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00:00There is a place on this planet where some say all memory began.
00:10For over four million years, Lake Turkana in the north of Kenya has witnessed the rise
00:15and fall of species too many to count.
00:22One of them struggled like all others, but then walked out of Africa and on to dominate
00:28the world.
00:30It is this species, we and our ancestors, that has preoccupied the life of one man.
00:40For over 40 years, Richard Leakey, paleontologist, statesman, conservationist, provocateur, has
00:47scoured this harsh land to find out how we became who we are and what it means to be
00:53human.
00:55All of us are genetically related.
00:58What happened to the ones before us?
00:59In other words, where the line starts in Africa, who were they?
01:05He believes a variety of human-like creatures once lived here.
01:10In many ways, he can see them.
01:12Will they be real to us as well?
01:15And can we see ourselves in them?
01:18I think part of the problem is that people are uncomfortable with the idea that humanity
01:22itself has originated from something that looked very different from what we look like
01:27today.
01:28But evolution happened.
01:29We have fossils to show it.
01:31It's a fact.
01:35But how did it happen?
01:37And why did it happen here?
01:40Can Richard and his team find the roots of our humanity in this, the most formative of
01:45all landscapes, the place of all our pasts?
01:52Now join Richard Leakey on the search for the bones of Turkana.
02:22Joseph's face was black as night, the pale yellow moon shone through his eyes.
02:52His path was marked by the stars of the southern hemisphere, and he walked his days under African
03:06skies.
03:09This is the story of how we begin to remember.
03:15This is the powerful pulsing of love in a vein.
03:21After the dream of falling and calling your name out, these are the roots of rhythm, and
03:29the roots of rhythm remain.
03:36If there is a beginning of memory, it may be of this lake and its shores.
03:43This might be the Africa where human life began.
03:49And if there is anyone who knows the stuff of those memories, it is this man.
03:55For over 40 years, Richard Leakey and his family have been returning here in search
04:01of our ancestry, staking their careers on a desert lake.
04:11Aimed for speaking out and taking risks, Richard Leakey believes that if one place
04:16has witnessed every stage of human evolution, it is Turkana.
04:21I've had a lifelong ambition to understand the origins of our species.
04:25I want to go from the present all the way back through the various stages leading to
04:30the very first glimmerings of the human story.
04:33I'm absolutely certain that Turkana is the key to understanding humanity.
04:41If you get to the point that you don't care less about the evolution of a buffalo or a
04:47butterfly, you are probably somewhat of an intellectual pygmy.
04:53I think it's fascinating how life has come into existence.
04:56I think it's incredible what has happened.
04:59This world and the life on it is a process that has many extraordinary events.
05:06And it's of huge intellectual, personal value to me to understand as much as I can.
05:20Richard is the third generation of Leakey family to live and work in Africa.
05:26His parents, Louis and Mary Leakey, were pioneering anthropologists whose discoveries
05:32helped affirm that Africa was the cradle of mankind.
05:36But Richard, the scion of this famous tribe, wanted nothing to do with the family business.
05:44As a youngster, I had absolutely no intention of following in my parents' footsteps.
05:48I thought it was desperately boring.
05:51But in 1967, I was doing some work for my father in Ethiopia, and I realized that I was interested.
05:57But even though I was interested, I wanted my own patch.
06:01And it just happened that I flew over Lake Turkana and realized that nobody had looked there before.
06:08And it was a long way from nowhere.
06:10But there was a helicopter nearby, and so when I flew down with the helicopter,
06:14it was really to ground truth what I'd seen from the air.
06:20Surprising everybody at the age of 23, without a college degree or even a high school diploma,
06:26Richard convinced the National Geographic Society to give him grant money for his own overland expedition.
06:36It was a chance to get off for three months on somebody else's money and be a sort of boy scout and have fun.
06:44And as it happened, we found a lot of things, and I knew then we could market the success of that expedition
06:49to get more money to go on having fun.
06:52I hate doing things that aren't fun.
06:55And it was superb fun.
06:57Every day of every year at Turkana was just an adventure,
07:01a sort of dream for a young man looking for adventure.
07:08So began Richard's impassioned career at Turkana,
07:12a place where the constant presence of water has nurtured a wide variety of life.
07:19New geologic and climate data present a picture of how the lake has evolved over the last four million years.
07:27Today Lake Turkana lies in a very, very dry, arid area.
07:32But it's also been a fantastic savanna.
07:36Over the last four million years, this environment has changed.
07:39The lake hasn't always been there.
07:41It's been a big lake, a small lake.
07:43There's been no lake, but there's always been water.
07:46And it's been a place where life has been able to hang on, albeit under pressure.
07:53And I believe we have at Turkana a remarkably complete record of the last four million years.
08:06So what are we going to look for today?
08:08The honko that is showing.
08:10It's just showing?
08:11The edge.
08:12And the rest is in situ?
08:13Yeah, probably.
08:15Richard's patch is now worked by his wife, Meve, his daughter, Louise,
08:20and their crack team of fossil hunters.
08:23Each year, wind and rain uncover more secrets in the sand.
08:30Oh, wow, look at this.
08:32What is this?
08:34Pellorovis?
08:36Percornensis, if you want to be really exact.
08:39That's definitely Pellorovis.
08:41The fossilized horn of an animal called Pellorovis,
08:44a giant buffalo that lived at the same time as our ancestors,
08:48one and a half million years ago.
08:52The Turkana landscape at that time was filled with a diverse population of creatures,
08:58both outlandish and familiar.
09:01Some survived, but many, like this giant buffalo, went extinct.
09:07It sure goes on in.
09:09Well, it would be nice if there were more than just the one in here, wouldn't it?
09:13We need to take this little hill.
09:15Yeah, take the hill off and dig around there.
09:18Look, it's sand. It's nice and soft.
09:20Yeah, it does look like it's in there.
09:22Fantastic.
09:25Meve and Louise believe that one way to see the total picture of human life at Turkana
09:31is to understand the creatures that shared the lake with us.
09:35I wonder whether these hominids were killing these Pellorovis.
09:39That's a lot of meat on a big old buffalo like that.
09:42No, I think they were definitely hunting by this stage.
09:45I think they were definitely killing them.
09:47In fact, other giant buffalo fossils found nearby exhibit cut marks,
09:53like these on a related species, evidence of ancient butchery.
09:58Anyway, we'll keep that somewhere.
10:00The challenge for Louise and Meve is to determine
10:03which one of our ancestors put giant buffalo on the menu.
10:08Well, I think it's going to be a left horn, and this will be the tip,
10:13and then we're going to have more of it going in there.
10:16That's my take on this one.
10:20My mother and I have an unusual relationship
10:23in that we work together and that we get on very well as mother and daughter.
10:28Louise is very like Richard in many, many ways.
10:31She has a very direct way of looking at things.
10:34I grew up joining her on expeditions since I was very young,
10:38and so it sort of comes naturally to me to know what to do in the field.
10:42She's good at logistics, she's good at science, she's good at everything.
10:47Well, I'm not doing very well here. Look, I've just hoofed the rib.
10:50Got that off.
10:51These are very long, hot days,
10:53and so you've got to keep each other amused and entertained,
10:56and so there's this constant banter.
10:59And, you know, the fieldwork's fun.
11:01Ooh-hoo!
11:02There's a little face coming out, is there?
11:05Or a big face.
11:08Yes, as you say, they were big animals, these.
11:10Look at the size of that horn.
11:12You get belly-tossed by a pair of horns like that, don't you?
11:15That size.
11:16But, you know, you're quite awkward.
11:18They're one meter either side of you.
11:20How would you get something to toss?
11:23It's easier if you're a buffalo with a short one, don't you think?
11:26Well, that's all that we know about.
11:28I think those great big long ones were for display.
11:30Make the females think they were nice.
11:39Once protected in plaster,
11:41this giant buffalo will join a collection of fossils.
11:44A growing menagerie of clues to ancient human life.
11:48Oh, it would be fantastic.
11:50With that complete scarf.
11:51It would definitely be worth doing.
11:54On his first Turkana expedition in 1968,
11:57Richard and his team found few clues.
12:01In 1969, he returned,
12:03this time with his colleague and wife-to-be, Niamh.
12:08Two weeks into the season, with little to show for it,
12:11they made an astonishing discovery.
12:16We really hadn't seen very much,
12:18and we were getting a bit fed up.
12:20And it was very, very hot that day.
12:22And suddenly he let out an exclamation.
12:24Good heavens.
12:25And I said, whatever is it? What is it?
12:28He said, it's an Australopithecus.
12:33He had stumbled upon the fossilized skull of an early hominid.
12:37A landmark find.
12:39Remarkable that it was in one piece.
12:42This was Leakey's luck,
12:44and overnight, Turkana and Richard Leakey were on the map.
12:49Well, it was a very exciting discovery,
12:51and there's no question that it was a day I will always remember,
12:54because it was so unexpected,
12:56and it was so almost accidental.
12:59This spectacular skull resembled that of Xenjanthropus,
13:03found by his parents a decade before.
13:07And its age, like his parents' find, was 1.7 million years old.
13:13Identified as Australopithecus,
13:15this fossil demonstrated that some of our oldest ancestors,
13:19yet found, once roamed the shores of Turkana.
13:26Now they were intrigued.
13:28Who else lived alongside that Australopithecus?
13:32Three years would pass before that question was answered.
13:39In 1972, team member Bernard Ngenyao
13:43found some small but tantalizing fossils.
13:46Oh yes, yes, yes.
13:49That's a large piece, look at that one.
13:51The team thought the fragments were hominid,
13:54but they were anything but conclusive.
13:57We had fragments of the front of the skull,
13:59fragments of the back of the skull, fragments of the side of the skull,
14:02and when you find that, your sixth sense or experience tells you
14:06the whole skull was probably broken in one place.
14:13Over the weeks, they unearthed more fragments.
14:16And at the end of each day, Richard flew them to camp,
14:19where Meve cleaned them and pieced them together.
14:22A jigsaw puzzle like no other.
14:24It's definitely not an Australopithecus.
14:27No chance.
14:28Quite new.
14:29Yes, I think so.
14:31From 150 fragments, Meve assembled a revelation.
14:36They were looking at a hominid far more advanced
14:39than any previously found at Turkana.
14:43Dated at 1.9 million years,
14:45this hominid's brain was 30% larger than that of their earlier find,
14:50the heavy-browed Australopithecine, some referred to as Zinj.
14:56Here was validation that at least two hominids
14:59once roamed Turkana's shores at the same time.
15:04Richard asserted that this hominid belonged to a species called Homo habilis,
15:09or handyman, found elsewhere in Africa.
15:14He contended that this creature was capable of making stone tools
15:18and thus may have been our direct ancestor.
15:22True to leaky form, his bold claim caused instant controversy.
15:28Since his parents had found the first Homo habilis,
15:31Richard decided to have a word with his father.
15:35It's with some poignancy that I look back 40 years and think
15:39how I felt when we discovered Homo habilis at Lake Turkana.
15:45It was possible to get it down to Nairobi just before my father was leaving
15:48and we showed him the skull partially assembled.
15:52And he was fascinated and said to me,
15:54I agree, this is the best candidate you have for the toolmaker at Lake Turkana.
16:00And then he went off to England and a few days later he was dead.
16:04Today, 40 years later, people are still arguing about
16:07whether this is the human ancestor.
16:09They're still arguing about whether this is evidence that really
16:13it is true that humanity came out of Africa.
16:19TURKANA
16:26Turkana is the world's largest desert lake
16:29and the only way to negotiate its vast distances and rugged terrain is by flying.
16:49MEVE
16:59Meve and Louise have been exploring east of the lake.
17:03To reach headquarters on the west,
17:05the choice is either a five-day drive or a 40-minute flight.
17:10Like her father before her, Louise has become the family pilot.
17:15Today, she and Meve are bringing Richard some news.
17:18Not far from their giant buffalo excavation,
17:21the team made a key discovery.
17:24That was the first one.
17:25These were both found last week.
17:28It's a bit of tooth.
17:29This was really close to the Palerova site.
17:31It's just an incredibly rich fossil area.
17:34There are bones coming out of all of these deposits.
17:37And so, you know, the fact that hominids are there is
17:40they're very much part of what was going on.
17:43It's definitely uninterrupted and it's very small.
17:46And it's lower.
17:49It's Homo erectus.
17:51Yes, I would agree with you, actually.
17:53To the Leakeys, Homo erectus is instantly recognizable.
17:57He is the closest of our ancestors.
17:59To them, an old friend.
18:03In 1984, the team discovered a juvenile of this species.
18:07Arguably, their most momentous find.
18:11The initial discovery of Turkana boy was a fragment,
18:14a small fragment of skull that my colleague, Kamoya,
18:17picked up very close to where we were camped.
18:19We had a fairly slow start, but a few weeks we had enough
18:23to know that there was probably an awful lot more
18:25and everything we were finding from individual vertebrae
18:29to individual limb bones had never been found
18:31in association with a skull and a jaw.
18:34It was so complete.
18:36This Homo erectus discovery,
18:38the most complete early hominid skeleton ever found,
18:42was a major milestone in Richard's quest
18:44to understand our entire human story.
18:48Turkana boy is the most advanced 1.5 million year old hominid
18:53found at Turkana.
18:55His brain size, almost as large as our own.
18:59It was an individual, a young boy,
19:03at death probably standing about 5'3".
19:08We had all the neck vertebra, we had some of the ribs,
19:11we had an arm, we had the backbone, we had pelvis,
19:15part of the legs.
19:17Sadly, we didn't find his hands or his feet.
19:21He would have grown into an individual maybe 5'6".
19:26The thing about this specimen was you could begin to look
19:28at brain size to body size.
19:30It wasn't us, but it was a big advance
19:32on what lived earlier in Africa.
19:35Perhaps a brain size of a 2-year-old child today.
19:39It wasn't fully us in terms of the body, but very like us.
19:44And this indeed was the best example we have had
19:48of a real human-like ancestor 1.5 million years ago.
19:52An amazing find.
20:00After 18 years, Richard, Meeve and their team
20:04had discovered many of the players in the drama
20:07of human origins at Turkana.
20:09Beginning with the Australopithecine find,
20:12some called Zinj, then Homo habilis,
20:16followed by Turkana boy or Homo erectus.
20:20But it still isn't clear who may have begat whom.
20:25We have two potential ancestors just under 2 million years,
20:30Zinj and Homo habilis.
20:33Slightly later in time, we have Homo erectus.
20:36Now was it habilis that gave rise to erectus?
20:39Or was it Zinj that gave rise to habilis
20:42and erectus came from somewhere else?
20:45How do we organize these three skulls?
20:48That's been what's driven the research ever since then.
20:54But 3 years after finding Turkana boy,
20:58Richard reached a crossroad.
21:01In 1987, there were fewer fossils coming in.
21:05I spent most of my time struggling to justify budgets
21:09and raise money from the government and other sources.
21:12And I just got stale, and I found myself no longer enjoying life.
21:18I needed a change.
21:20Midlife crisis, you could call it. Who knows?
21:23And an opportunity came up in 1989.
21:27I left paleoanthropology and paleontology in late Turkana
21:30to work for the government in setting up a wildlife conservation program.
21:35In 1989, Richard was tapped by Kenya's president
21:39to lead the Kenya Wildlife Service,
21:42responsible for running all the national parks and game reserves.
21:47At the time, it was bankrupt and facing a serious threat.
21:51Kenya's elephants were being slaughtered at an alarming rate,
21:56killed for their ivory tusks, prized for jewelry and decoration.
22:01Already 85% of Africa's elephants had been decimated,
22:06with poachers brazenly operating throughout Kenya's parks.
22:11I am going to do my level best to eliminate the elephant poachers.
22:18It was a tough nut to crack, given the high value of ivory,
22:22and it seemed to me we needed publicity.
22:25To buy the sort of publicity we needed would have been beyond our means.
22:29We needed tens of millions of dollars.
22:34With trademark boldness, Richard came up with a plan
22:38to burn millions of dollars of seized ivory in one giant bonfire.
22:46It was a masterstroke.
22:48There was worldwide publicity,
22:50and practically overnight, the ivory market dried up.
22:54Within three months of burning it, the ivory price was down to $5 a pound,
22:59a drop of $145 per pound in three months.
23:06It worked.
23:08Richard's audacious stunt inspired the world.
23:11People rallied in support of the elephant.
23:14Donations poured in.
23:16But in other circles, Richard ignited a firestorm.
23:20There were pressures on me to allow things to be done
23:23in a way that wouldn't have worked,
23:25but would certainly have generated income for public officials.
23:29And my response was simply no.
23:31That's not what I raised the money for.
23:33And this, for certain, generated a great deal of resentment
23:37amongst certain people who felt that I was somehow setting a new set of rules up,
23:41which was not helpful to their private aspirations to get rich on public funds.
23:47But that's not what I took the job for.
23:50His uncompromising anti-corruption stance was not popular
23:54among those accustomed to dipping into government coffers.
23:59His enemies turned the public against him.
24:03I used to get a lot of death threats.
24:05I mean, hardly a week would go by without some form of death threat.
24:10And it was during that episode that I took a flight in an airplane.
24:14I was a pilot. I flew my own plane.
24:16And the plane lost power and I had to put it down in an emergency situation
24:21in a country that you wouldn't normally choose to land a plane in.
24:25And in the course of responding to gravity without an engine
24:30and bringing a fast-moving plane to a stop,
24:35the engine came off the plane and pushed back into my legs
24:39and broke both of my legs below the knee in such a way that they had to be amputated.
24:46The plane had somehow run out of gas,
24:49even though Richard had taken off with a full tank just ten minutes before.
24:54It was all very puzzling.
24:58The big question was, was this a simple accident or was this an attempted assassination?
25:05Well, it would be tempting to say, oh yeah, those mean people tried to kill me.
25:09They probably did, but I'm not sure.
25:11And it may well have been an attempted assassination.
25:14But it failed and, you know, it's never fun to talk about failure.
25:23Undaunted, Richard returned to work, but his enemies did not give up.
25:28And I just had enough. I just said, fine, let me out of here.
25:31I resigned and quit, finished.
25:34I have given the best years of my life to public service
25:37and I recently gave my legs as well.
25:40Under these circumstances, I have today sent a letter to His Excellency the President
25:45offering my resignation.
25:48Still determined to have an impact, Richard became a politician.
25:53He then held high office in the Kenyan government.
25:56But his candor was not an asset.
26:01After three years, he left the public arena to return to his life's passion,
26:06the search for man's beginnings at Turkana.
26:11With renewed purpose, he founded the Turkana Basin Institute,
26:15dedicated to the study of human origins
26:18and built, not surprisingly, on the ancient shores of Lake Turkana.
26:41The Leakeys and their team had found evidence of several types of hominid ancestors,
26:47stretching back nearly two million years.
26:51But which of them were members of our human family?
26:55And how could they prove it?
26:59Their new quest?
27:02To find out.
27:10To find in the bones of Turkana evidence of the traits that make us human.
27:17Traits that ground us and bring us home.
27:22All of humanity shares many common traits.
27:25They came into existence at different times,
27:28but they're all connected with us being what we are today.
27:31I think the best way to show our relationship with these ancient fossils
27:35is to start now and walk backwards in time, like an onion.
27:39Let's peel off the skin from the outside and go to the core.
27:44So what are the basic traits that make us human?
27:48Language, our most definitive trait.
27:51Surely the hominids who first used language are related to us.
27:57Toolmaking.
27:59Who were the first toolmakers who conceived the first tools?
28:03They too might be our ancestors.
28:06And farther back, walking upright.
28:09Who was it who took those first tentative steps towards humanity?
28:15Language, toolmaking, walking upright.
28:20We need to find the traits that bind us all together
28:24as a common species with a common origin.
28:32The hunt for traits was on.
28:35Today, Richard has gathered a dream team of scientists of many disciplines,
28:40all members of the Turkana Basin Institute.
28:45His aim is to pinpoint when these critical human traits arose.
28:51But how would it be possible to find evidence of a trait like language,
28:55which leaves no trail in the fossil record?
28:59You would have to search for the speakers, not the speech.
29:06Genetic and archaeological evidence point to an epic behavioral change
29:11around 70,000 years ago.
29:15It was wanderlust on a grand scale.
29:19It was then, many experts believe,
29:21that we began migrating out of Africa into the far reaches of our planet.
29:26Some also believe that language was a critical factor in that migration.
29:33Today, on the west side of Turkana, along the ancient lakeshore,
29:37a Cambridge University team is looking for traces of people
29:41from the time of those first great journeys.
29:46Okay, we are recording humans, harpoons,
29:52interesting lithics, if we find, and identifiable fragments of fauna.
29:58And Rob and I walk first, yeah?
30:03Anthropologists Marta Lahr and her husband, Robert Foley,
30:07prospect here every year with their international team
30:10in an area rich with fossils.
30:15This team is incredibly skilled at discerning the difference
30:18between the remains of ancient humans and all the rest.
30:24This man has some eyes.
30:28So, this is a fragment of human cranium.
30:32You can see a piece of the suture.
30:35Yeah, a part of the mastoid. It is a mastoid.
30:40Marta is on a quest that has one ultimate prize,
30:44human fossils from the critical period of migration.
30:4970,000, 75,000, that's my dream.
30:54Somewhere in this country, 70 to 75,000 years ago,
30:58lie the remains of a generation of humans
31:01who may have taken the very first steps out of Africa to populate the earth.
31:09Were these early modern humans already speaking a complex language?
31:13And how could we prove that?
31:17Recent language studies have explored the many building block sounds
31:20that make up all languages.
31:23These sounds are most numerous in African languages.
31:28And according to a new theory on the origin of languages,
31:31that diversity of sounds suggests that language originated here.
31:37What would account for this diversity?
31:40Rob and Marta's work may provide a partial answer.
31:44There was a moment, quite early in the history of humans,
31:48when humans spread throughout Africa.
31:54Climate and geologic data suggest that over thousands of years,
31:58harsh environmental conditions and drought
32:01isolated distinct populations within Africa.
32:05This may explain Africa's extraordinary genetic diversity.
32:10Could that also be a factor in Africa's linguistic diversity?
32:16This fundamental human trait, language, may have been mastered here.
32:21And if it was, when did that happen?
32:25There is some evidence that complex languages began to flourish
32:29just when our ancestors were undertaking the most daunting of all journeys.
32:35And that's when it's happening, 70, 75, 80,000 years ago.
32:40And I want to see them. I want to know what they look like.
32:53Found more fish?
32:55Well, there's plenty of that.
32:57And a piece of hippo.
32:59Come!
33:01Oh, wow.
33:06There it is.
33:08So we'll try to stop grinning for a minute.
33:12Let's look.
33:14So this is very exciting.
33:17So let's have a look at it.
33:21It's extremely small.
33:24So, I don't have an enormous jaw.
33:29But that's the edge of my jaw there.
33:32So we put it at the edge of my jaw.
33:35Look.
33:36And that is already the edge of the chin there.
33:39So extremely small.
33:41It's a lady.
33:44But very little worse.
33:46A young, a late teenager.
33:49Yeah, a young woman.
33:52Marta later concluded that this teenager died only 10,000 years ago,
33:57long after the time of the Great Migration.
34:01While she tells a poignant story all by herself,
34:04her ancestor's tale is the one that will be the prize.
34:09So for Marta, the search will continue.
34:12Could Robin Marta find the people who first spoke a language
34:16that could be traced into the modern times?
34:19Probably.
34:23Without a language, it would have been exceedingly difficult
34:27to colonize the world as rapidly as it happened.
34:32I think the development of speech as we know it today,
34:35syntactic speech, has to have been a major event,
34:38and the favored location for this is eastern Central Africa,
34:41which is where we are at Lake Turkana, where we are today.
34:58Richard is curious about his own trajectory out of Africa,
35:02and now he has a way to trace it.
35:05He's taking a sample of his DNA to send to the Genographic Project,
35:10a genetic mapping initiative which will reveal his deep ancestral past.
35:15I'm intrigued. Who were these people at that end of my line?
35:19In other words, where the line starts in Africa, who were they?
35:24I'm really looking forward to seeing these results. It fascinates me.
35:29It is only through complex technology
35:32that Richard's genetic journey out of Africa can be traced.
35:38Fittingly, scientists at Turkana are searching for evidence
35:41of the birth of technology,
35:43clues to the first toolmaker to walk the earth.
35:54It is, indeed, the birth of technology. We can really say that.
35:59Toby, you have seen those little flakes there? All those ones?
36:03Archaeologist Helene Roche has spent two decades in Turkana,
36:07unearthing evidence of another definitive human trait.
36:12She and her team face a challenge.
36:15How to get inside the toolmaker's head?
36:19Obviously, there was something in mind.
36:21They have the image or the thought of what action they should do
36:26with their hands in order to be able to detach a piece,
36:31a small piece of raw material from the block they were mapping.
36:35And you cannot do that without a goal, an aim,
36:39or a thought about what you are doing.
36:41But how could she prove the toolmaker's intent?
36:45Clues in the form of sharp stone flakes
36:48can be found in beds on the west side of the lake.
36:51It's extremely rich and you have patches of flakes in different places
36:56and then you have quite a lot of bones as well.
36:59And so we do think that it's a place where they have done a lot of flaking
37:06and probably very likely butchering as well
37:11because you have all these bones which are together with the stones
37:15which have been flaked.
37:18OK, Leo, ready? Give me another piece.
37:21Sonia Armand, an archaeologist,
37:24has found that the toolmaker was a shrewd craftsman.
37:28What we know about the Hominids here in this region
37:31is that they didn't walk too far to collect their raw material.
37:36We are not saying they were lazy.
37:38We are saying they were clever.
37:42Sonia has discovered that the toolmaker was a geologist of sorts,
37:46a surprisingly sophisticated judge of raw material.
37:51This is a very good, very fine grain raw material
37:55and you can see how sharp are the edges
37:58even after more than one million years inside the sediment.
38:03Definitely we have a selection of different raw materials
38:06according to maybe different activities and tasks.
38:12If we go back in time from the present to the distant past,
38:15the ability to make things is very important.
38:19And the stone tool record is absolutely critical
38:22to understanding the breadth and scope of the human experience.
38:29But who was the first toolmaker?
38:33Fossil evidence shows that the species known as Homo habilis
38:37was walking the shores of Lake Turkana 1.9 million years ago,
38:41the same date as some of the oldest beds Helene has excavated.
38:46Then in 1994, she started working sediments far older.
38:51She and her team slowly started to uncover evidence
38:54of one of the oldest stone tools ever found.
38:58Perhaps this too was the work of habilis.
39:02They painstakingly recovered 70 pieces of stone
39:06that had been chipped away from a single cobble.
39:10Then they put them back together again,
39:12but one piece was missing.
39:16It was in fact what had been in the toolmaker's mind,
39:19a sharp-edged tool 2.3 million years old.
39:24This suggests that a mind that is capable of seeing things
39:27that aren't yet there, it's just a complex mind,
39:30a mind that has cognitive skills.
39:32I think it's fundamental because it adds a trait,
39:35it adds evidence of another aspect of being human.
39:41Every new find opens a window into the toolmaker's mind,
39:45and we invariably see a glimmer of ourselves.
39:50It's a very emotional activity to dig and excavate and record
39:55because you know that you are the first one after the hominid
39:59to touch something and take something in your hand.
40:03And it's something that is part of the beauty of that job, of course.
40:21But what human traits came before toolmaking?
40:26Travelling even further back,
40:28can we find traces of the most fundamental human trait,
40:31a trait that first defined us as human?
40:34Walking on two legs with the hands free to carry, perhaps to throw,
40:38that adaptation to standing upright
40:41and constantly walking on two legs as opposed to four
40:45was very central to the human story.
40:48But the origins of this critical human trait
40:51had never been found at Turkana.
40:54Did this stage of our evolution only happen elsewhere?
40:59In 1995, we had had a lot of bad luck with finding hominids.
41:04And so the field crew were just beginning to wonder
41:07whether they had actually lost their knack.
41:10And then this jaw turned up, and suddenly there was a potential there
41:14to find more fossils, more human ancestors.
41:17First we found the upper jaw, and then we found some isolated teeth,
41:22and then we found this mandible.
41:25And there was this most spectacular row of teeth
41:28from both sides of the mandible, just protruding out of the stones.
41:32I mean, it was just fantastic.
41:34They called this find Australopithecus anamensis.
41:38But the story was incomplete.
41:41As important as the jaw was to confirming a new hominid,
41:45without evidence of the lower body,
41:47they couldn't determine whether he walked on four or two legs.
41:51But further excavation gave them the answer.
41:56In addition to the lower jaw and fragments of a skull,
41:59the anamensis discoveries included elements of the lower leg.
42:04We have a tibia, a very good specimen
42:07where you can look at details of the knee joint.
42:10The tibia that we found is very, very modern-looking,
42:14from the shape of the top end and the bottom end.
42:17Anamensis is definitely a biped,
42:19and I don't think anybody has disputed that.
42:21It's very clear.
42:23Nobody questions that tibia.
42:26A rarity for ancient finds, anamensis was very clearly dated.
42:31There were two volcanic ashes,
42:33and then most of the fossils come from between the two.
42:35So the date is very good and very clear,
42:38and it's just less than 4.2 million years.
42:42So to have a tibia, a very clearly bipedal tibia,
42:46over 4 million, 4.2,
42:49was taking back bipedality by a significant amount of time,
42:53half a million years.
42:55Anamensis is a milestone,
42:58the very earliest hominid yet discovered
43:01that scientists widely agree walked upright.
43:05Bipedalism, walking on two legs,
43:08the first defining marker of our lineage.
43:12With the development of upright posture,
43:14coming out of the forest, did it happen quickly?
43:18Was it related to gathering food?
43:21Was it related to security?
43:24Why would a creature successful on all fours
43:27choose to stand up on its hind legs to walk?
43:31Geochemist Turi Serling thinks he has found the answer.
43:36One of the things that we can do at Turkana
43:39is because the dating is so good
43:41and people have been collecting fossils for so many years,
43:44we can go there and interrogate the fossils, as it were,
43:48and ask them, what is it that you are eating?
43:52We can see if these animals were primarily eating these grasses
43:57or were they primarily eating these trees and shrubs.
44:02Turi Serling studies ancient teeth.
44:06Chemicals found in teeth can identify what a creature ate
44:10and where it lived.
44:12With enough samples, he can track the course of changing landscapes
44:16and how creatures living in them changed as well.
44:19One of the fascinating things to me about this whole big story
44:24is that at 10 million years ago,
44:27this was a completely different world than anything that we know today.
44:32Somewhere between 6 and 10 million years ago,
44:35the grasses just took off all over the world.
44:39Serling's work suggests our ancestors were caught in that transition
44:43and forced to adapt.
44:47And as this landscape opened up from a dense forest
44:52to this open environment, this is where we evolved.
44:57Perhaps pushed by environmental forces,
45:00some predecessor of Anamensis stood up on two legs
45:04and walked out of the forest in the direction of the modern world.
45:10There was a new ecological opportunity.
45:12The forests were thinning out from a very closed canopy
45:16where large primates moved from treetop to treetop
45:20to a more open canopy where large primates
45:22had to come down from the tree to get to the next one.
45:25It was the exploitation of that new habitat
45:29that led to us becoming humans.
45:33With the discovery of Anamensis,
45:35Richard Leakey now has a possible narrative
45:38of how we evolved going back 4 million years.
45:43It was over 40 years ago that I first came to Turkana
45:46and began my work.
45:48Since then, my family members, Meve, now Louise,
45:51and many colleagues have had tremendous success
45:54in the work that we've done here.
45:56We can go from the present to ancestors of modern people,
45:59the very earliest of which are about 200,000 years old.
46:02We can go to their ancestors of Homo erectus.
46:05We can go from Homo erectus to their ancestors,
46:08back around to with Homo habilis.
46:10And we can go even further back to what is probably
46:13one of the ancestors of everything that we're seeing
46:16along this line leading to the present.
46:19We're not absolutely sure about the far end.
46:21More needs to be found.
46:23The Anamensis story is far from complete.
46:26The Homo sapiens end looks remarkably complete,
46:29and most of us are comfortable with it.
46:31But what was going on around 65,000 years ago
46:34when presumably speech and we first came into existence
46:37in the form we are today?
46:39These questions can be answered,
46:41but irrespective of what we still don't know,
46:44the one thing we do know is that all of us are African.
46:57The phenomenal discoveries at Turkana have only been possible
47:01through an alliance with the people who call this land home.
47:05You can't be an island in a sea of people.
47:08You have to be very much a part of what's going on.
47:12These people here are the custodians
47:16of some extremely important global heritage.
47:27To Richard Leakey, the people of the lake today
47:31are just as vital as those who have come before.
47:35He believes the search for our origins must benefit them
47:39just as it does him.
47:42Since the water of Lake Turkana is alkaline,
47:45the Leakey team provides
47:48They've also helped to create a market garden,
47:51run entirely by the local women
47:54for the first time giving them a stake in the local economy.
47:58This is our market garden.
48:01This is our market garden.
48:04This is our market garden.
48:07This is our market garden.
48:10This is our market garden.
48:13This is our market garden.
48:24But perhaps the most vital connection
48:27is to the children of Turkana.
48:29For them, the institute supports health clinics
48:32and schools on both sides of the lake.
48:35These kids are the future here.
48:37There's nowhere else in Kenya that has these fossil deposits.
48:41And so really, if they can understand the significance
48:44and be involved and have a real stake in protecting it,
48:48then I think we've really put something back into this region
48:52that's very significant.
49:00Good.
49:03Isn't that right?
49:07Here in Africa is where we began.
49:11Walking on two legs, making stone tools,
49:15and being able to talk about it.
49:18But is that all there is to being human?
49:22Isn't there something more?
49:27Intriguingly, a fossil discovered in the 1980s
49:31has recently revealed one final fugitive trait.
49:36I think one of the more interesting things about Turkana boy,
49:39and we've still got a lot to learn,
49:41is that it was an individual who died with disease,
49:44fairly far advanced, bone disease.
49:47And he had a spine that looks like it had deformities.
49:51He wasn't a fully functioning, robust,
49:55shortly to be a teenager type.
49:58He was probably a person who needed a lot of help.
50:02With such a deformity, Turkana boy
50:05would surely have been vulnerable to predators,
50:08unable to hunt or even collect food.
50:11Were it not for one very special trait,
50:14he might never have survived.
50:17Bipedalism carried with it an enormous price
50:20where compassion was what you paid your ticket with.
50:23You simply can't abandon somebody who's incapacitated
50:27because the rest will abandon you
50:30next time it comes to be your turn.
50:33A trait called compassion.
50:36Understanding someone else's suffering
50:38and seeking to alleviate it.
50:44For me personally, it was an interesting reflection.
50:47Obviously, when you have two good legs,
50:49you don't think about their value,
50:51but when you have your legs amputated after an accident, as I did,
50:55you suddenly recognize that without legs
50:57you are totally dependent on other people.
51:00One leg doesn't get you anywhere either.
51:02You have to have both if you're going to self-propel
51:05and so I believe behaviorally there was a premium put on bonding,
51:10care, love, affection and protection,
51:14all which you could encompass in the word compassion.
51:20Another distinctly human trait is our intrigue with the past,
51:24our desire to understand who we are and where we came from.
51:30Today, Richard will receive the results from the DNA sample
51:33he sent to the Genographic Project.
51:36To no one's surprise,
51:38Richard's ancestors were in the vanguard of those
51:42setting out to find new lands.
51:44It looks like I'm starting out somewhere near where I live today,
51:48at Lake Turkana.
51:51But it seems to have gone across what is today the Middle East,
51:54up through Asia Minor, as it used to be called,
51:57around the southern part of Europe,
51:59then across into Spain, France and up and then it split,
52:03some going to Scandinavia and some ending up in England.
52:08To look at a map like this,
52:10which confirms why I feel so at home at home,
52:13and I'm a fourth generation Kenyan,
52:16I feel very good there and this actually makes it very clear
52:20why my genes are at ease in my own homeland.
52:30Richard Leakey has spent most of his life in his homeland
52:34at the forefront of the search for our ancestors.
52:38For all who work here, the search has been scientific,
52:42but also deeply personal.
52:44I don't think that you can search for human origins
52:47if you are not, in a way, looking at your own personal story.
52:52Yeah, it's broken here just before the chin.
52:55Isn't it lovely?
52:56Isn't it lovely?
52:57I mean, every time that you find a piece of a person, it is a person.
53:02The mouth was large or small,
53:04so you can't begin to imagine their faces and their sizes
53:08and so it is exciting every time, every time.
53:16On the exhilarating frontier of prehistory at Turkana,
53:20there is still much to discover.
53:23I like to be a little bit open about it
53:25because I always think I'm going to find another fossil tomorrow
53:27that's going to completely upset everything.
53:30And the Leakeys believe if the answers are anywhere, they are here.
53:36You have an incredible fossil record with thousands and thousands of specimens
53:40that each are pieces of this big puzzle
53:43that's really spectacular and really beautiful.
53:48Turkana tells us that the forces of change are constant
53:54and that we are all creatures of change, adaptable and resilient.
54:04Across the millions of years, our epic story lies buried aside this lake.
54:15So, when we encounter the bones of Turkana,
54:18they will look familiar.
54:20They are...
54:24They were all made to be.
54:27We can find them.
54:29They were all made to be.
54:31They were all made to be.
54:33We can find them.
54:35They are the bodies of the sisters
54:38that we have been searching for
54:40through the history of our history
54:42and through the faces and the skin.
54:45We can show them as pieces of what our home is today.
54:49We can show them as pieces of what our home is today.
55:08Joseph's face was black as night
55:14and the pale yellow moon shone in his eyes.
55:20His path was marked by the stars in the southern hemisphere
55:26and he walked his days under Africa's skies.
55:34This is the story of how we begin to remember.