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Note: This document is from the archive of the Africa Policy E-Journal, published
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Africa: Common Ancestors
Africa: Common Ancestors
Date distributed (ymd): 020425
Document reposted by Africa Action
Africa Policy Electronic Distribution List: an information
service provided by AFRICA ACTION (incorporating the Africa
Policy Information Center, The Africa Fund, and the American
Committee on Africa). Find more information for action for
Africa at http://www.africaaction.org
+++++++++++++++++++++Document Profile+++++++++++++++++++++
Region: Continent-Wide
SUMMARY CONTENTS:
While most of our postings relate to immediate policy issues, we
also sometimes feature articles which deal with the broader
cultural and social context, part of the background environment for
policy debates. In the current context, it is of critical
importance whether or not citizens and policymakers accept that we
are all part of a common humanity. This interview about a new
documentary video, reposted with permission from allAfrica.com,
deals with scientific debates that range far into the remote past.
But the issues raised about how we conceive our common humanity are
also critical to the future.
News releases from the Discovery Channel on the program are
available at:
http://dsc.discovery.com/news/briefs/20020225/eve.html and
http://allafrica.com/stories/200204190697.html
The Discovery Channel also has other related feature material on
their web site at:
http://dsc.discovery.com/convergence/realeve/realeve.html
A site with links to other sources on the origins of humankind is
http://www.versiontech.com/origins
+++++++++++++++++end profile++++++++++++++++++++++++++++++
Common Ancestor, One African "Eve" for All World's People
Portrayed
allAfrica.com
INTERVIEW
April 19, 2002
By Charles Cobb Jr. Washington, DC
In a television documentary [aired on the Discovery Channel on
April 21], humankind is said to share a common genetic link that
can be traced to one woman who lived in Africa more than 150,000
years ago. Using a unique part of human DNA called mitochondrial
DNA" which is passed from mother to daughter, "The Real Eve",
narrated by actor Danny Glover, tracks the movement of humanity
from this common ancestor across geography and millennia.
AllAfrica's Charles Cobb Jr. spoke with the film's producer, Paul
Ashton. Excerpts:
Cobb: We should start with the science and the point the film is
trying to make. Can you explain this in layman's terms? DNA? The
"real" Eve?
Ashton: The point of the film is to tell a story about the
movement of people, where we came from and how we got to where we
are now. And the new genetics are able to tell us how we got to
where we've got now. And where we moved to and through. So
Mitochondrial DNA, which is the maternal line carried by everyone
- its the DNA of the mitochondria - becomes key. Mitochondria are
like little batteries that energize everybodys' cells. They have
their own DNA which you can trace. Men cannot pass it on, only
women. The mitochondrial drops off the sperm as it enters the
egg. Every so often there is a very small harmless mutation which
doesn't effect anything other than that scientists can read it;
they can see the mutation. Basically they can see which mutation
came first. So every mutation is layered on the previous one.
It's always passed on exactly as it is. And where there is a
split in the mutation you can tell that is where populations must
have split. If somebody carries the same mutation up to a certain
point along with another population and then suddenly they are
carrying a new mutation which that other population no longer
carries you know that group must have left before that second
mutation.
Cobb: And these mutations would be what? Color? Hair? Body
features?
Ashton: No. Nothing to do with us. Mutation is a word that always
conjures up that sort of thing but it's actually a marker. It has
no effect whatsoever because it's within the midochondria. And
it's just something that we can see but it has no effect. It has
no relation to our color or height or our eyes or anything like
that at all.
Cobb: Okay. This sounds like interesting science, but a film?
What in this science leads you to a film?
Ashton: Well, the film is about our human journey. Everybody on
the planet carries the midochondrial DNA of one woman who lived
150 thousand years ago in Africa.
Cobb: Where in Africa?
Ashton: We think in East Africa. Archaeologically we know that.
You can't tell that from genetics. Archaeologically we know
pretty well that we came from the southern end of the great Rift
Valley. Also, the genetic markers around that area are numerous
too, so that's the most likely place that we arise from as well.
I do have to tell you that although I am telling this story, the
reason I am able to tell this story is because I have done a lot
of work on it over there last two years, but I am not a
scientist. There is no way that I can explain all of the
technical, academic details. So basically we know that we all
carry the genetic marker of one woman who lived over 150,000
years ago in Africa, but then we talk about how did human beings
first leave Africa and where did they go to then. Well, because
of the genetic tracing we know that everybody outside Africa
carries a mitochondrial marker of one woman who must have been in
a group of people who left Africa about 80,000 years ago. And we
know that group was a group of anything from about 250 to 700
people. We think it's about 250. Less than 250 wouldn't have been
able to sustain a population and much more than 500 or 600 people
would have taken too long for it to drift down to one line
because they have to stay together. We also know that it was one
group that left once. It wasn't a stream of people. It wasn't
lots of groups leaving at different times. It had to be one group
once because it all comes down to one line. For example, if you
take a small remote Italian village you will find that a lot of
the people in the village carry the same name. That's over time,
because some people just have daughters. You drift down to one
name. In same way you drift down from one line. So there might
have been lots of lines coming out of Africa in this one group
but because they stayed together sufficiently long enough they
all drifted down to one line.
Cobb: Which you can tell from the genetic marker?
Ashton: That's right. That line then became the "mother", if you
like, of everybody outside Africa. And then they started to split
off. Some went down to Australia; some went up into Central Asia;
some went up into Europe - carrying their own markers from that
point. So it's rather like the branches of a tree with the main
trunk of the branch being in Africa.
Cobb: And the film shows this? Documents this?
Ashton: It trys to tell the story in a dramatic way because we
want people to understand the science but we also want people who
aren't particularly turned on by science to also be able to enjoy
the film on an entertaining level and be involved in the story of
"us." We want people to be able to look at the screen wherever
they are, whoever they are - whatever color they are, whatever
creed they come from - to look at that screen and say this is our
story. It's not these strange people who lived thousands of years
ago. This is a story of our forebears.
Cobb: Do you have a favorite part of the film, or a part that you
consider especially important in the sense of what you want to
convey to the viewer?
Ashton: The part of the film that moves me most is the death of
the little boy when he falls over and his father carries him and
buries him. He died 44,000 years ago. From his skeleton we
recreate that scene. It shows a caring side of humanity. This
little boy was obviously damaged because he has a broken skull
and he was laid very carefully in this recess a cave and was
obviously buried with care and love and I think that a parent's
love for a child is what really the human race is about. And the
only problem is, is that we don't seem to be able to care that
much about "other" people's children.
Cobb: You've said that you're not a scientist, and certainly not
a specialist in this area, so how did you, the filmmaker,
encounter this piece of science? How did you get engaged?
Ashton: I read a book written by professor Stephen Oppenheimer
who is the professor in this film. We are telling his synthesis.
He's the man who came up with the scientific end of this. I was
talking with him about this other book he had written with the
view of trying to make a film out of it and he told me this story
that everybody outside of Africa comes from one small group and
that everybody on the planet is related to one woman. And I
thought that was just an extraordinary thing. And I said this
would make a beautiful film, a lyrical film, which is what I
wanted to do.
Cobb: Let me ask you again, getting back to the actual story, Why
did this group of people leave in the first place? And where did
they go?
Ashton: Obviously that's conjecture, but we believe that they
were beach combing. And we have proof of modern humans beach
combing along that particular coast of Africa about 80,000 years
ago. At that particular time there was a major freeze up of the
world and the world became much drier. And also because of the
shallowness of the Red Sea that would have become very, very
salty. So whatever they were eating while they were beach combing
would have been dying off. Just across the water from where they
were you have Yemen, which was at the time was being hit by some
freak monsoon weather and it was very green and also it was on
the ocean side, so the water wouldn't have been so salty. It must
have looked very tempting for them. Such a short distance away,
green inviting hills. They were standing on this rather deserted
desert lacking food. That's why we think they made this trek
across the water.
Cobb: And then from Yemen they go North, South...where?
Ashton: From Yemen they went to the Gulf of Arabia which at the
time was dry because sea levels were so much lower. The gulf was
actually fresh water lakes; it wasn't the gulf as we know it
today. So it was a very good place for them to stop. Some of them
went all the way round the coast all the way down to Australia
and then all the way up the coast to China. Some of them went
North of the Himalayas into Central Asia. Some 30,000 years after
they got to the Gulf, they then went North into Europe because
the weather changed again, opening up a green corridor from where
they were in the Gulf up into Turkey. There was some wet weather
that greened the desert. this is why they didn't get into Europe
until 50,000 years ago.
Cobb: This charting of the routes seems pretty precise.
Ashton: Yes it is pretty precise. If you're carrying a marker -
up to a certain point if a population is carrying a marker up to
a certain point - and then beyond that point that marker isn't
there you know which direction the people are moving. So you can
say, well at this point there must have been a split because the
marker then goes over there and the new marker happens over here.
It's a split in the branch; you have two more twigs.
This is what was so wonderful about the end of the film. You had
two people from opposite ends of the world carrying the same
marker. There was a Greek lady, Angela, who was a recent
immigrant into America from Europe. And then there was a native
American who was a full-blooded Cree. And we tested them and we
found that they both carried quite a rare marker in their
mitochondrial DNA which is called "X" for no other reason than
that's the letter that the scientists gave it. Now "X" first came
into being in Central Asia about 30,000 years ago. So what it
means is, that one of the daughters of our out of Africa "Eve"
had a mutation that we call "X". Her familiy then split. Part of
her family went West towards Europe and part of her family went
East toward Siberia and then on into America and became the
Native Americans. So when Angela came to the United States from
Europe and she met with Leonard in our laboratory it meant two
members of the family were rejoined 30,000 years later.
Leonard was completely blown away. But it doesn't change the fact
that he is Native American. He can still be part of the first
people of North America. We're going back 30,000 years and we
know that human beings didn't get into North America until about
20,000 years ago so his family could have been part of that first
group. What it does do is prove that we all come from the same
place, that we're all brothers and sisters. We really are, not
just in a moral sense, but actually in a physical sense. People
better get used to the idea.
Cobb: It's important to understand that this is taking place over
thousands of years....
Ashton: Thousands of years. You're not talking about a couple of
generations; you're talking about 5,000 generations.
Cobb: And I assume that in addition to moving they are changing
in the sense of physical characteristics in order to adapt to
various climates that they find themselves in, and I suppose
developing languages as well
Ashton: Yes, they are changing. Absolutely correct although they
might well have had language before. In fact we know that they
did because they possessed the hyoid bone which is a bone in the
throat which enables us to talk. We know that Neanderthals and
homo Erectus and early hominids had the hyoid bone so we know
that they talked as well. So we had speech.
Cobb: But we're not talking about primitive people here. This is
modern man.
Ashton: This is modern man! One hundred and fifty thousand years
ago this woman who was our genetic "Eve", if you like, had all
the capabilities that we have today. And all the potential. She
was just like us! If we were to bring her to this time, educate
her, dress her up and walk her down the street you would not know
the difference. We are not talking about primitive early people
who dragged their knuckles on the ground!
Cobb: Is this "new" in the sense of science? Is this a
breakthrough or has this been around?
Ashton: That aspect of it isn't new. The early Mitochondrial Eve
"mother" is not new. That has been around in scientific circles.
But what is new is the out of Africa group that left once; the
way they left which was the southern route across the mouth of
the Red Sea, and also the movement from the Gulf into Europe
50,000 years ago. That is all brand new.
Cobb: Is it controversial?
Ashton: It is controversial. But only because some people don't
like other people to get things right. But people are very very
quickly coming to realize that this is something they can no
longer argue with. Professor Stephen Oppenheimer, whose synthesis
we filmed, was the first person to come up with these aspects
because he looked at all the information, not just the genetic
information. He looked at the oceanography, at the climate; he
looked at all the things that were happening and came up with
these explanations which have now been argued about for a little
while but have held up.
This material is being reposted for wider distribution by
Africa Action (incorporating the Africa Policy Information
Center, The Africa Fund, and the American Committee on Africa).
Africa Action's information services provide accessible
information and analysis in order to promote U.S. and
international policies toward Africa that advance economic,
political and social justice and the full spectrum of human
rights.
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