Here are
Papua New Guinea, Bougainville Island, which is right next to New Guinea,
here are the non-African Homo sapiens and here are the African Homo sapiens.
So, here are the African, Homo sapiens, non-African Homo sapiens and this is a
multi-dimensional figure that says, to what species are the Denisovans,
these, these neanderthals out there, are most closely related?
Well, they seem to be more closely related to those people
who move down into Southeast Asia, deep into Southeast
Asia, with the Denisovans. And what people think was
that here are the normal neanderthals, and
they exchanged, there, there are a few incidences of gene exchange but no
major interbreeding at all and then the Denisovans are
sharing some features with Melanesians. But it's a
bigger story than that, and let, in here, in this complicated diagram,
we're picking out only one gene, the exon
44, the dystrophin gene. And we're looking at all the variants.
So all of these little lines here are variants,
haplotypes, of that gene. Neanderthals have
a cytosine right there in position one
and they have a guanine right here in position 31.
And there is a haplotype B006 that also shares that
neanderthal gene but also, it also shares this uniquely
with, with neanderthals. Now where is this haplotype found?
It's all over the world.
Virtually all people, other than Africans, have, have that.
It's been very, it's, it's found in many, many populations around the world.
Because Africans, of course, were isolated from the neanderthals and all
that movement of Homo sapiens, so they didn't pick of this gene.
But what people think is that at some time in the past,
as Homo sapiens were moving across Southern Asia,
some of them got up into a lower
part of Siberia and interacted with Denisovan neanderthals.
And there must have been some in, instances
of breeding and they picked up these markers.
Now this is not the only marker in Homo sapiens that
indicates that very isolated interbreeding but in a,
in a sense, all of us can, many of us can
go around and we can say, I'm also a little bit Neanderthal.
So as, wave after wave, there were many waves that came across here, and
the, some of them came up in here and they interacted with the Denisovans.
This is a, on the left hand side, this is a phylogenetic tree or a gene tree,
really, for a huge, huge number of Homo sapiens, modern humans.
And, the idea, the objective of this gene analysis is to try to understand how
people move into Asia and into Southeast
Asia and, eventually, moved over into North America.
It was a very complicated pattern.
Populations came into India, they moved over into
Southeast Asia and then they moved over out into Northeastern Siberia.
They moved down into the Malaysian region, in other words, the Philippine region.
Melanesians came down and, and got into Australia and New Guinea and then,
other groups came down this way and then moved out across the
Pacific because we now understand that the Polynesians
have some genetic connection with populations that are up
here in Southeast Asia and not with, not with Melanesians.
At the same time all this was happening, humans moved across the Bering region.
Now the, this is the Bering Sea but at various times that was exposed so
they must have come in at, at a time when there was the glaciations.
But there was, we now know that there was
a corridor either through the middle of the ice
sheets or along the coast and people prefer this
because we have a lot of archaeological evidence out in