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00:00Deep inside each one of us, a story is waiting to be told.
00:09A story of adventure and survival.
00:14It begins in Africa with the dawn of humanity.
00:18Travels through epic droughts and ice ages
00:22and takes us to the ends of the Earth.
00:25To tell this story, we begin with a bold experiment.
00:33On a single day, on a single street, with the DNA of just a handful of people,
00:40we set out to trace the ancient journeys of every person alive today
00:45and reveal how we are all connected on the human family tree.
00:55It's the quintessential melting pot.
01:03For centuries, people from all over the globe have come to New York
01:09in search of a better life.
01:11Along the East River, just across from Manhattan, we find they've never stopped coming.
01:16This is one of the most cosmopolitan places on Earth.
01:17This is one of the most cosmopolitan places on Earth.
01:48The district of Queens, New York City, in the United States of America.
01:54Here in Queens, people are flocking to the 30th Avenue Street Fair,
01:59where geneticist Spencer Wells and his team are on a mission.
02:06Just on one side. It's fine.
02:09Using the DNA from a selection of people,
02:11they are attempting to retrace humanity's journey to all corners of the Earth
02:16from the individuals on this one street.
02:23This place is really a microcosm of the world.
02:26You've got people from all over the planet just walking around on this one street.
02:30I mean, today we've been talking to people from Bangladesh,
02:33people from Thailand, people from Pakistan, Ecuador,
02:36all over the Afro-Caribbean region.
02:38I mean, it's an amazing opportunity.
02:46The swabbing here today is part of a National Geographic project
02:50called the Genographic Project.
02:52Over the last four years,
02:54DNA has been collected from 350,000 people around the world.
02:59Honey, did you wash your teeth in the morning?
03:02It is basically a quest to understand, you know, where we all came from.
03:06That's one of those key human questions
03:08that everybody is kind of searching for the answer to.
03:11And, you know, who am I?
03:12Who are my ancestors?
03:13And we're using the tools of science to get the answers to that.
03:16Where do you want?
03:17Oh, I like that.
03:18I like that.
03:18That's great.
03:20Now, hundreds of New Yorkers are lining up
03:22to get their questions answered
03:24and to learn about their own ancient pasts.
03:29He's very excited about it
03:31and he thinks that he's going to change his life.
03:35Most of us are able to trace our ancestors back
03:39about four or five generations
03:40to a great-great-grandparent, perhaps.
03:44This is your deep, deep ancestor.
03:45So we're not necessarily your grandparents.
03:47And if we're lucky, we know where these ancestors lived.
03:51These DNA tests tell a deeper story.
03:55Rather than taking us back just a handful of generations,
03:59they take us back many thousands.
04:00We descend from a small group of Homo sapiens
04:06who began eking out a life in Africa
04:09around 200,000 years ago.
04:15People didn't leave Africa until much later
04:18when hard times or greener pastures led them out.
04:21Our ancient connections may not be immediately obvious.
04:33Our ancestors adapted to different climates
04:35and, as a result, humans are now among
04:37the most physically varied-looking species on the planet.
04:41But looks can be deceiving.
04:46Hold that.
04:47There.
04:48Look right here.
04:49This is great.
04:51Let's do one more.
04:53Light or dark, big or small,
04:56with curly or straight hair,
04:58and brown or blue eyes,
05:00minuscule genetic changes account for all of our differences.
05:05To track our ancient paths, though,
05:08scientists study DNA that stays very much the same.
05:13In men like George Delis, it's a Y chromosome.
05:16Hold it. Let's do one more.
05:18It's been passed down the line from father to son
05:23over thousands of generations,
05:25and ultimately traces back to one man
05:28who lived in Africa around 60,000 years ago.
05:31We'll call him scientific Adam.
05:32We'll call him scientific Adam.
05:38For women, like Nezla Dermagy, the DNA comes from special cell structures called mitochondria,
05:46which both men and women carry, but only mothers pass down.
05:50These trace back to one woman who lived in Africa between 150,000 to 200,000 years ago.
06:03We'll call her scientific Eve.
06:05She is the oldest root of our family tree.
06:13For everyone alive today, Africa is where the journey begins.
06:20Wow.
06:21No words.
06:22I can believe that the people come from Africa.
06:25We are from Bangladesh.
06:27This is very exciting.
06:28A lot of people know their mother's mother's mother's path or their father's father's father's path.
06:31It's only the first surprise for our New Yorkers.
06:35The genographic team will soon piece together the findings
06:38and reveal their unique genetic results.
06:42With a little luck, they've got the right mix of DNA
06:44to take us all back to our beginnings in Africa
06:47and plot our many amazing journeys out.
06:50It's an epic saga full of twists and turns,
07:06and it begins where life begins.
07:11She doesn't know it yet, but Kerry Nicholson-Gonzalez
07:14has just passed along to her newborn baby Leo
07:17what other mothers have for tens of thousands of years.
07:21Genetic markers that link her son to the birth of us all.
07:39Like so many others who call this place home,
07:42Kerry isn't a native New Yorker.
07:44A third-generation American, born and raised in Ohio,
07:48she left a small town in the American Midwest for life in the big city.
07:55I moved to New York in the summer of 2000
07:58to pursue dance and life and see what happens.
08:07Kerry is a professional dancer
08:09and teaches Pilates.
08:11She got married
08:14and started a family here.
08:24Yet, as is the case for many trying to build a life
08:27in a strange new home,
08:29Kerry still clings tightly to her old one.
08:31Kerry's photographs and records date back to her European roots
08:39in Slovenia, more than 100 years ago.
08:42They're pretty priceless.
08:44This is what has come to make my life.
08:49And all of these people,
08:50if they didn't all come together,
08:52then I wouldn't be here.
08:55Good job.
08:56While Kerry can trace back about three generations,
08:59her DNA can take her back more than 6,000 generations,
09:04across many lands,
09:05to her most ancient of grandmothers,
09:08Scientific Eve.
09:09At that time,
09:24there were few humans on the planet,
09:26living somewhere between eastern or southern Africa.
09:30Eve and this small band of people
09:31set the stage for us all,
09:33one baby at a time.
09:39Despite all the babies
09:41that have come between Eve and Kerry,
09:43their DNA is still 99.9% similar.
09:49To trace our ancestries,
09:51scientists have to investigate
09:52the 0.1% that's different
09:54through tiny, random changes
09:56to the A's, C's, G's and T's
10:00that accumulate in our genetic codes over time.
10:03Scientists call them markers.
10:06They don't change the way you look
10:08or give you a disease
10:09or make you better than anyone else.
10:11They're just baggage
10:11that gets passed on through the generations.
10:16200,000 years ago,
10:19the DNA in Scientific Eve's mitochondria
10:21picked up some of these random changes.
10:25An A became a G.
10:28Some T's became C's.
10:30She unknowingly passed those changes
10:35along to her daughters
10:36and her daughters onto their daughters
10:39down the line over thousands of generations
10:42to Kerry and every other person on the planet.
10:50Tiny, seemingly random changes to our DNA
10:53over generations are known as markers.
10:55They allow us to connect people through history.
10:59Since they crop up at a fairly steady rate,
11:02markers also serve as a kind of clock
11:04to estimate when people lived.
11:09And by looking at how markers cluster,
11:12they can even act as roadmaps
11:13to show us where our ancestors came from
11:16and where they moved.
11:17So in Kerry's case,
11:22she is a member of haplogroup J.
11:24I actually belong to the same genetic lineage.
11:27I'm a J too.
11:30J is a relatively recent marker
11:32found commonly in Europe,
11:33the end of the road for Kerry's ancestors.
11:37A little further back in time,
11:38we find the J connect to the R in the Middle East.
11:42N before that,
11:44and ultimately all the way back to Africa,
11:46the one place on Earth
11:48where all of our DNA converges.
11:55And according to our DNA clocks,
11:58before taking a single step out of Africa,
12:00we stayed there for a long time,
12:03as much as three-quarters of our history as a species,
12:06some 140,000 years.
12:09To find out what may have ultimately forced us out,
12:18scientists compare the DNA of people who left Africa
12:20with those who never did.
12:23Indigenous groups like the San Bushmen of Southern Africa.
12:26The San are universally accepted
12:39to be the world's oldest genetically distinct population of humans,
12:43even if nowadays their cultural links to the past
12:46are mostly for the sake of tourists.
12:48their markers connect them to Scientific Eve,
12:58but split off from the ret of humanity soon after.
13:08Recently, the Genographic Project
13:10used DNA from this San
13:12to help pinpoint some of our earliest movements in Africa.
13:19This time,
13:20they compared the genes of the San
13:22with other African groups,
13:24like those who live about 2,400 kilometers north of the San,
13:28near Tanzania's Serengeti.
13:30The Hadzabe.
13:43The Hadzabe, like the San,
13:45connect back to Scientific Eve.
13:47But by studying differences in their DNA,
13:50scientists revealed that by around 150,000 years ago,
13:55our founding population had split in two.
14:00It's the first branch on our family tree.
14:09The earliest major movement of people our genes have measured.
14:16One group became the ancestors of the San,
14:19the other the ancestors of the Hadzabe
14:21and other African groups,
14:24and ultimately, the entire rest of the world.
14:30It's the first branch on our planet.
14:32No one knows exactly what led to this split,
14:35but all signs point to climate.
14:39Slight changes in the Earth's orbit ushered in a new ice age,
14:43and climate shifted for 100,000 years.
14:47In the Northern Hemisphere, that meant ice and cold.
14:52But in Africa, things became blisteringly dry.
14:55This period lasted thousands of years.
15:04Geneticists say it was the bleakest in our history.
15:10Huddled around shrinking sources of water,
15:13our ancestors were hanging on by a thread.
15:15No one knows how big the initial human population was,
15:21but based on the lack of genetic variation during these drought years,
15:26the number dropped to as few as 2,000 people.
15:30We were an endangered species.
15:32The state of Nebraska is locked in one of its worst dry spells in decades,
15:38as high temperatures and dry conditions shrivel crops
15:41and have farmers praying for...
15:43Somehow, these people made it through the population crunch.
15:47If they hadn't, Kerry wouldn't be here,
15:50nor would any of the rest of us.
15:52...the farmers plant drought-resistant crops
15:53and offer tips about how to keep fields as moist as possible.
15:57Around 70,000 years ago,
16:01climate studies indicate the drought in Africa eases for a time.
16:08Archaeological evidence reveals tools cropping up all across the continent.
16:13And the genetics show new lineages taking root.
16:21The human population was growing again,
16:24and it would continue to grow.
16:27We haven't shared any of this with Kerry yet,
16:34just whetted her appetite for her results.
16:38It's kind of sparked this desire to really go back
16:42and try to understand who was who
16:44and how you were related,
16:46especially now that Leo's here.
16:49There is a lot more to know
16:50than just the few steps back that we know
16:54and that we have pictures for.
16:57Kerry's ancient ancestors would soon take some steps
17:01that changed the world forever.
17:03They left Africa behind.
17:05In a Thai restaurant in Queens,
17:27in the DNA of a waitress and a chef,
17:30we find clues about the people
17:31who take those first fateful steps out of Africa.
17:34And curry, meat, vegetables.
17:38Okay, and...
17:40Thao Sidi and Kreen Krei Tang Chik Tsumran share similar ethnic backgrounds.
17:46Both trace their recent ancestry to China and Thailand.
17:50Both came to New York and left family behind.
17:53That's my great-grandmother.
17:55That's my great-grandmother.
17:57This is my grandmother and my grandfather.
17:59I talk to them all the time, you know,
18:02how's grandma doing and she was like,
18:04oh, you know, you save money, you come back to Thailand,
18:07you open a business.
18:09You're welcome.
18:10Kreen Krei and Tau's ancient lineages are very different.
18:16Kreen Krei's DNA shows us how people spread from Africa all across Asia.
18:21But only Tau, who declined to talk to us on camera,
18:25has markers tracing back to those very first people who left.
18:29Her marker, known as N-Star, is found throughout Asia,
18:38as well as in indigenous groups on islands in the Pacific and Australia.
18:47There is a lot we don't know about why Tau's ancestors left Africa,
18:52let alone how they populated islands in the Pacific Ocean.
18:55Until recently, most scientists believed people took a northern route out of Africa,
19:04across the Sinai and into the Middle East.
19:09But since that required crossing the Sahara Desert,
19:12many are now looking further south.
19:17At the southern tip of the Red Sea,
19:19Africa is a mere 28 kilometers from the Arabian Peninsula.
19:25It's unclear if people would have seen the other side back then,
19:35but birds, dust, perhaps a forest fire would have signalled something was out there.
19:46They may have walked, swam or rafted,
19:49but around 60,000 years ago, the genetics indicate they left.
19:55Once they reached the Arabian Peninsula,
20:08there was nothing to get in their way.
20:10But the country was more and more.
20:20Skillful fishermen, they found a limitless supply of seafood for thousands of kilometers.
20:28They journeyed along the coasts of Iran and Pakistan,
20:32Pakistan, down and around India, all the way into Southeast Asia.
20:45Tao's ancestors made it to Thailand by around 50,000 years ago.
20:50But while many with her marker chose to stay put there,
20:54the climate at the time allowed many more to venture further.
20:57Today, miles of ocean separate mainland Asia from the islands of Java, Sumatra and Borneo.
21:07But during the Ice Age, when vast amounts of our oceans were frozen at the poles,
21:13Earth was a very different place.
21:20In the warm tropics, sea levels were around 100 metres lower.
21:25As a result, what are islands today, were linked up.
21:36One continuous land mass connected Asia with southern Indonesia, just north of Australia.
21:43People could walk all the way to Java without getting their feet wet.
21:49But the story doesn't end there.
21:58Some of Tao's ancestors stayed in Southeast Asia.
22:02But their markers are found as far away as Australia and people like the Aborigines.
22:07To reach there, even with the lower sea levels at the time,
22:13they still had to contend with some 70 kilometres of open water.
22:25Whether they set out to reach a new continent or drifted to it,
22:28around 45,000 years ago, modern humans landed in Australia.
22:34In the mountains of the Philippines,
22:53geneticist Spencer Wells and his colleagues are distributing genetic results
22:57to an indigenous group here called the Aita.
23:01Okay, everyone, if you could come gather a rent here.
23:06Small in stature, these curly-haired, dark-skinned people number only about 20,000 strong.
23:14And that there are the people with the curly hair and the people with the straight hair.
23:18Much of the Aita's ancient DNA has been diluted through the ages.
23:25And scientists are still hashing out the details.
23:28But it appears their ancestors took the same coastal migration out of Africa that Tao's did.
23:37They walked to these islands back when sea levels were low.
23:41And when the Ice Age began waning about 11,000 years ago,
23:44they got cut off from the rest of the world.
23:50Since the tropical climate wouldn't have been much different than Africa's,
23:54their African features hardly changed.
24:02Tao's, on the other hand, obviously did.
24:05And it turns out, Queen Cry's ancestors were responsible.
24:08They moved eastward out of Africa sometime later than Tao's did,
24:14following a much colder inland route.
24:18They lived in isolation somewhere around China for thousands of years,
24:23where they probably adapted to the frigid Ice Age climate
24:26before heading south and mingling with Tao's ancestors.
24:29Around 40,000 years ago, Queen Cry's ancient family was also quite prolific,
24:40ultimately swapping DNA with Tao's.
24:43While Tao's ancestors kept the n-star marker, they lost their African appearances.
24:49This will all come as a shock to Queen Cry.
24:52He'll soon learn that as far as his maternal ancestry is concerned,
24:57he has less DNA in common with Tao than he does with our next New Yorker,
25:02an immigrant from Turkey.
25:22They lost their own black people.
25:23They lost their own family.
25:25They lost their own family.
25:27They lost their own family.
25:28They lost their own family.
25:29And their parents did have a huge difference in sea.
25:32Which is the same, but they still fought there.
25:34They lost their own family.
25:36And together with their own family.
25:37Centered and theumentalists have been found in space.
25:39It's probably a very rare in the world.
25:41They were very rare to 가능 at the core of the New Yorker.
25:43They lost their own holiday.
25:45They lost their own family and the Celtic community in the world.
25:48I wish they wanted to be more...
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