(swishing) (piano music) - [Narrator] We are the paradoxical ape, bipedal, naked, large-brained. Long the master of
fire, tools and language but still trying to understand ourselves. Aware that death is inevitable, yet filled with optimism. We grow up slowly. We hand down knowledge. We empathize and deceive. We shape the future from
our shared understanding of the past. CARTA brings together experts
from diverse disciplines to exchange insights on who
we are and how we got here. An exploration made possible by the generosity of humans like you. (pleasant music) - So, this is my show-and-tell. Every single cell in our body
is packaged with my toolkit, which is DNA, and we have two types of DNA that carries the blueprints
that we all walk with. And I know to this audience this is like kindergarten school, but I'm showing this to remind
us that I'm going to talk about two different types of inheritance, the nuclear DNA which
is, the chrome makes up the chromosomes that undergoes
mixing at cell division or recombination that is
now why I am at this height and at this size. You heard about brain size and
height and weight, et cetera. Well, I am your show and
tell for all of that today. In addition, small is
packaged and dangerous. We have the mitochondrion
that has its own unique set of DNA, which over
evolution has come to carry yet another remnant of DNA in every cell. Now, the reason why the
mitochondrial DNA is of use is that it is strictly
maternally inherited and carries a trajectory of
our maternal inheritance. So, these are my two show-and-tell
sources of information. And so, that I don't exclude
the males in the audience, yes, you have that little
thing there, the Y-chromosome. Well, genomic inheritance
is known to all of us. We get half our chromosomes
from each of our parents and they from their parents before, and so on and so on and so on. And so, with respect to mitochondrial DNA, we would be able to check
what both sons and daughters got from mother, from maternal grandmother and great-grandmother, and
so on and so on and so on. In males who have the Y chromosome, we have the equivalent mechanism
to trace paternal heritage but, of course, the nuclear
DNA carries the contributions from both parental sides. And, if you go back one
to three generations, you have eight people who
potentially contribute to your ancestry and, if you
want to go back 20 generations, two to the power 20 would have contributed to your total genomic information but you'll still have a
single maternal ancestor. And it was just by chance
that I chose for my title, So, Where Do We Come From, not knowing that that
is among the questions that CARTA looks at. And the reason I chose that
was about 15 years ago, I was involved in a
documentary that was produced in South Africa by one of the TV networks by the same name and, in
that, we showed a whole bunch of local people
transcending politics, sport and all sorts of disciplines and we did their genetic ancestry tests and made a story out of it. And I was going to show
you some clips from that, but it would have eaten into
my limited time that I had but, in any event, you've
heard about fossils. You've heard about tools. You've seen a little bit about culture and, basically, those
sub-disciplines allow us to check from the past and
build up to the present. The genetic toolkit is the reverse. We study the DNA found in living people and we reconstruct the changes over time. And, for this demonstration,
I'm using mitochondrial DNA, which is only transmitted
through the mother lines to daughters, and only
daughters will pass it on, and the sexy thing about this DNA is that it does not shuffle or recombine. So, you have a mechanism
and a valuable tool to reconstruct the history
of change over time to some point back in the past and, if I were to demonstrate
this with a little bit more of a cartoon. So, if we were to take mitochondrial DNA, we'd be able to link it to
some point back in the past. We call that the most
recent common ancestor for mitochondrial DNA and the
reason why I dislike the use of the terminology Mitochondrial Eve, it gives a sense that the
most recent common ancestor was the only female
present in that time zone, which is not the case. But, in reconstructing the
lineages found in living people, the divergent lines kind of
coalesce or come together at a common point in the distant past dated to between 150
and 200,000 years ago. Now, mitochondrial DNA was made
famous by the seminal paper by Becky Cann, Mark
Stoneking and Allan Wilson where they used mitochondrial
DNA and, in the 80s, we didn't have the
sophisticated technology of polymerase chain reaction
to make lots of copies of DNA from small amounts. These authors went out collected placenta, which was a rich source
of DNA, extracted the DNA, cut it up with little protein tools called restriction enzymes
and created these maps, and what they found was when they looked at the relationships of
all the different patterns that made up the lineages,
one particular branch was exclusively containing
individuals from Africa and, as you went towards the
rest of the tree drawn here as the famous horseshoe-shaped
tree, one found that, in the shallower parts of the tree, individuals from Europe
and Asia were positioned. So, this kind of steer-headed
the Out of Africa theory concerning modern human origins. It wasn't without controversy. There were many, many
site chirps around this, criticizing the technique
for the dating methodology and so on, but that's a long story. But several other types of studies started to come to the fore
and what was now becoming more and more apparent was that, as you went further away from Africa, and for our colleagues from East Africa that's seen as the center of
the evolution of our species, as you went further away from Africa, the amount of genetic diversity was becoming more and more reduced and this was further evidence that our species originated in Africa. I don't think the world
was still ready for this because I mean testing about it, you know, all the social issues going on about coming from Africa, and that's like another
five lectures to go, but I will spare you that. Nonetheless, as the
technology started to improve and we've gone from restriction
mapping to the advent of the introduction of
polymerase chain reaction, better techniques for genetic sequencing and now we can do whole genome sequencing, the culmination of the
human genome project gave us scientists an open
era of asking questions and trying to resolve that
through analysis, et cetera. And so, some colleagues
sequenced a few individuals from the whole genome
sequences from southern Africa, it was the first sequences from
the southern African region, and included among those individuals, there were four people
from Namibia who were San and our famous Archbishop Desmond Tutu. And so, when we got
the results from there, all individuals, with respect
to their mitochondrial DNA, had similar patterns to that
of the San and the Khoi, the indigenous people
from southern Africa, and that is what made the news. Even Oprah Winfrey's show
and all the news bulletins were talking about Archbishop Desmond Tutu being part and parcel of
ancestry to the first people. This was a whole genome sequence. The mitochondria is yet but
a small component of it, but the world was talking about the mitochondrial genetic
study showing linkage of Archbishop Desmond
Tutu to that of the San. Now, what the study brought out was quite an interesting observation. Using the X-axis in a plot of summarizing all of the data collectively, each individual in a pairwise fashion, you saw that there was one
cluster that was associated with African people from the
Niger Congo language family and there was another
cluster that contained those four San individuals and those people from
the European regions. Can you see it, just
casted into like one spot? So, immediately, you can see,
just with a few sequences, the vastness in the
diversity present in Africa and, if you were wanting
a magnified view of that, if you just looked at
the African individual, once again, you saw this
increased diversity. But there's something
emerging from here that people from different parts of the continent, the genetic structure
was seemingly different. And, you know, we had theories
about multi-regional theory concerning all human origins and people started to talk
about, asking the question about evolution in Africa. And so, already, we're
seeing this specific patterns in the southern part, in the western part, and in people who were
migrant to the southern part, similar to that in the
wider part of Africa, namely people who were
speaking Bantu languages. And so, my group has been
for over three decades now, I have been in this business
from the very beginnings when DNA technology kind of hit the world and we picked it up in South Africa, almost like a backlash 10 years later, and so, I came into the
business when we were still using very simple techniques
to the point of where you can do whole genome sequencing now. And, over the years,
through my predecessor, Professor Trevor Jenkins,
we've been interested in the history of peoples of Africa and we have always tried
to do it in a holistic way using genetics as our tool but
also engaging with colleagues from other disciplines,
linguistics, archeology, paleontology, history and anthropology. And so, I'm a bit of an
apprentice of all of that and consider myself more
a molecular anthropologist than a hardcore geneticist
because I'm interested in these sorts of questions. In any event, I had a
very bright PhD student, Carina Schlebusch, who was
interested in following up on some of the studies we
were doing among the Khoi and the San populations. She's now doing amazing work
with Matias Jacobsen in Sweden and, last week, I had the privilege of being at a meeting there in Sweden where they brought
together the world's best working in the disciplines
of linguistics, archeology and genetics to talk about
the diversity in Africa and, while we present a very
simplistic overview here, the more recent work is
actually very dynamic. There are lots and lots of debates and the thing that was most mind-boggling was that there are
researchers in France now modeling linguistics, archeology and genetic data collectively
to kind of get a deeper vision of the past. In any event, we did
some snip chip technology moving away from just
mitochondria and Y-chromosome that we'd been busy with for a while, and what we found was
that the first branch in the human tree with
this kind of genomic data contained populations
that were exclusively Khoi and San speaking peoples. They had genetic information greater than a hundred thousand years and the first time there was a divergence from that major branch was
as recent as 45,000 years ago where we see some splits in populations from Central Africa, Eastern
Africa and West Africa. So, that was quite a major observation. We were not the only ones
who made that observation. Others have done so as well. Now, this is a scary slide, but just allow me to walk you through it. This is another analysis that
people do with genomic data. It's called structure and,
basically, what they're doing is is looking at each individual. So, if we have 500
individuals in our sample, each individual is a data
point across from left to right belonging to that branch
where their sample is placed and it's amount of admixture, okay. So, there are no pure populations. Let's just get that first
fact out of the way. There are no pure populations. People seem to think when
you do admixture mapping, you're starting with two pure populations and then you're blending. No, we are mongrelized ahead of that. And so, now, when you look
across using structure, it identifies this different
genetic backgrounds and all I want for you to see that if you go with the
green being West Africa, the blue, Central Africa and, the red, the Southern African Khoisan, if you look from left to right, you can see different
color structural patterns. And so, this is what
is going on in Africa. There's a deep structure of
genetic patterns of difference across the populations
on the African continent and, if I were to just summarize that by a very, very nice review
written by Carina Schlebusch and Matias Jacobsen published last year, then you would see a summary
of what we've seen before with a difference. What has now happened is by looking at some ancient DNA samples
both in South Africa and in Central Africa in studies published by different authors, they've now pushed that convergence point of dating the common ancestry in Africa
beyond 150 to around 300,000 and that is in keeping with
some of the fossil evidence that's come from Florisbad as well. So, when you now look
at that genetic pattern I presented earlier and you
condense it all together, we see, once again, on one branch, the Khoi and the San populations, Central Africans, West
Africans and East Africans, and a small branch out of that represents what's come out of Africa. So, you can see now why Africa is every expeditioner's paradise because, if you want to
do biomedical research and if you do not understand
what's come out of Africa, you might as well pack your
bags and go to the beach because this is what
you need to understand. And so, we feel very privileged
to be in that region, but it is also quite difficult because, while I may sound
very enthusiastic about it, of course, we have to also
work with all the ethical, legal and social issues
that come with working with human subjects. Now, if I were to just very
quickly summarize graphically in keeping with a map of
where those genetic patterns are seen, you see we also have many gaps. So, scientists are both
busy collecting samples to try to fill up those gaps. And the data is out there, it's just coming into
the public domain now. So, what we see in Africa
is very deep history. What my colleagues ahead of
me have been talking about is that very, very deep history. But how far back do we
take the genetics in Africa is unlike in Europe
where we've got samples from Neanderthals from 45,000 years ago. If some of the archeologists
and paleontologists will allow the scientists to touch
their specimens from Africa, maybe we could go deeper. We did publish a paper two years ago about specimens dating to
just over 2,000 years ago to try to understand what would have been the genetic structure of
individuals pre the migration of people speaking Bantu
languages to the south, and that paper was published, and I didn't want to bring it here, beside it would have taken
20 minutes to explain. So, we have very deep structure. We have migrations
associated with the spread of Bantu languages from West
Africa into southern Africa in the time period spanning
about three to 5,000 years and then we have a very
interesting pattern. With the advent of pastoralism as people started to acquire
cattle and move to the south, the Khoi, who we've sampled in Namibia, carry a genetic pattern, linked
with lactase persistence, the ability to consume cow milk, similar to that found
in the Masai in Kenya. So, this is another very, very
interesting adaptive trait that has come into the
southern part of Africa. Now, for those of you have
been following this literature, you know that people in
Europe have different genetic markers that allow them to process or to consume milk but, in Africa, different genes. So, to the same cultural traits, different genes have been adapted for. And so, in addition to that
sort of tracking of mobility, we've also had input from Europe and Asia into the African continent
at different times. So, not only did Africa
give the rest of the world its genetics, those
individuals who were in exile, some have returned like me. So, a couple years ago,
as I started to engage with colleagues outside of
my discipline to make sense of genetics, I would go
to archeological meetings and engage with other colleagues and it became very apparent
that even among our academics, we were talking across each other. I mean, I would get people calling me up and say, well, if you were to
go to a particular grave site where skeletal remains
were found, can you tell us if those were slaves brought
from Zimbabwe buried there? And so, I would ask, well,
did you think that Zimbabweans had a different genetic
pattern to other Africans? So, we were talking across
understanding each other. And so, I was privileged
to have hosted a conference in South Africa where we invited multidisciplinary colleagues
from within the country and overseas to participate
and I was able to edit a book, one of the first on the
prehistory of Africa, where it was a collection
of bringing together this kind of interdisciplinary dialogue and we've progressed to being able to talk a little bit more now, so much so that all of our genetic studies has
at least an anthropologist or a historian or an anthropologist associated with it. Colleagues, the biggest story is about translation of science. When we sit in our little ivory towers and we communicate just with our peers, we forget that the individuals
that we need to serve are the general public. And so, in my own field
work, having to work outside of the ivory towers of
university boundaries, you really rarely get acculturated into what society is all about
and, fortunately, for me, there's always a tree somewhere and I would use the metaphor of a tree to talk about all living
people being a leaf on the tree and your connection through
branches to the common trunk is actually the history of how your DNA links to the common trunk. It has the opportunity
to bring people together to realize that we are one species, bringing human solidarity
into the dialogue and also having the
ability to tell stories. And so, I created with a company called Jive Media in South
Africa some of these tools where we're telling stories
and, as you tell the story, here the grandmother, the
Go-Go, is telling her family how her people have come
to be where they are. That's oral history. Cultural anthropologists collect
information on oral history and we intertwine the
story into this cartoon where one of the individuals
has been to university and he's had a genetic ancestry test. And so, the young buck,
the curious little guy, wants to know all about it. And so, in unfolding the
story with different cartoons, we now unpack what a
genetic ancestry test is. Now, because that is
what I was interested in, we use it as an opportunity, because lots and lots of people are doing medical research in the
country and that whole issue of informed consent is not
only about the signature, that informed part is
actually very powerful. And so, we try to have tools
to be able to take the jargon out of the conversation
and bring in a visual to help the process. So, I just wanted to
put that little punt in and to say that the science
that we do could not stay out of the public domain. It very quickly crept
in with opportunities to engage the public. People demanded to have
genetic ancestry tests. And so, we had to set it up
and part of that documentary, I even was privileged to have
had the opportunity of testing former President Nelson Mandela and his mitochondrial DNA
was present on this branch. This is my famous tree,
which is actually adapted from the tree that was
published by Behar et al in a schematic way so that we could show how the different branches are related. All the branches with green circles carry mitochondrial lineages
commonly found in Africa and then, as you come out of
Africa, the M branch is seen in the Indian subcontinent
and into the Americas. And through the N, we
see most of the branches that are found in Europe and some in Asia called Eurasian lineages. So, this is a summary of the
mitochondrial DNA patterns that exists in living humans today. So, former President
Nelson Mandela's lineage was found on this branch L-nought, which is the one found most
commonly among Khoi and San and, believe it or not,
having now done research in various communities, one of the things I've tried to do is take back a result, a mitochondria and Y-chromosome
result to individuals so that they don't feel that
parachute type of science that, you know, you go
in, you take the samples and you go back out and
never to be seen again. So, we go back giving them those results. And so, now, some other
unique thing has come about, people are now calling me
up almost on a daily basis to have their genetic ancestry test done because, in some areas, they've been told that if you have your genetic test, it will be your certificate to tell you whether you are San or
not and, in that way, you may be able to claim land in the whole land claim
issue that's going on. So, what started off as
a very complimentary way of keeping the relationship
going between the science and the communities, it's now coming back where there's opportunistic
aspects being brought into it. So, one of the second fact, the first one was that we are not pure populations, the second fact that you must go away with is that a genetic ancestry
test does not tell you anything about your identity. As you sit here, you have
myriads of identities but no genetic test could
define any one of those. So, that's the second thing I
like to emphasize to people, that genetic ancestry is
not equal to identity. Identity is complex, it's
multifaceted and it's fluid. Your genetic ancestry
is the unbiased record of your genetic heritage
going back in time. So, colleagues, genetics,
that was just Genetics 101 or Genetics 0.05, has been
a very, very useful tool to try to track movements
of people around the globe. Not only have we used mitochondrial
DNA and Y-chromosome DNA to kind of plot the final
geography of the human journey, the advent of whole genome sequencing and various types of
analysis with that data now is refining theories
concerning our origins. Ancient DNA has allowed a
deeper view into the past and I don't have time to
talk about those components but it is another way of
gaining insights into questions that we would otherwise not
have had opportunities for. So, in closing, I first
of all want to acknowledge with deep gratitude the CARTA Institute for this opportunity to be here, participants who obviously make us who we are in our careers, various collaborators and funders, and I have to give a punt
wearing the cap of my new role as the executive officer
of the Academy of Science is that science should be done to promote an advanced science,
evidence-based science in serving society. Then there's science for
society and, of course, science for policy. So, the next time you venture
into your science world just try to deposit a few (mumbles) in each of these three boxes. Thank you very much. (audience applauding) - Thank you very much. It's a great privilege to share my opinion on this special topic because,
in the last few years, you might have heard
repeatedly about claims made the earliest of
this, earliest of this, but my discussion is
going to be focusing on the earliest Homo
sapiens claims by people, by different researchers. Assessing claims of the
earliest Homo sapiens needs first to evaluate a
series of recent discoveries and interpretations
that figure prominently in any current understanding
of Pleistocene human evolution. For this, we need to have
the geochronogical position of the fossils securely determined. Whenever somebody says that he has found the earliest Homo sapien, the first thing that we have to see is whether
the dating is properly done. The geochronology is really there. Then after that what you have to do is, according to Lacruz et al, the modern human face is distinct. That means what we have to
do first is we have to define what we are trying to say the
earliest whatever Homo sapien. How do we define Homo sapien? Just to use the recent literature, according to Lacruz et al
(2019), the modern human face is distinct from that of
the earliest hominid species in several important ways
including the following. One, it is relatively small,
the face is relatively small and non-projecting. As you can see it, the
face is very, very small. You know, big head but small face. Second, it shows a depression, what we call the canine fossa. This is the depression. Especially the modern human face has this special depression. Okay, below the orbit. Third thing, I'm trying
to limit my description of Homo sapiens, just
using certain features, and we try to evaluate,
we can use this whole suite of morphology or features but, for the purpose of my
talk, I want to limit it just to the face and small regions. It lacks a pronounced supraorbital torus, what we call the supraorbital
is just eyebrow region. Homo sapiens, like us,
don't have a huge browridge above our eyes. These features do not appear all at once in the fossil record, but
crucial elements are already in place among the
earliest representatives of Homo sapiens lineage. This presentation will
focus on hominid fossils. I'm using hominids just only
for those who are bipedal. My hominid definition does not
include chimps and gorillas. I'm talking only about
the bipedal ones, okay, because the recent
classification use hominin. I'm not using hominin, I'm using hominid. Hominid is bipedal, for me. Okay. This presentation will focus
on those hominid fossils in Africa ranging
between one million years and 150,000 years. The reason why I do that is, one, they have to have good
stratigraphic hygiene. I use a word hygiene
because usually it's a mess. They have to be clean, you have to know exactly
where they came from. This is a word I borrowed
from Miller 2008, which is a very important
word, and the other thing is, a reasonably acceptable age estimate, because the age range
of some of the fossils that we are dealing with these days, they're just enormous. But we prefer a certain age. Sometimes, we prefer, it's
not because that's the age, that is the preferred age, which is scientifically unacceptable. Third, complete enough to make
a morphological observation to assess their taxonomic affinity. So, there are so many fragments of bones, of hominid bones, ranging
between one million years and 150,000 years, but most of them are just bits and pieces. So, to make this assessment,
I really want to use only those who do have mostly face, face included and the other parts. So, when I choose that, there are so few in Africa, very few. I used as base, as a
one-million base level, I use the fossil that my
colleagues and myself found from Middle Awash. Daka because I'm 100% sure
about its stratigraphic hygiene. It is clearly found from
one million years ago based on argon-argon dates and the stratigraphy is clearly labeled. So, with this understanding, between one million and 150,000 years ago within the lineage in Africa,
the African landscape, there were hominids that
evolved from of Homo erectus or whatever you call Homo ergaster. Some people prefer that. There are hominids of the lineage. These different populations of hominids evolved incrementally through time, incrementally through time. That means they add features every time, adding features that lead
towards Homo sapiens. The advanced features
may not be manifested in all populations at once
but Homo sapienization of the lineage has continued through time. So, I see the lineage, it didn't appear, meaning
the Homo sapien package did not appear at once. It is a process, it includes
characters through time. That's what I see in the fossil record. Then my base, the top is what
I used is Homo sapiens idaltu. This is another one which
I am 100% sure about it's stratigraphic hygiene
which is between 150 and 160,000 years boundary
and the age is undisputable. So, the morphology, it has a
clear homo sapien morphology, which we'll go through it later. So, the Homo sapien
lineage may have originated around 500,000 years ago or earlier. So, using their features,
the hominids may be treated in three groups or stages, early, middle and late stage. This is an arbitrary boundary
that I try to break them. The earliest, from the complete ones, which is part of the face, which is the morphological feature that were manifested early in the lineage is from Elandsfontein/Saldanha. The age, between 700 to 400,000
years ago based on fauna. Recent faunal work
suggested older than 600,000 maybe from 600 to one million. Browridge, this is what
we call the browridge, the browridge is very
thick and undifferentiated. Undifferentiated means in
Homo sapiens, the middle part, which we call the superciliary
part is a little bit thick and the lateral part is thin. But in Elandsfontein
or Saldanha, it's thick mediolaterally which is
a very primitive feature. The occipital torus is not strong and that is common to all Africans, even African Homo erectus,
they all have similar kind of, we cannot use it, but what else do we use? The frontal is less constricted. This is the beginning
of Homo sapienization. The frontal part, this
part, is not constricted. In the earlier part, in the
earlier groups, in Homo erectus, this, the lateral part
of the most lateral age of the browridge is very
wide compared to the frontal, but in this Elandsfontein, the frontal is not very constricted. It's even less constricted
even than that of Broken Hill. This feature is more
advanced than Homo erectus. This is a beginning and the
cranial capacity is 1,250 cc. It's much bigger than Homo erectus, much bigger than Homo erectus. That means brain expansion has started. This is a trend going
towards Homo sapiens. Okay, then the associated tools, still Acheulian. That is the kind of tools
that we have been seeing with Homo erectus. Let's go to the next group. This is Bodo. Bodo is skull found in the
middle hours in Middle Awash, in the area that I've been
working in the last 30 years. Age, 600,000 based on argon-argon dating. Cranial capacity is exactly the same as Elandsfontein or Saldanha, 1,250 cc, much bigger than Homo erectus. The Homo erectus is under thousand cc. That means the brain
has started expanding, expanding which is a direction that we see going towards Homo sapiens. High and arched temporal squama. When you see this region, in Homo erectus it forms
almost like a straight line but, in these guys, it forms like an arch. It's an advanced morphology. Supraorbital torus, differentiated, meaning the lateral part is thin and the middle part is thick. This is a kind of morphology
that we see in Homo sapiens. That means they are adding morphology, going towards Homo sapiens. The associated tools are
Acheulian like Homo erectus but the morphology is changing. Unfortunately, the occipital
part is not preserved. What about Broken Hill? Age, unknown. We don't know. Klein, correlated the fauna
of Olduvai Upper Bed II through Bed IV. That age range is between 1.78 to 490,000. You can put it anywhere, so. But the temporal squama
is arched like like Bodo. It's an advanced Homo Sapien kind of Homo sapienization that we see. The upper scale of the
occipital, which is this one, is relative to the lower scale is big. That is also an advanced feature. Frontal is transversally expanded. This is what we call the frontal. Unfortunately, it's still primitive because it don't have a forehead. We have a forehead
which makes us different from Homo erectus but this guy, even though it has big
brain, but no frontal yet, but still transversally expanded It's big, it's a homo
sapienization that we call. A cranial capacity,
it's a little bit bigger than Bodo and Saldanha. Now, you can see the
brain keeps expanding, the other features are not there. What about Ndutu from
Tanzania, from Ndutu bed? Age estimates about 400,000 years old, see discussion in Millard. There are so many
discussions about the age, but the age range is about 400,000 What is important about
this is cranial capacity. And so it is small, may be of a female, because there is a sexual dimorphism between males and females 1,100 cc, looks smaller than Bodo,
Broken Hill and Saldanha, but it has more Homo
sapien features than them. The occipital is not flexed. You can see it from here. It's an open occipitor. In Homo erectus, it is flexed
but this one is really open, especially the back
side is almost vertical. Has a post canine fossa, something that we have never seen before in Bodo, Saldana or Broken
Hill, it is this part. We Homo sapiens have a
depression right here, which we called the post canine fossa. That is a Homo sapien
character at that stage. The associated tools, still Acheulian. So, the brain size is much
more than Homo erectus. The occipital has changed
towards Homo sapiens, vertical occipital, the
upper scale, canine fossa, the most important part is developed and the torus still thick. It shows a little bit of differentiation but still the lateral part is very thick. It's a mosaic evolution
that we see in these groups. What about LH 18, Ngaloba. Again from Tanzania,
from the Ngaloba Beds. The age, Hay (1987)
reported age of the fossil for LH 18 in the marker tuff, probably greater than 128, 29,000 to greater 130,000,
certainly, less than 990,000. Millard (2008) reported
an age less than 490,000. Now, you can see how
(mumbles) the dating is. My assumption is an age of 400,000. This is just an assumption, maybe an age of 400,000 may be acceptable. Cranial capacity, 1367,
its peak cranial capacity. Occipital, you can see
the back of the skull open with no torus. That is also an advanced feature. Post canine fossa is visible
like the one I showed you in Ndutu, it has a post canine fossa which is also present in
modern Homo sapiens like us. Okay, what about Florisbad
from South Africa? Based on ESR dates,
the age's best estimate is 329 to about 189,000 years. See Millard in 2008. Has a canine fossa. Look at this. This depression is
called the canine fossa. Short face typical for Homo sapiens but the earlier forms,
especially, Ngaloba, the face is still big, even
though it has canine fossa. That means everything
did not come together. Everything did not come together. Okay, the frontal is very steep, has developed a steep frontal, a forehead. The anterior surface of
zygomatic forms 90 degrees. This one is 90 degrees. That is typical Homo sapien. What about Jebel Irhod? Long and low cranium,
continuously thick browridge. These are primitive morphologies. Cranial capacity is 1450 cc. That's more than average
even for modern humans. You know? Okay. Convex frontal but still low. Convex frontal still
low, probably just thick mediolaterally which is very primitive. Occipital, moderately angled. Short face. The anterior surface of the
zygomatic forms 90 degrees which is typical Homo sapien. The dates of Jebel Irhod evolved from, some evolution of dates, now you can see, when it was first published it
was 40,000 years old in 1968, then 160,000 in 1991 and 300,000, 2017. This is the evolution of dates. I'll suggest to read it
other sites like Florisbad and others for whatever words it may be. The dates they may also
evolve in that direction. What about Omo, the Omo Kibish skulls? There are two different kinds of skull. This is Omo one and this one is Omo two. Omo one is very advanced,
typical Homo sapien. Steep frontal, (mumbles)
morphology, very Homo sapien like. Omo two is very archaic in
occipital and frontal profile. They may not belong to the same group of evolutionary status. Omo two is less advanced and may belong to ancestral lineage of Omo one. It may belong to a different
contemporary populations. It may. If they are from the same horizon. Based on taphonomic evidence, they may not be contemporaneous, even though they are published
as to be as contemporaneous, for interpretation, it's misleading. If we can confirm it,
it's an evidence by itself for two different populations,
one advanced population, the other primitive population,
to live side by side but, based on our observation, Omo two is very, very primitive. You can see it's an isolated surface find, no associated archeology like Omo one. Cranium is long and massive, very low. You can see that the frontal is very flat and the occipital is very
flexed unlike Omo one. Frontal is low, weakly keeled. Strongly angled occipitor. Cranial capacity's very big, typical Homo sapien type. Broad and constricted frontal. Parietal is bulged and expanded. And it was a surface find,
not associated stone tools. So, we think based on this
evidence that we observed on the fossil, not the
polished, eroded supraorbitals. They are polished and
eroded and the polish is also on the temporal surface. They are highly polished. So, these features may suggest
hydraulic transportation of the skull by paleo Omo
river or its tributaries. So, I think they are not contemporaries and this is a very good information to take into consideration. Herto, let's see. Small face tacked under the brain case. Small face tacked under the brain case. No projecting mid-face. The mid-face not projecting. It's only the lower part of the face looks a little bit projections, it's a very, you know, kind
of primitive character. Anterior surface of the zygomatic, this area forms a vertical orientation. This vertical orientation
typical Homo Sapien. Has a post canine fossa. That is something I've
seen in Ndutu and Florisbad and Jebel Irhod. Okay, inferior border of
zygomatic joins 90 degrees, typical of Homo sapien. A steep frontal, that is
major mark of Homo sapiens, steep frontal. Browridge differentiated
into medial and lateral. The lateral part is thin and
the medial part is thick, typical Homo sapien. Occipital is open and flexed. Long vault but still has
some primitive characters. So, what do we learn from the Middle Pleistocene
fossil record in Africa? The Homo sapien lineage emerged early, maybe by 500,000 years
ago and earlier groups, between 500,000 and one million years ago, Daka and Buya, between
those times may represent the last common ancestor
with the Neanderthals. The change observed through time includes brain expansion that we have seen from Saldanha time, parietal bulging, as we observed also Saldanha time, occipital less flexed. That is that we have seen
in at least by Broken Hill. Facial profile, advanced and small. And smaller, that is what
we see next by Ndutu time. Brain getting bigger and
frontal keeps convex, but still low. That is what we see in Jebel Irhoud. Browridge reducing, occipital more open. A steep frontal, smaller
face, that is the third stage that we have seen. This is what we see in Ndutu and still with some primitive features. Then when we go, the first
stage, there is one stage, that's a brain expansion
that we have started in the earlier parts,
and the second stage, then we have seen a little
bit of facial change like the first emergence
of the facial morphology developing post canine fossa. And the third stage, superior expansion and lateral part of
the browridge thinning. This is the sequence that
we have seen through time. Then at which stage of
the lineage do we claim the earliest Homo sapien
status for a hominid? It's unfortunate we use that terminology and I think it is misleading. So, it is an arbitrary term
that we use the earliest and the easiest thing to do is we find a Homo sapien at 160,000. We find a Homo sapien at 400,000 but the earliest is a
misleading terminology, I think. I thank you very much. (audience applauding) (pleasant music)
