31:32] [music] them. The remains of at least 15
[31:35] ancient humans were painstakingly
[31:37] recovered. Hermani was small. Adult
[31:40] males stood at about 5 ft tall. So
[31:42] that's 150 cm. [music] On average they
[31:44] weighed about 100 lb or 45 kilos.
[31:48] >> Like homophorizensis it's got very small
[31:50] brain. This is an apesized brain here.
[31:53] And yet the teeth show, you know, quite
[31:55] derived features. They're quite small.
[31:57] [music] The diet seems to have been very
[31:58] humanlike. And yet this is a small brain
[32:01] creature with a skeleton that combines
[32:03] some humanlike features in, for example,
[32:05] the legs and the feet and the hands, but
[32:07] also some much more primitive features,
[32:10] suggesting that the creature was still
[32:12] spending a lot of time climbing uh maybe
[32:15] up on rocks, but also up in trees.
[32:17] >> While hermoni brains were not much
[32:19] larger than a chimps, they were
[32:21] asymmetrical. and the frontal loes were
[32:23] elongated each in ways that recall
[32:26] another species, namely [music] us. Some
[32:29] controversially believe that homeowner
[32:31] practice behavior previously thought to
[32:34] be unique [music] to modern humans and
[32:36] perhaps Neanderthals, symbolic and
[32:38] ritualized disposal of [music] the dead.
[32:41] A possibility which it turns out offers
[32:43] the suggestion that brain shape may
[32:46] [music] ultimately trump size. Now,
[32:49] given the location of those fossils,
[32:51] remote and hard to reach, a tantalizing
[32:54] theory holds that fellow homei
[32:56] intentionally put them there. Perhaps as
[32:59] a way of paying final respect. Is it
[33:01] possible these ancient and seemingly
[33:03] primitive creatures had a fully
[33:06] developed concept of a soul of an
[33:08] afterlife?
[33:09] >> It's claimed that Hommoni was engaging
[33:11] in very complex behavior, burying its
[33:13] dead, engraving the cave walls, and
[33:15] building fires deep in the cave. And
[33:18] that is still the subject to a lot of
[33:20] scientific debate. So I think for
[33:22] Homundi, one of the outstanding
[33:23] questions is how complex was its
[33:25] behavior with that small brain? And I
[33:27] think some of us really doubt that it
[33:29] could have had such complex behavior
[33:31] with basically an ape oropithesine sized
[33:34] brain. Um, and I think it really will be
[33:36] a big test of of of the whole question
[33:38] of why we have big brains because it's
[33:40] assumed, you know, brains are
[33:41] energetically very expensive. And it's
[33:44] assumed that evolution drove the
[33:46] development of larger brains along with
[33:49] complex behavior. Um, and if Nledi shows
[33:51] that complex behavior with such a small
[33:53] brain, it really raises the question of
[33:55] of how Nledi could even do that with
[33:58] that small brain. Lee Burgerer is more
[34:01] convinced on the idea that homeowner Lei
[34:03] deliberately buried their dead. Here he
[34:06] discusses what he sees as a clue, one
[34:09] left for us some quarter of a million
[34:11] years ago. Discovered in the deepest
[34:13] recesses of the rising star cave system.
[34:16] This little child's skull is a great
[34:18] mystery. It's found in one of the most
[34:20] inaccessible places and it's there
[34:23] alone. There are no parts of its body.
[34:25] There are no parts of its mandible. It's
[34:28] just [music] a skull and it appears to
[34:29] have been placed on a ledge in a place
[34:32] that's probably the most difficult place
[34:34] to get in the entire rising star cave
[34:37] system. Uh so it's a great mystery and
[34:40] we think possibly several hundred
[34:42] thousand years ago a homonyi placed that
[34:44] child's skull there.
[34:46] >> Burger notes that in his experience one
[34:48] rarely finds bones of any one species
[34:52] without finding remains of others close
[34:54] by. During the expedition itself, only
[34:57] hominids were coming. There's always
[34:59] other stuff. There was no other stuff.
[35:02] They were alone.
[35:03] >> If Burger is correct, the implication
[35:05] could hardly be bigger.
[35:07] >> We've already claimed that this is a
[35:09] site of deliberate bodies disposal. What
[35:12] I think a lot of people may not really
[35:14] understand is if that's true, then
[35:16] Homoleti is already operating at a level
[35:19] that we're not claiming for Homo sapiens
[35:21] for another 200,000 years. [music] It's
[35:23] already operating at a level that
[35:26] borders on the symbolic likely.
[35:28] >> Why might Home and Ali have ritually
[35:30] buried their [music] dead? For the same
[35:32] reason we still do today.
[35:34] >> Why? Cuz we spend all our time trying to
[35:37] explain why we're separate from [music]
[35:38] nature. And so did our ancestors. And
[35:42] all of them did it in the past. They saw
[35:43] themselves as separate from nature and
[35:45] separated. They didn't want bodies going
[35:47] undergoing those
[35:48] >> [music]
[35:48] >> uh natural processes for whatever
[35:50] reasons. And that does vary. But it's
[35:52] almost a universal truism in human
[35:54] behavior into the relatively deep past
[35:56] where we know they're humans. So if it's
[35:58] true in homonyi, then it's astounding.
[36:01] [music] Beyond questions regarding
[36:03] potential burial practices, many other
[36:05] fundamental mysteries remain surrounding
[36:07] homonyi. [music]
[36:08] >> The questions that we all have. Is
[36:12] homonyi related to us? But did homonyi
[36:15] ever meet [music] Homo sapiens? Or maybe
[36:17] more appropriately, did homo sapiens
[36:19] ever meet homonyi? And if so, what
[36:22] happened? We don't have an answer for
[36:24] that yet. Is Homonyi that elusive
[36:27] species X that interbred with modern
[36:29] humans in Africa around 200,000 [music]
[36:32] years ago?
[36:34] Is homonyi
[36:36] another thing that is related to us and
[36:39] not species X? And how is it [music]
[36:41] related to us? Is homttleti not related
[36:44] to us at all? That would almost be more
[36:46] remarkable.
[36:48] And yet homonyleti is so primitive. It
[36:50] would be remarkable.
[36:52] There's no no answer that's not going to
[36:55] be striking within that.
[36:58] >> The bad [music] news is the answers to
[37:00] many of our questions are as yet
[37:02] unknown. The good news, as only small
[37:05] sections of Hermoni's caves have been
[37:07] excavated, there's reason to hope the
[37:09] answer [music] to this and many other
[37:11] mysteries still waits us inside their
[37:14] walls. If it could hide from us, if it
[37:17] could remain and invisible from us
[37:20] [music] for likely millions of years as
[37:23] it existed in parallel to all these
[37:25] other things we're finding, other things
[37:27] could too. There's more out [music]
[37:30] there to find.
[37:31] >> We asked the question one final time,
[37:33] how close were they to us? A potentially
[37:36] well-developed spiritual side helps
[37:38] their case immensely. However, whether
[37:41] they really did have a spiritual side is
[37:43] one of the most hotly debated questions
[37:45] in the field, which helps me when it
[37:47] comes to [music] scoring how surprising
[37:49] of a species they are. Because if they
[37:51] are doing that, tiny brains practicing
[37:55] spirituality or shamanism,
[37:58] that is a 9 and a half out of 10 for me.
[38:01] When it comes to the homogenous, that
[38:02] which unites us all may ultimately trump
[38:05] that which made [music] each ancient
[38:07] human species unique. But in conclusion,
[38:10] which species is the most surprising?
[38:12] Denisven, sure. NDI, why not? Homo
[38:15] floresiansis, the hobbit, definitely.
[38:18] But perhaps the most surprising is that
[38:20] they existed [music]
[38:22] collectively alongside us. And which
[38:26] ultimately of all of these species bears
[38:28] the closest resemblance to our species,
[38:30] [music] it would probably be between the
[38:32] Neanderthals and the denissipants.
[38:35] Now, [music] in each of the ancient
[38:37] species with whom we once shared the
[38:39] planet, we see elements of ourselves.
[38:41] Some, like the Denisvens and the
[38:43] Neanderthalss have been shown to
[38:45] literally live on in contemporary human
[38:48] DNA. [music]
[38:49] And as research and genetic testing
[38:51] improves, it's likely others will join
[38:53] their ranks.
[38:54] >> So, I think the evidence suggests that
[38:56] we and the Neanderles and Homolongi
[38:58] diverged probably more than a million
[39:00] years ago. Our Linges went their
[39:02] separate ways. Neander was evolving in
[39:04] Western Eurasia. us evolving in Africa
[39:06] most of the time and the longe denisman
[39:09] lineage evolving over in eastern Asia
[39:11] but now and again these lineages came
[39:13] together and did some interbreeding and
[39:15] certainly within the last 60,000 years
[39:17] as homo sapiens spread more widely there
[39:20] was distinct episodes of interbreeding
[39:22] with neanderals in the west that was
[39:25] then carried around the whole of the
[39:27] rest of the world as as homo sapien
[39:29] spread but also over in the far east and
[39:32] island southeast Asia there were
[39:33] separate phases of interbreeding with
[39:35] different groups of denisants and that
[39:37] DNA is found in humans today.
[39:40] >> Our genetic connection to the ancients
[39:42] is far more than academic. Interbreeding
[39:45] provided benefits for all parties
[39:47] involved.
[39:48] >> So what we see from this whole fossil
[39:50] record and indeed the genetic record is
[39:52] that human evolution is a process of
[39:54] diversification. And we've got these
[39:56] branching patterns of [music] species
[39:57] diverging from each other, adapting,
[39:59] developing different behaviors,
[40:01] developing [music] adaptations to live
[40:03] in particular environments, but it
[40:05] wasn't a complete separation because
[40:06] these branches now [music] and again in
[40:08] some places came together and exchange
[40:10] DNA. And this is a pattern we see today
[40:13] for closely [music] related species that
[40:15] they'll go their own way, but now and
[40:17] again, if they get the [music] chance,
[40:18] they will interbreed with closely
[40:20] related species and pick up a bit of
[40:22] diversity that they may have lost or
[40:24] [music] perhaps acquire some bits of DNA
[40:26] that are good for them that they hadn't
[40:27] yet evolved. With new DNA studies, what
[40:30] we're find out is they don't [music]
[40:32] all disappear. There's almost always
[40:34] some small introgression of DNA that
[40:37] gets captured by homo sapiens. And maybe
[40:39] that's our trick. Maybe we just keep
[40:41] breeding oursel into the better
[40:43] mousetrap. [music]
[40:44] >> The effects of ancient interbreeding can
[40:46] still show up in ways that surprise
[40:49] [music] us.
[40:49] >> It seems that some of these bits of DNA
[40:51] are linked with autoimmune diseases
[40:53] [music] in people today. And down in
[40:55] Ireland, Southeast Asia, it's certainly
[40:57] part of disease protection uh down there
[41:00] helping the immune [music] systems.
[41:02] >> Associations have been found with
[41:03] Crohn's disease, CO 19, immunities, and
[41:06] even addiction. [music]
[41:08] Ancient humans remain relevant to modern
[41:10] life. The past is never really gone.
[41:12] Given the [music] recent explosion of
[41:14] groundbreaking new discoveries, at least
[41:16] three possible new species have already
[41:19] been discovered in this very young
[41:21] century. So, who knows what or who else
[41:24] is still [music] waiting to be found.
[41:29] Well, I think the fact that it's there
[41:30] at all, the fact that Ferosiansis is on
[41:33] this small island isolated suggests that
[41:35] there could be many more [music]
[41:37] examples of species like this to be
[41:39] discovered in island Southeast Asia. So,
[41:41] this experiment in human evolution that
[41:43] happened on Flores [music] could have
[41:44] happened on many of the other islands as
[41:46] well. So, there could be many more
[41:47] exciting discoveries to come. The only
[41:49] thing we [music] absolutely know is that
[41:51] we're alone today.
[41:53] >> What else will we learn about our
[41:54] ancient ancestors? And what more can
[41:57] this tell us about ourselves?