What ancient DNA can teach us about migration in prehistory | Professor Ian Barnes | TEDxLondon
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What ancient DNA can teach us about migration in prehistory | Professor Ian Barnes | TEDxLondon


Translator: Behdad Khazaeli
Reviewer: Hélène Vernet Hello everyone. So, I’m going to talk today
about migration and movement, and particularly people moving
into the British Isles in the past. And if we think about
past migrations into Britain, we probably first off might have
some ideas about the 20th century, people coming from the Caribbean,
from east Africa, or from India, or Pakistan,
or places like that. And if we have to go back
a bit further in time, of course we’ve got people like
the Normans, Romans or the Vikings. But despite the fact that we’ve
noticed quite a lot of people who have moved
into Britain at different times, I don’t think we really
think of ourselves as a migrant nation. We think of ourselves
more outside as an island nation. But what about if we go back
really a long way, we really go back far in time
beyond the time when there is any notion
of a Britain or an England, beyond any kind of english language, in fact beyond written history at all. In fact, we can go so far back in time that Britain is actually
not even an island at all. It’s still joined to the continent,
still part of the Eurasian landmass. So that’s what I want
to talk to you about today, about Britain in prehistory,
and the prehistory of migration here. So we’re going to take
a big jump back in time, but I can’t do that
with you all in one go. So we are going
to take little jumps first. We are going to jump back
to the late Victorian period, and we’re going to start off here. Here, we start
in Somerset at Cheddar Gorge. It is here during the last decades
of the 19th century, that this guy, Richard Cox Gough, discovered and excavated and blasted out a series of caves that he made into
a major tourist attraction or a showcase. But it’s actually a year
after Richard died that the really big discovery was made, the one we’re actually interested in. So that discovery was made
in December, 1903, and it was made by Richard’s son, Arthur,
who was digging a drainage ditch to try to combat the seasonal flooding
that they had in the caves. They tended to make
all their big discoveries in the winter because that’s when
there weren’t any tourists around. So workmen who were working on the cave actually blasted out and uncovered the skeleton of an adult male. And rather quickly,
this skeleton made big news. Experts of the day said that perhaps
it was the body of the first Englishman, and that he was of extreme importance, that he was at least 40,000 years old and perhaps as much as 80,000 years old. Well, that’s not entirely true. What we actually know today
is that “Cheddar Man,” as he became known, Is actually about 10,000 years old, but he is still certainly very important. He’s extremely important
for a number of reasons. Firstly because he is the only
near-complete skeleton that we have from
that kind of time period. He is also important
because he’s the only one where we have a complete skull
or near-complete skull. And here is the skull,
in this rather post-setting with the two brothers,
William and Arthur, staring at it. They seem to be enjoying themselves which is what I really like
about this picture. (Laughter) So what else do we know
about Cheddar Man? Well, he’s definitely a man. And that has been the subject
of a little bit debate over the years because he has a rather
gracile and slender skeleton. He was probably
in his early twenties when he died; he was buried deliberately, it seems, and he was buried on his own. Today, he looks something like this. This guy has been better assembled, and you can see him
at the Natural History Museum. He is on display a couple of galleries
away from where my office is. So, we’ve worked on Cheddar Man and a number of other
individuals over the years and built together
quite a large complex project exploring the history
of the British Isles. And one of the things that came up
as the result of that project was the opportunity to take part
in a channel 4 documentary where we were going to explore
Cheddar Man and his history to build up more of a story about him. So that was good because we already
had quite a lengthy project working on the history
of the British Isles, but what the people
who put the documentary together wanted to know about was something a little bit
more complicated, more detailed, and that was about his appearance, about his skin color,
hair color and eye color. And what we were able to do
for them was to supply that information. We passed it on to the people
who made the reconstruction. Well, they came back with this, an individual with a rather small face
compared to the overall size of his head, with blue eyes, dark curly hair, and obviously with dark skin. And that was a surprise for some people, for most of the people
I talked to actually. And most of them actually seem
to think that this was rather cool. People who saw the show
generally quite enjoyed it. We weren’t particularly surprised by this because similar information
had already been generated by a group, a couple of year previously, looking at different skeletons
around Europe of a similar kind of age. They had already identified that dark skin was practically normal for people
about 10,000 years ago. But what we’ve been able to do was better quantify
exactly how dark that was. And we’ve done that using a tool
borrowed from forensic sciences. Some people didn’t think
that this was very cool. Some people I think were expecting to see
something a little bit more like this, which is the results
of the previous reconstruction. Both reconstructions
are obviously quite different, but they do share one feature at least which is this rather wispy facial hair. And I’m surprised about that because
there’s really no evidences either way, from the archeological genetic data,
that would tend to actually suggest that. But that is perhaps
their only shared feature actually. So those people, who didn’t
think it was very cool, were a bit surprised, and they made their surprise
known on social media, as you might expect. And actually things got rather heated
there, and you can look at that. Right now I don’t really want
to go into too much detail about it. But here’s one of the sort of slightly odd
events that happened there, one of my childhood heroes indirectly … (Laughter) … indirectly congratulating me
on having upset some people. So that was a little bit weird actually. And that went on for a while. So, what became clear to us
was something rather disappointing. As I’ve already said to you,
we had spent quite a bit of time getting a pretty good understanding of what the population history
of British Isles actually looks like. So how do you get from someone like this
to people in the audience today? I mean Cheddar Man
obviously not Billy Bragg! So that’s what I’m going
to go through now, what we’re going to have a look at. Okay, but before we can do that we have to work out how exactly
we’re going to look at that information. We really have a lot of data here. The human genome
has 3.2 billion base pairs and I can’t just keep flashing that up because we’d run
out of time quite quickly. So what we need to do is find a way
of crunching those data down and just pulling out the most important
and interesting parts of it. And the method that we often use
just to get a handle on the data initially is called the “principal
components analysis,” and that’s what I’m going
to show you here. So these are genome data that has
been squashed down onto something that looks a bit like a graph or a plot. And so individuals who are close together
are genetically similar to each other, regardless of where
they might happen to come from. So let’s start here with Cheddar Man. But all alone, like he was
in Gough’s cave, he’s not actually doing much for us,
he’s not telling us very much. So let’s put on the other five
individuals from Britain, from which we have very small amounts
of genome sequenced data, and see what happens. What happens then is that they all
plot together quite neatly. Despite the fact that we have
individuals here from Scotland, Wales and southwest England, they actually all look
quite similar to each other. Let’s expand the search a bit more
across the rest of Europe. What we have here
are some more individuals. The ones in blue are older individuals, slightly older ones
from slightly earlier time periods. The ones in that kind
of dark red color are of a similar age. And these are samples that have been taken from Spain, Hungary, Germany, Sweden, Luxembourg,
all sorts of places including Britain. And what you see is that the British ones kind of bridge the gap
between the earlier and later ones. But there’s still not much
of a picture here. Where we do get a bit of a surprise
is if we jump forward in time a bit more. Okay, so what we have here, about 4000 years after Cheddar Man died, is that something quite
surprising happened in Britain, and that’s the origins of farming. So the first farmers had arrived
in Europe several thousands years earlier. They had arrived in Greece. They are the red folks on that plot. They’d made they way across Europe
over several millennia and eventually arrived in Britain where we have the grey
individuals on the plot. What you can see there
about those grey people is that we have two important
things to get out of this. They are genetically extremely different to the hunter-gatherers
that were in Britain at that time. And they entirely replaced them, a complete replacement of the population. Now it’s always tempting at these points
to think of some kind of vast horde arriving and committing
some kind of genocidal act on the people, the peaceful
hunter-gatherer people. We don’t have any evidence
for that at all. So what we think in fact
is quite plausible is that there were actually
remarkably few people in the British Isles at this time. [Farmers] arrive and just take over. And they can easily take over the country. What is even more surprising is that a very similar thing
happens about 1300 years later. A second genetically very distinct
group arrives in the British Isles. These are the so-called “Beaker people”
who are called that because of the distinctive ceramic vessels
that they’re often buried with. These Beaker people
were also genetically very different and seem to completely replace
the Neolithic people there, the farmers that were there before. And this, it seems, is the last major population
replacement that we can detect at the resolution that we can work with
at the moment, with ancient DNA data. So if we bring up now
the modern population across Europe, you can see that those
Beaker people sit pretty much on top of current
British Isles populations and, in fact, the populations
of northwestern Europe continents in a bit of smear across there as well. Okay, so what can we draw from this? What do we really have to conclude here? One of the things that I realized some time after we’ve done this work
and the documentary show was that for some people who are upset by the way we had
reconstructed Cheddar Man, the issue was one
of population continuity. We had challenged
that notion that they had that there was a long-term
population continuity in Britain. And that’s very much not
what the data seem to be saying. The history and the prehistory of Britain is one where populations
are under a series of replacements. The other thing that you can
also draw from this data is about migration and our modern day
concerns about mass migration and how it affects society. What you can see here
is that the scale of migration today, despite the advent of globalization
and mass transportation, is nothing like the kind of migrations
that we must have had in the past that have led to these
very large-scale replacements. Thanks very much. (Applause)

21 thoughts on “What ancient DNA can teach us about migration in prehistory | Professor Ian Barnes | TEDxLondon

  1. The final statement is ridiculous: "The large scale migrations of today are nothing like the population replacements of the past." You're comparing ten thousand years with the past three years since the 2015 migration tsunami? Do the math. If current trends continue, you're looking at mere decades for major population replacement. Forget about centuries. And definitely it will not take thousands of years.

  2. I think its pretty cool that the whg had such an interesting physical makeup. I don't think its cool when people try to hijack this fact for some obscure political agenda.

  3. Another ultra-liberal Globalist .
    Another supposed intellectual funded by government taxation .
    Taxation contributed by them that do some actual physical work
    by which these parasites depend on for sustenance .

  4. So the entire point of his talk is that it's okay for Muslims to move in? And based on that we have a great future? Another white guy living in the world of denial deceit and delusion.

  5. They weren't complete replacements. Neolithic Farmers from the Near East replaced around 90% of the hunter gatherer population. Later the Beaker People who had a strong genetic contribution from Yamnaya pastoralists from the steppe replaced around 90% of the Neolithic Farmers. So he's wrong when he says they completely replaced the previous people. There was a high degree of of population replacement, but not complete replacement.

    The other important fact he leaves out is that both the neolithic farmers and steppe pastoralists were already admixed populations themselves and they became more mixed by the time they reached the British Isles. The neolithic farmers had western hunter gatherer admixture and the original Yamnaya steppe pastoralists were a mix of eastern hunter gatherers and Neolithic Iranian Farmers. By the time the steppe people had migrated to become the Beaker People in Western Europe they had already mixed with Neolithic Farmers and Western Hunter Gatherers to some degree.

    It's all somewhat more complex than this, but I'm trying to simplify it to be more easily understood. The end result is that modern day people of the British Isles still have significant genetic contribution from Western Hunter Gatherers, Neolithic Farmers from the Near East, Eastern Hunter Gatherers (including the Ancient North Eurasian component), and Neolithic Iranian Farmers.

  6. Such BS. How can you just look at the recent past in Europe and pretend to talk about the world? People lived worked – baking, aquaculture, etc. – for 120,000 years in southeast Australia. Land masses have changed shape in the intervening years. Not sure how a euro-centric perspective helps in discussions of world migrations.

  7. The history shows that populations can be replaced totally. That migration waves replaced the " indeginous" people.
    He didn't mension mixed with the "indeginous" people or blended in with the "ïndeginous people" .
    The conclusion can also be : migration can be very hazardous for the current "native" population.

  8. He is DEAD WRONG in calling it a replacement.

    Anyone who has done a DNA test with any company can upload their data for free at GEDMatch and find out the % of these old population that make him or her up.

  9. 0:51. He says Britain is a migrant nation here. 12:17. Then he says there has been no genetic change in Britain in the last 4,000 years. Four thousand years is a long time., British people are not a migrant nation. Its history is not the history of constant immigration/migrations from continental Europe into Britain. There were a few population replacements in its early history but for the last four thousend years there has not been a lot of change. Certainly not in the last 1,000 years. Anybody, who knows about ancient DNA or British history knows this. This is not based on politics this is based on plain facts. Trust, me, in upcoming years Ideologies, are going to try to twist the facts of European history to try to convince Europeans they have no legitimate identity or heritage. Its coming. History academia in universities today is dominated by ideologies whose main goal is to degrade and destroy Western identity and sense of history.

  10. I've noticed a clear trend in history books when the topic of ethnicity comes up. Whether it be ancient Greeks, English, Germans, Persians, etc. They always say ethnicity is about culture not shared ancestry. Even though almost every ethnic group in recorded history has defined itself as people with shared ancestry. They do this because of ideology not fact. Because, they don't want an unbreakable bond (common ancestry) to legitimize linkage between people. It is one of many manifestations of the social constructionist. They want everything about reality to interpretation and able to be shaped in whatever way leftist desire it to be. They don't like nations, nationalism, ethnic groups. So, they want people to believe those things are defined only by social constructions not shared ancestry. British are not a "nation of immigrants or migrants." They have shared ancestry with each other

  11. Another political BBC disinformation campain. The truth of the matter is
    different, climate was different with colder winters and hotter
    summers. tribal coast dwellers traded across the ocean possibly
    scandinavia or spain, this was ONE dna sample which could have been an
    invader, trader, or captured fugative who hide out in the caves. Clealy
    to established a scientific trend you will need at least 40 samples. You
    do not have that information. It is likely to be a alien invader who
    traded or tried to invade indigionous peoples in the nearby summerset
    levels.

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