A family tree for humanity
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0:00 - 0:09Jambo, bonjour, zdravstvujtye, dayo: these are a few of the languages
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0:09 - 0:13that I've spoken little bits of over the course of the last six weeks,
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0:13 - 0:18as I've been to 17 countries I think I'm up to, on this crazy tour I've been doing,
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0:18 - 0:21checking out various aspects of the project that we're doing.
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0:21 - 0:23And I'm going to tell you a little bit about later on.
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0:23 - 0:26And visiting some pretty incredible places,
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0:26 - 0:32places like Mongolia, Cambodia, New Guinea, South Africa, Tanzania twice --
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0:32 - 0:34I was here a month ago.
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0:34 - 0:39And the opportunity to make a whirlwind tour of the world like that
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0:39 - 0:42is utterly amazing, for lots of reasons.
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0:42 - 0:44You see some incredible stuff.
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0:44 - 0:46And you get to make these spot comparisons
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0:46 - 0:48between people all around the globe.
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0:48 - 0:50And the thing that you really take away from that,
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0:50 - 0:53the kind of surface thing that you take away from it,
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0:53 - 0:57is not that we're all one, although I'm going to tell you about that,
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0:57 - 0:59but rather how different we are.
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0:59 - 1:02There is so much diversity around the globe.
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1:02 - 1:056,000 different languages spoken by six and a half billion people,
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1:05 - 1:08all different colors, shapes, sizes.
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1:08 - 1:11You walk down the street in any big city, you travel like that,
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1:11 - 1:15and you are amazed at the diversity in the human species.
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1:15 - 1:18How do we explain that diversity?
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1:18 - 1:20Well, that's what I'm going to talk about today,
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1:20 - 1:22is how we're using the tools of genetics,
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1:22 - 1:28population genetics in particular, to tell us how we generated this diversity,
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1:28 - 1:30and how long it took.
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1:30 - 1:32Now, the problem of human diversity,
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1:32 - 1:34like all big scientific questions --
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1:34 - 1:36how do you explain something like that --
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1:36 - 1:38can be broken down into sub-questions.
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1:38 - 1:41And you can ferret away at those little sub-questions.
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1:41 - 1:43First one is really a question of origins.
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1:43 - 1:45Do we all share a common origin, in fact?
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1:45 - 1:48And given that we do -- and that's the assumption
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1:48 - 1:51everybody, I think, in this room would make -- when was that?
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1:51 - 1:53When did we originate as a species?
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1:53 - 1:55How long have we been divergent from each other?
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1:55 - 1:59And the second question is related, but slightly different.
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1:59 - 2:01If we do spring from a common source,
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2:01 - 2:03how did we come to occupy every corner of the globe,
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2:03 - 2:05and in the process generate all of this diversity,
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2:05 - 2:08the different ways of life, the different appearances,
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2:08 - 2:10the different languages around the world?
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2:10 - 2:13Well, the question of origins, as with so many other questions in biology,
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2:13 - 2:15seems to have been answered by Darwin over a century ago.
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2:15 - 2:17In "The Descent of Man," he wrote,
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2:17 - 2:19"In each great region of the world, the living mammals
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2:19 - 2:22are closely related to the extinct species of the same region.
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2:22 - 2:25It's therefore probable that Africa was formerly inhabited by extinct apes
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2:25 - 2:28closely allied to the gorilla and chimpanzee,
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2:28 - 2:31and as these two species are now man's nearest allies,
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2:31 - 2:33it's somewhat more probable that our early progenitors
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2:33 - 2:35lived on the African continent than elsewhere."
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2:35 - 2:39So we're done, we can go home -- finished the origin question.
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2:39 - 2:43Well, not quite. Because Darwin was talking about our distant ancestry,
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2:43 - 2:45our common ancestry with apes.
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2:45 - 2:49And it is quite clear that apes originated on the African continent.
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2:49 - 2:52Around 23 million years ago, they appear in the fossil record.
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2:52 - 2:55Africa was actually disconnected from the other landmasses at that time,
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2:55 - 2:59due to the vagaries of plate tectonics, floating around the Indian Ocean.
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2:59 - 3:01Bumped into Eurasia around 16 million years ago,
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3:01 - 3:04and then we had the first African exodus, as we call it.
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3:04 - 3:06The apes that left at that time ended up in Southeast Asia,
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3:06 - 3:08became the gibbons and the orangutans.
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3:08 - 3:10And the ones that stayed on in Africa
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3:10 - 3:12evolved into the gorillas, the chimpanzees and us.
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3:12 - 3:15So, yes, if you're talking about our common ancestry with apes,
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3:15 - 3:19it's very clear, by looking at the fossil record, we started off here.
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3:19 - 3:21But that's not really the question I'm asking.
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3:21 - 3:23I'm asking about our human ancestry,
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3:23 - 3:26things that we would recognize as being like us
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3:26 - 3:28if they were sitting here in the room.
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3:28 - 3:30If they were peering over your shoulder,
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3:30 - 3:33you wouldn't leap back, like that. What about our human ancestry?
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3:33 - 3:35Because if we go far enough back,
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3:35 - 3:38we share a common ancestry with every living thing on Earth.
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3:38 - 3:41DNA ties us all together, so we share ancestry with barracuda
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3:41 - 3:46and bacteria and mushrooms, if you go far enough back -- over a billion years.
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3:46 - 3:48What we're asking about though is human ancestry.
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3:48 - 3:50How do we study that?
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3:50 - 3:54Well, historically, it has been studied using the science of paleoanthropology.
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3:54 - 3:56Digging things up out of the ground,
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3:56 - 3:58and largely on the basis of morphology --
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3:58 - 4:01the way things are shaped, often skull shape -- saying,
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4:01 - 4:05"This looks a little bit more like us than that, so this must be my ancestor.
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4:05 - 4:08This must be who I'm directly descended from."
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4:08 - 4:11The field of paleoanthropology, I'll argue,
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4:11 - 4:14gives us lots of fascinating possibilities about our ancestry,
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4:14 - 4:17but it doesn't give us the probabilities that we really want as scientists.
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4:17 - 4:19What do I mean by that?
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4:19 - 4:21You're looking at a great example here.
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4:21 - 4:23These are three extinct species of hominids,
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4:23 - 4:25potential human ancestors.
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4:25 - 4:28All dug up just west of here in Olduvai Gorge, by the Leakey family.
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4:28 - 4:30And they're all dating to roughly the same time.
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4:30 - 4:32From left to right, we've got Homo erectus, Homo habilis,
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4:32 - 4:35and Australopithecus -- now called Paranthropus boisei,
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4:35 - 4:40the robust australopithecine. Three extinct species, same place, same time.
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4:40 - 4:43That means that not all three could be my direct ancestor.
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4:43 - 4:46Which one of these guys am I actually related to?
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4:46 - 4:51Possibilities about our ancestry, but not the probabilities that we're really looking for.
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4:52 - 4:56Well, a different approach has been to look at morphology in humans
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4:56 - 4:59using the only data that people really had at hand until quite recently --
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4:59 - 5:01again, largely skull shape.
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5:01 - 5:05The first person to do this systematically was Linnaeus,
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5:05 - 5:07Carl von Linne, a Swedish botanist,
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5:07 - 5:09who in the eighteenth century took it upon himself
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5:09 - 5:11to categorize every living organism on the planet.
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5:11 - 5:13You think you've got a tough job?
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5:13 - 5:15And he did a pretty good job.
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5:15 - 5:19He categorized about 12,000 species in "Systema Naturae."
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5:19 - 5:22He actually coined the term Homo sapiens -- it means wise man in Latin.
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5:22 - 5:26But looking around the world at the diversity of humans, he said,
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5:26 - 5:30"Well, you know, we seem to come in discreet sub-species or categories."
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5:30 - 5:34And he talked about Africans and Americans and Asians and Europeans,
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5:34 - 5:37and a blatantly racist category he termed "Monstrosus,"
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5:37 - 5:40which basically included all the people he didn't like,
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5:40 - 5:43including imaginary folk like elves.
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5:44 - 5:49It's easy to dismiss this as the perhaps well-intentioned
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5:49 - 5:52but ultimately benighted musings of an eighteenth century scientist
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5:52 - 5:54working in the pre-Darwinian era.
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5:54 - 5:56Except, if you had taken physical anthropology
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5:56 - 6:00as recently as 20 or 30 years ago, in many cases you would have learned
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6:00 - 6:02basically that same classification of humanity.
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6:02 - 6:07Human races that according to physical anthropologists of 30, 40 years ago --
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6:07 - 6:09Carlton Coon is the best example --
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6:09 - 6:13had been diverging from each other -- this was in the post-Darwinian era --
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6:13 - 6:16for over a million years, since the time of Homo erectus.
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6:16 - 6:18But based on what data?
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6:18 - 6:22Very little. Very little. Morphology and a lot of guesswork.
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6:22 - 6:24Well, what I'm going to talk about today,
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6:24 - 6:27what I'm going to talk about now is a new approach to this problem.
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6:27 - 6:30Instead of going out and guessing about our ancestry,
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6:30 - 6:32digging things up out of the ground, possible ancestors,
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6:32 - 6:34and saying it on the basis of morphology --
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6:34 - 6:36which we still don't completely understand,
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6:36 - 6:40we don't know the genetic causes underlying this morphological variation --
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6:40 - 6:42what we need to do is turn the problem on its head.
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6:42 - 6:46Because what we're really asking is a genealogical problem,
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6:46 - 6:48or a genealogical question.
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6:48 - 6:53What we're trying to do is construct a family tree for everybody alive today.
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6:53 - 6:55And as any genealogist will tell you --
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6:55 - 6:57anybody have a member of the family, or maybe you
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6:57 - 7:00have tried to construct a family tree, trace back in time?
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7:00 - 7:02You start in the present, with relationships you're certain about.
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7:02 - 7:04You and your siblings, you have a parent in common.
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7:04 - 7:06You and your cousins share a grandparent in common.
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7:06 - 7:09You gradually trace further and further back into the past,
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7:09 - 7:11adding these ever more distant relationships.
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7:11 - 7:15But eventually, no matter how good you are at digging up the church records,
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7:15 - 7:19and all that stuff, you hit what the genealogists call a brick wall.
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7:19 - 7:22A point beyond which you don't know anything else about your ancestors,
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7:22 - 7:26and you enter this dark and mysterious realm we call history
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7:26 - 7:29that we have to feel our way through with whispered guidance.
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7:29 - 7:31Who were these people who came before?
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7:31 - 7:34We have no written record. Well, actually, we do.
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7:34 - 7:37Written in our DNA, in our genetic code --
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7:37 - 7:39we have a historical document that takes us back in time
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7:39 - 7:43to the very earliest days of our species. And that's what we study.
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7:43 - 7:45Now, a quick primer on DNA.
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7:45 - 7:48I suspect that not everybody in the audience is a geneticist.
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7:48 - 7:52It is a very long, linear molecule, a coded version
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7:52 - 7:55of how to make another copy of you. It's your blueprint.
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7:55 - 7:58It's composed of four subunits: A, C, G and T, we call them.
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7:58 - 8:02And it's the sequence of those subunits that defines that blueprint.
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8:02 - 8:05How long is it? Well, it's billions of these subunits in length.
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8:05 - 8:08A haploid genome -- we actually have two copies of all of our chromosomes --
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8:08 - 8:12a haploid genome is around 3.2 billion nucleotides in length.
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8:12 - 8:14And the whole thing, if you add it all together,
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8:14 - 8:16is over six billion nucleotides long.
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8:16 - 8:19If you take all the DNA out of one cell in your body,
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8:19 - 8:23and stretch it end to end, it's around two meters long.
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8:23 - 8:25If you take all the DNA out of every cell in your body,
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8:25 - 8:29and you stretch it end to end, it would reach from here to the moon and back,
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8:29 - 8:32thousands of times. It's a lot of information.
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8:32 - 8:38And so when you're copying this DNA molecule to pass it on, it's a pretty tough job.
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8:38 - 8:42Imagine the longest book you can think of, "War and Peace."
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8:42 - 8:44Now multiply it by 100.
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8:44 - 8:46And imagine copying that by hand.
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8:46 - 8:48And you're working away until late at night,
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8:48 - 8:50and you're very, very careful, and you're drinking coffee
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8:50 - 8:52and you're paying attention, but, occasionally,
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8:52 - 8:54when you're copying this by hand,
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8:54 - 8:56you're going to make a little typo, a spelling mistake --
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8:56 - 9:00substitute an I for an E, or a C for a T.
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9:00 - 9:04Same thing happens to our DNA as it's being passed on through the generations.
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9:04 - 9:07It doesn't happen very often. We have a proofreading mechanism built in.
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9:07 - 9:09But when it does happen, and these changes get transmitted down
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9:09 - 9:12through the generations, they become markers of descent.
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9:12 - 9:14If you share a marker with someone,
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9:14 - 9:17it means you share an ancestor at some point in the past,
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9:17 - 9:19the person who first had that change in their DNA.
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9:19 - 9:22And it's by looking at the pattern of genetic variation,
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9:22 - 9:25the pattern of these markers in people all over the world,
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9:25 - 9:29and assessing the relative ages when they occurred throughout our history,
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9:29 - 9:32that we've been able to construct a family tree for everybody alive today.
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9:32 - 9:35These are two pieces of DNA that we use quite widely in our work.
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9:35 - 9:38Mitochondrial DNA, tracing a purely maternal line of descent.
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9:38 - 9:41You get your mtDNA from your mother, and your mother's mother,
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9:41 - 9:43all the way back to the very first woman.
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9:43 - 9:46The Y chromosome, the piece of DNA that makes men men,
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9:46 - 9:49traces a purely paternal line of descent.
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9:49 - 9:53Everybody in this room, everybody in the world,
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9:53 - 9:57falls into a lineage somewhere on these trees.
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9:57 - 10:00Now, even though these are simplified versions of the real trees,
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10:00 - 10:02they're still kind of complicated, so let's simplify them.
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10:02 - 10:04Turn them on their sides, combine them so that they look like a tree
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10:04 - 10:07with the root at the bottom and the branches going up.
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10:07 - 10:09What's the take-home message?
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10:09 - 10:11Well, the thing that jumps out at you first
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10:11 - 10:14is that the deepest lineages in our family trees
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10:14 - 10:19are found within Africa, among Africans.
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10:19 - 10:22That means that Africans have been accumulating
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10:22 - 10:25this mutational diversity for longer.
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10:25 - 10:29And what that means is that we originated in Africa. It's written in our DNA.
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10:29 - 10:34Every piece of DNA we look at has greater diversity within Africa than outside of Africa.
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10:34 - 10:37And at some point in the past, a sub-group of Africans
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10:37 - 10:41left the African continent to go out and populate the rest of the world.
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10:41 - 10:43Now, how recently do we share this ancestry?
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10:43 - 10:47Was it millions of years ago, which we might suspect
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10:47 - 10:50by looking at all this incredible variation around the world?
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10:50 - 10:53No, the DNA tells a story that's very clear.
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10:53 - 10:58Within the last 200,000 years, we all share an ancestor, a single person --
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10:58 - 11:02Mitochondrial Eve, you might have heard about her -- in Africa,
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11:02 - 11:05an African woman who gave rise to all the mitochondrial diversity in the world today.
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11:05 - 11:07But what's even more amazing
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11:07 - 11:09is that if you look at the Y-chromosome side,
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11:09 - 11:13the male side of the story, the Y-chromosome Adam
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11:13 - 11:15only lived around 60,000 years ago.
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11:15 - 11:18That's only about 2,000 human generations,
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11:18 - 11:21the blink of an eye in an evolutionary sense.
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11:22 - 11:25That tells us we were all still living in Africa at that time.
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11:25 - 11:27This was an African man who gave rise
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11:27 - 11:29to all the Y chromosome diversity around the world.
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11:29 - 11:31It's only within the last 60,000 years
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11:31 - 11:35that we have started to generate this incredible diversity we see around the world.
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11:35 - 11:37Such an amazing story.
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11:37 - 11:40We're all effectively part of an extended African family.
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11:41 - 11:44Now, that seems so recent. Why didn't we start to leave earlier?
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11:44 - 11:48Why didn't Homo erectus evolve into separate species,
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11:48 - 11:50or sub-species rather, human races around the world?
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11:50 - 11:54Why was it that we seem to have come out of Africa so recently?
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11:54 - 11:56Well, that's a big question. These "why" questions,
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11:56 - 12:01particularly in genetics and the study of history in general, are always the big ones,
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12:01 - 12:03the ones that are tough to answer.
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12:03 - 12:06And so when all else fails, talk about the weather.
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12:06 - 12:09What was going on to the world's weather around 60,000 years ago?
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12:09 - 12:12Well, we were going into the worst part of the last ice age.
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12:12 - 12:15The last ice age started roughly 120,000 years ago.
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12:15 - 12:19It went up and down, and it really started to accelerate around 70,000 years ago.
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12:19 - 12:21Lots of evidence from sediment cores
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12:21 - 12:24and the pollen types, oxygen isotopes and so on.
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12:24 - 12:27We hit the last glacial maximum around 16,000 years ago,
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12:27 - 12:31but basically, from 70,000 years on, things were getting really tough,
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12:31 - 12:36getting very cold. The Northern Hemisphere had massive growing ice sheets.
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12:36 - 12:40New York City, Chicago, Seattle, all under a sheet of ice.
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12:40 - 12:45Most of Britain, all of Scandinavia, covered by ice several kilometers thick.
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12:45 - 12:48Now, Africa is the most tropical continent on the planet --
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12:48 - 12:52about 85 percent of it lies between Cancer and Capricorn --
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12:52 - 12:54and there aren't a lot of glaciers here,
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12:54 - 12:56except on the high mountains here in East Africa.
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12:56 - 12:59So what was going on here? We weren't covered in ice in Africa.
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12:59 - 13:02Rather, Africa was drying out at that time.
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13:02 - 13:04This is a paleo-climatological map
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13:04 - 13:07of what Africa looked like between 60,000 and 70,000 years ago,
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13:07 - 13:11reconstructed from all these pieces of evidence that I mentioned before.
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13:11 - 13:15The reason for that is that ice actually sucks moisture out of the atmosphere.
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13:15 - 13:19If you think about Antarctica, it's technically a desert, it gets so little precipitation.
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13:19 - 13:21So the whole world was drying out.
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13:21 - 13:25The sea levels were dropping. And Africa was turning to desert.
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13:25 - 13:28The Sahara was much bigger then than it is now.
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13:28 - 13:31And the human habitat was reduced to just a few small pockets,
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13:31 - 13:33compared to what we have today.
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13:33 - 13:35The evidence from genetic data
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13:35 - 13:38is that the human population around this time, roughly 70,000 years ago,
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13:38 - 13:41crashed to fewer than 2,000 individuals.
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13:41 - 13:45We nearly went extinct. We were hanging on by our fingernails.
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13:45 - 13:48And then something happened. A great illustration of it.
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13:48 - 13:50Look at some stone tools.
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13:50 - 13:54The ones on the left are from Africa, from around a million years ago.
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13:54 - 13:57The ones on the right were made by Neanderthals, our distant cousins,
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13:57 - 13:59not our direct ancestors, living in Europe,
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13:59 - 14:03and they date from around 50,000 or 60,000 years ago.
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14:03 - 14:06Now, at the risk of offending any paleoanthropologists
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14:06 - 14:09or physical anthropologists in the audience,
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14:09 - 14:14basically there's not a lot of change between these two stone tool groups.
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14:14 - 14:17The ones on the left are pretty similar to the ones on the right.
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14:17 - 14:21We are in a period of long cultural stasis from a million years ago
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14:21 - 14:23until around 60,000 to 70,000 years ago.
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14:23 - 14:25The tool styles don't change that much.
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14:25 - 14:27The evidence is that the human way of life
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14:27 - 14:29didn't change that much during that period.
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14:29 - 14:34But then 50, 60, 70 thousand years ago, somewhere in that region,
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14:34 - 14:37all hell breaks loose. Art makes its appearance.
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14:37 - 14:40The stone tools become much more finely crafted.
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14:40 - 14:42The evidence is that humans begin to specialize in particular prey species,
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14:43 - 14:45at particular times of the year.
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14:45 - 14:48The population size started to expand.
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14:48 - 14:50Probably, according to what many linguists believe,
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14:50 - 14:54fully modern language, syntactic language -- subject, verb, object --
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14:54 - 14:58that we use to convey complex ideas, like I'm doing now, appeared around that time.
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14:58 - 15:02We became much more social. The social networks expanded.
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15:02 - 15:07This change in behavior allowed us to survive these worsening conditions in Africa,
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15:07 - 15:11and they allowed us to start to expand around the world.
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15:12 - 15:15We've been talking at this conference about African success stories.
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15:15 - 15:18Well, you want the ultimate African success story?
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15:18 - 15:21Look in the mirror. You're it. The reason you're alive today
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15:21 - 15:25is because of those changes in our brains that took place in Africa --
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15:25 - 15:28probably somewhere in the region where we're sitting right now,
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15:28 - 15:31around 60, 70 thousand years ago --
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15:31 - 15:34allowing us not only to survive in Africa, but to expand out of Africa.
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15:34 - 15:37An early coastal migration along the south coast of Asia,
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15:37 - 15:39leaving Africa around 60,000 years ago,
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15:39 - 15:43reaching Australia very rapidly, by 50,000 years ago.
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15:43 - 15:45A slightly later migration up into the Middle East.
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15:45 - 15:47These would have been savannah hunters.
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15:47 - 15:49So those of you who are going on one of the post-conference tours,
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15:49 - 15:51you'll get to see what a real savannah is like.
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15:51 - 15:53And it's basically a meat locker.
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15:53 - 15:56People who would have specialized in killing the animals,
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15:56 - 15:59hunting the animals on those meat locker savannahs, moving up,
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15:59 - 16:03following the grasslands into the Middle East around 45,000 years ago,
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16:03 - 16:05during one of the rare wet phases in the Sahara.
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16:05 - 16:08Migrating eastward, following the grasslands,
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16:08 - 16:10because that's what they were adapted to live on.
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16:10 - 16:12And when they reached Central Asia,
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16:12 - 16:15they reached what was effectively a steppe super-highway,
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16:15 - 16:17a grassland super-highway.
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16:17 - 16:19The grasslands at that time -- this was during the last ice age --
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16:19 - 16:22stretched basically from Germany all the way over to Korea,
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16:22 - 16:24and the entire continent was open to them.
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16:24 - 16:26Entering Europe around 35,000 years ago,
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16:26 - 16:28and finally, a small group migrating up
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16:28 - 16:32through the worst weather imaginable, Siberia,
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16:32 - 16:34inside the Arctic Circle, during the last ice age --
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16:34 - 16:38temperature was at -70, -80, even -100, perhaps --
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16:38 - 16:42migrating into the Americas, ultimately reaching that final frontier.
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16:42 - 16:46An amazing story, and it happened first in Africa.
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16:46 - 16:48The changes that allowed us to do that,
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16:48 - 16:51the evolution of this highly adaptable brain that we all carry around with us,
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16:51 - 16:53allowing us to create novel cultures,
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16:53 - 16:56allowing us to develop the diversity
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16:56 - 16:59that we see on a whirlwind trip like the one I've just been on.
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17:00 - 17:04Now, that story I just told you is literally a whirlwind tour
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17:04 - 17:09of how we populated the world, the great Paleolithic wanderings of our species.
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17:09 - 17:11And that's the story that I told a couple of years ago
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17:11 - 17:15in my book, "The Journey of Man," and a film that we made with the same title.
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17:15 - 17:18And as we were finishing up that film --
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17:18 - 17:20it was co-produced with National Geographic --
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17:20 - 17:23I started talking to the folks at NG about this work.
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17:23 - 17:27And they got really excited about it. They liked the film, but they said,
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17:27 - 17:29"You know, we really see this as kind of
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17:29 - 17:33the next wave in the study of human origins, where we all came from,
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17:33 - 17:38using the tools of DNA to map the migrations around the world.
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17:38 - 17:40You know, the study of human origins is kind of in our DNA,
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17:40 - 17:42and we want to take it to the next level.
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17:42 - 17:44What do you want to do next?"
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17:44 - 17:46Which is a great question to be asked by National Geographic.
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17:46 - 17:50And I said, "Well, you know, what I've sketched out here is just that.
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17:50 - 17:54It is a very coarse sketch of how we migrated around the planet.
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17:54 - 17:57And it's based on a few thousand people we've sampled from,
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17:57 - 17:59you know, a handful of populations around the world.
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17:59 - 18:03Studied a few genetic markers, and there are lots of gaps on this map.
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18:03 - 18:05We've just connected the dots. What we need to do
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18:05 - 18:09is increase our sample size by an order of magnitude or more --
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18:09 - 18:13hundreds of thousands of DNA samples from people all over the world."
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18:13 - 18:16And that was the genesis of the Genographic Project.
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18:16 - 18:19The project launched in April 2005.
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18:19 - 18:23It has three core components. Obviously, science is a big part of it.
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18:23 - 18:26The field research that we're doing around the world with indigenous peoples.
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18:26 - 18:29People who have lived in the same location for a long period of time
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18:29 - 18:31retain a connection to the place where they live
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18:31 - 18:33that many of the rest of us have lost.
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18:34 - 18:36So my ancestors come from all over northern Europe.
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18:36 - 18:39I live in the Eastern Seaboard of North America when I'm not traveling.
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18:39 - 18:42Where am I indigenous to? Nowhere really. My genes are all jumbled up.
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18:42 - 18:45But there are people who retain that link to their ancestors
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18:45 - 18:48that allows us to contextualize the DNA results.
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18:48 - 18:50That's the focus of the field research,
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18:50 - 18:52the centers that we've set up all over the world --
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18:52 - 18:5510 of them, top population geneticists.
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18:55 - 18:58But, in addition, we wanted to open up this study to anybody around the world.
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18:58 - 19:02How often do you get to participate in a big scientific project?
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19:02 - 19:04The Human Genome Project, or a Mars Rover mission.
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19:04 - 19:06In this case, you actually can.
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19:06 - 19:10You can go onto our website, Nationalgeographic.com/genographic.
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19:10 - 19:13You can order a kit. You can test your own DNA.
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19:13 - 19:16And you can actually submit those results to the database,
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19:16 - 19:18and tell us a little about your genealogical background,
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19:18 - 19:22have the data analyzed as part of the scientific effort.
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19:22 - 19:26Now, this is all a nonprofit enterprise, and so the money that we raise,
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19:26 - 19:29after we cover the cost of doing the testing and making the kit components,
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19:29 - 19:31gets plowed back into the project.
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19:31 - 19:33The majority going to something we call the Legacy Fund.
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19:33 - 19:37It's a charitable entity, basically a grant-giving entity
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19:37 - 19:39that gives money back to indigenous groups around the world
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19:39 - 19:43for educational, cultural projects initiated by them.
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19:43 - 19:45They apply to this fund in order to do various projects,
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19:45 - 19:47and I'll show you a couple of examples.
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19:47 - 19:50So how are we doing on the project? We've got about 25,000 samples
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19:50 - 19:52collected from indigenous people around the world.
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19:52 - 19:55The most amazing thing has been the interest on the part of the public;
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19:55 - 19:58210,000 people have ordered these participation kits
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19:58 - 20:00since we launched two years ago,
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20:00 - 20:03which has raised around five million dollars,
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20:03 - 20:06the majority of which, at least half, is going back into the Legacy Fund.
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20:06 - 20:10We've just awarded the first Legacy Grants totaling around 500,000 dollars.
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20:10 - 20:13Projects around the world -- documenting oral poetry in Sierra Leone,
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20:13 - 20:16preserving traditional weaving patterns in Gaza,
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20:16 - 20:19language revitalization in Tajikistan, etc., etc.
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20:19 - 20:22So the project is going very, very well,
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20:22 - 20:26and I urge you to check out the website and watch this space.
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20:26 - 20:28Thank you very much.
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20:28 - 20:30(Applause)
- Title:
- A family tree for humanity
- Speaker:
- Spencer Wells
- Description:
-
All humans share some common bits of DNA, passed down to us from our African ancestors. Geneticist Spencer Wells talks about how his Genographic Project will use this shared DNA to figure out how we are -- in all our diversity -- truly connected.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 20:30
TED edited English subtitles for A family tree for humanity | ||
TED added a translation |