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Le berceau africain
Les plus anciens membres de l'espèce homo sapiens ont été découverts en Afrique de l'Ouest. Des recherches récentes suggèrent pourtant que les hommes modernes seraient apparus simultanément dans plusieurs régions d'Afrique. En outre, ils auraient continué de se reproduire avec d'autres sous-espèces d'Homo, amplifiant leur diversité génétique. Homo sapiens serait donc une espèce hybride.
Les plus anciens membres de l'espèce homo sapiens ont été découverts en Afrique de l'Ouest. Des recherches récentes suggèrent pourtant que les hommes modernes seraient apparus simultanément dans plusieurs régions d'Afrique. En outre, ils auraient continué de se reproduire avec d'autres sous-espèces d'Homo, amplifiant leur diversité génétique. Homo sapiens serait donc une espèce hybride.
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TVTranscription
00:02200,000 years ago, a new species emerged on Earth.
00:09Homo sapiens. Modern man. Us.
00:17Today, we are 7 billion, scattered across the entire planet.
00:24We are going to tell you the story of our journey from one continent to another.
00:28You explain how we crossed Asia, reached Australia, populated Europe and finally the Americas.
00:38This journey began where we were born, in the cradle of humanity, in Africa.
00:46When our species appeared, archaic human groups still populated the continent.
00:55What role did they play in our evolution?
01:01We thought we had never been in contact with them.
01:04But recent discoveries tell us a completely different story today.
01:11This sample is proof that humanity appeared much earlier than scientists have thought.
01:16years.
01:19Since variation is the driving force of evolution, this explains why hybridization is such a powerful evolutionary force.
01:27Our history is the history of many human groups.
01:30It is the one of diversity.
01:33In light of the new discoveries,
01:36Scientists are reviewing theories about the origin of our species.
01:40Because we are not who we thought we were.
02:04East Africa, 195,000 years ago.
02:13These hunters in the savannah have the same body as us.
02:18The same brain.
02:24Archaeologists have named this man Homo I.
02:31He died before he was 30 years old.
02:36But the echo of his death has reached us.
02:39Because he is the first known member of our species.
02:50He is one of us.
03:13Homo I lived here.
03:16If the valley of Homo is arid today,
03:19195,000 years ago,
03:21It was a marshy land with lush vegetation
03:25offered an ideal habitat for prehistoric man.
03:34Two American scientists are very familiar with the region.
03:39Anthropologist John Fliegel
03:41and the archaeologist John Shane.
03:48They have been coming here for 15 years.
03:50walking in the footsteps of the discoverers of our ancestor Homo I.
04:07In 1967,
04:09An international expedition has been sent to southern Ethiopia
04:13searching for human fossils.
04:16And the archaeologists did indeed unearth
04:19the remains of three prehistoric men.
04:29The most complete skeleton
04:30was called Homo I.
04:35At the time,
04:37no technique yet allowed
04:38to determine his age.
04:42For about thirty years,
04:44Homo I was merely a fossil.
04:46who was waiting for his story to be discovered.
04:50Everything changed in the early 2000s.
04:53when John Fliegel and John Shane
04:55have resumed excavations in Ethiopia.
05:02We're here.
05:04The lost world.
05:06It's spectacular.
05:09The big question was then
05:11When did modern humans appear in Africa?
05:14The age of the discovered skeletons was unknown.
05:17However, everything suggested that they were very old.
05:23Some said they probably had
05:2420,000 or 30,000 years.
05:28We even went so far as to say
05:29that they might even have been 100,000 years old.
05:33The mystery had to be solved.
05:41The bones are too old
05:42to make carbon-14 dating possible.
05:45A technique that does not allow one to go back
05:48beyond 50,000 years.
05:51On the other hand,
05:52thanks to the determination of the content
05:54in argon from the sediments,
05:56scientists were able to date
05:58the formation of the relief.
06:04It was thus established
06:05that the layer of sediment
06:07containing the skeleton of Homo 1
06:09was 195,000 years old.
06:17This figure astonished us.
06:20We had never thought
06:22that this fossil could be that old.
06:27The human family tree
06:29dates back 2.5 million years.
06:32Before, we looked more like each other
06:34to monkeys rather than to men.
06:41The countless ramifications
06:42which have developed over time
06:45correspond to as many species
06:46with strange names.
06:51Species
06:52all of which have been classified
06:54as archaic
06:54by anthropologists.
06:58What distinguishes Homo 1,
07:00that's precisely it,
07:02is a modern man,
07:03a member of our species,
07:06a Homo sapiens.
07:15Homo 1 was also tall
07:17than a present-day African
07:18and weighed 70 kilos.
07:20He hunted wild boar
07:22and the antelope.
07:27But one day,
07:28Homo 1 was no longer able
07:30to hunt.
07:34No clues show
07:36that his remains have been moved
07:37or buried.
07:41For 195,000 years,
07:43It never moved from its place.
07:53The only thing we are
07:54absolutely certain
07:55Regarding Homo 1,
07:57that's precisely why he died
07:59at this location.
08:05He was supposed to be lying down
08:07somewhere secluded,
08:09surrounded by his loved ones,
08:10his wife, his children,
08:12his best friends,
08:13his brothers and sisters.
08:17We had to take care of him
08:19and try to relieve his suffering.
08:28or,
08:29as often happened
08:30among hunter-gatherers,
08:31He was left there.
08:34Not out of cruelty,
08:36But because it was the custom.
08:38When someone couldn't
08:39follow the group,
08:40They gave him food,
08:41attention was paid to his comfort
08:42and we abandoned it.
08:46That's life.
09:00Over the years,
09:02John Shea collected
09:03number of lifestyle indicators
09:05inhabitants of the Homo valley.
09:12It's under the acacia trees
09:14that we make the best discoveries.
09:17And he is impressed
09:18by the ingenuity of these men.
09:21It is a stone tool.
09:22These traces must have been made
09:24by a striker.
09:26Such objects do not exist
09:27in its natural state.
09:29Great.
09:34These people manufactured everything,
09:36from tiny rooms
09:38up to this kind of large tool.
09:44a large number of objects
09:45indicate a manufacturing site.
09:48These isolated rooms
09:49perhaps they simply
09:50were left there,
09:51on the trail.
09:52We know we'll be back
09:53and if we ever need
09:55of a cutting tool,
09:56We'll find one here.
10:00It was the distributor
10:02automatic of the time.
10:04Just like today,
10:05no traffic
10:06with bundles of banknotes.
10:07but neither did they
10:08did not need
10:08to take on the task of carrying large stones.
10:10There were tools everywhere.
10:15They were payment cards
10:16from prehistory.
10:24These people were like us.
10:27They had a sense of humor.
10:28felt sadness,
10:30joy.
10:33We have no reason to think
10:35that their emotions,
10:35their intellect,
10:37were different from ours.
10:39No anatomical clues
10:40or archaeological
10:41doesn't allow us to say.
10:43Everything that drives us
10:44it's as if these people
10:45were simple-minded
10:45that's just a legend.
10:47from the idea that what is old
10:48is primitive
10:49and that which is primitive
10:50is backward.
10:54These people survived
10:55thanks to their intelligence.
10:57They were thinking,
10:58were planning
10:59and obviously,
11:00They succeeded
11:01since they have always
11:02a lineage, us.
11:06The bones of Homo 1
11:08seem to indicate
11:10that of East Africa
11:10is the cradle
11:11of our species
11:13our Garden of Eden.
11:26According to the prevailing theory,
11:29modern man would have appeared
11:31in this region of the world
11:32about 200,000 years ago.
11:35And from there,
11:36it would have been sown
11:37across the continent,
11:38then across the entire planet.
11:41That's a hypothesis.
11:42what now come
11:43to support the DNA analyses.
11:50In the 1980s,
11:52geneticists
11:53have indeed discovered
11:54that the mitochondria
11:55allowed to go back
11:56the human lineage.
11:59Mitochondria
12:00are located outside
12:01from the nucleus of our cells,
12:03which they ensure
12:04energy production.
12:08Each one contains
12:09a DNA molecule
12:10which is only
12:11transmitted by sea.
12:16We weren't used to it.
12:17to consider
12:18that the research
12:18on DNA
12:19could apply
12:20in the field of evolution,
12:21of anthropology,
12:22of the origin of man.
12:25It was new
12:26spend
12:26that they could
12:27complete the study
12:27fossils
12:28in order to determine
12:29when and where
12:30The man appeared.
12:37As the transmissions progressed,
12:39mitochondrial DNA
12:41is undergoing changes.
12:44That's by counting
12:45the number
12:45of these mutations
12:46that it was possible
12:47to determine
12:48the era
12:48where all the women
12:49of the planet
12:50had
12:50a common ancestor.
13:03This one
13:04would have lived
13:05in Africa
13:05there are approximately
13:06200,000 years,
13:07so approximately
13:08at the same time
13:09than Homo 1.
13:16He was given
13:17the name
13:17of mitochondrial Eve.
13:22She is our
13:23common ancestor
13:24the most recent one.
13:25She had a mother,
13:26Of course,
13:27which is therefore also
13:28our common ancestor
13:29to all.
13:29But that goes back
13:30further on.
13:32Mitochondrial Eve
13:33is our ancestor
13:33municipality
13:34the most recent one.
13:38Geneticists
13:39adopted
13:40the same approach
13:41with the Y chromosome,
13:42who is, in turn,
13:44exclusively
13:45passed down from the fathers.
13:51The common ancestor
13:52the most recent
13:53of all men
13:53populating today
13:54the planet
13:55also lived
13:56in Africa.
14:02We called him
14:03Adam Y chromosome.
14:09If our Adam and Eve
14:11genetics
14:11They didn't know each other.
14:13on the other hand,
14:14they tell us
14:14The same story.
14:17We can conclude
14:19that we share
14:19an African origin
14:20a very recent municipality.
14:22And so,
14:23that the differences
14:24also obvious
14:24skin color
14:25and hair
14:26are very recent
14:27and rather superficial.
14:31It has become
14:32a banality
14:32to say
14:33that we are
14:33a young species
14:34and that we are
14:36all from
14:36from a single household.
14:42Our genes
14:43and our skeleton
14:44we learn
14:45Indeed
14:45that this home
14:46is located
14:46in East Africa
14:47and that there is no
14:49than for the last 200,000 years.
14:52That's the theory.
14:54Is she
14:54However
14:55Absolutely accurate?
14:57The story
14:58of our creation
14:59is perhaps
14:59Not that simple.
15:13The Max Planck Institute
15:14is one of the largest
15:15research centers
15:16of the world
15:16on the evolution
15:17of man.
15:23Thanks to their modeling
15:25in 3D by scanning,
15:26fossils
15:27they are studied there
15:28even in
15:29the tiniest
15:29details.
15:38This skull
15:39was discovered
15:40in Africa
15:41on the site
15:42from Jebeliroud.
15:45It is 300,000 years old
15:46that is 100,000
15:48moreover
15:48than in word 1.
15:53It belonged
15:55to a human
15:55archaic
15:56strangely endowed
15:57of certain traits
15:58modern.
16:06The face
16:07is small
16:08while the skull
16:10is primitive.
16:11That's very interesting.
16:15So far,
16:16the theory
16:17was that the brain
16:18and the face
16:19evolved simultaneously.
16:21Gold,
16:21this is clearly not
16:22Not the case.
16:23Here,
16:23we have a face
16:24modern associate
16:25to a brain
16:26primitive.
16:31This combination
16:32surprising
16:33done
16:33of man
16:34from Jebeliroud
16:35our predecessor.
16:39A man
16:40modern
16:40in the making.
16:44However,
16:45there is something even more surprising
16:45Again,
16:47its place of origin.
16:49The Jebeliroud site
16:51is not found
16:52in Ethiopia,
16:53but 5000 kilometers away
16:55From there,
16:55in Morocco,
16:56on the other side
16:58from Africa.
17:02How is this possible?
17:03that this precursor
17:04of our species
17:05lived so far away
17:06of our place
17:07of supposed birth?
17:09Perhaps finally
17:11there is not one
17:11but several outbreaks
17:12of origin
17:13and that each group
17:15contributed
17:15to our evolution.
17:22The emergence of a species
17:23is still a phenomenon
17:24complex and poorly understood.
17:33The discovery of this fossil
17:35in Morocco
17:35we learn
17:36that the appearance
17:37of modern man
17:37was done
17:38in different places
17:39from the African continent.
17:42In North Africa,
17:43SO,
17:44but also in South Africa
17:45and in East Africa.
17:49All these populations
17:50have developed
17:51over thousands of years
17:52a skull shape
17:53which is their own
17:56and all contributed
17:57in multiple ways
17:58to the current diversity.
18:04The different anatomical features
18:06of modern man
18:06They may have evolved separately.
18:10The skull
18:11is more rounded
18:12in such region,
18:14the higher forehead
18:15in another one.
18:16and the jaw
18:17even smaller elsewhere.
18:21But then,
18:22how these characteristics
18:23have they merged
18:24to shape modern man?
18:37At the time of the appearance
18:39of our species
18:40different human groups
18:41should,
18:42one way or another,
18:43to be in contact.
18:48their members
18:49perhaps
18:50met
18:50and coupled,
18:52exchanging
18:52their genes.
18:54That's the hypothesis
18:55defended
18:56by the anthropologist
18:57John Hawks.
19:01John Hawks
19:02is convinced
19:03than social networks
19:04extended
19:04across the entire continent.
19:08it was enough
19:09that each group
19:10either in contact
19:11with his neighbor
19:11so that the link
19:12be maintained
19:13across vast territories.
19:24throughout Africa,
19:26the archaeologists
19:27discovered
19:27this type of shell.
19:29This one belongs
19:30to the species
19:31Nassarius
19:31and it is perforated
19:33because it was worn
19:34in jewelry
19:34on a wire.
19:37We found some
19:38in North Africa,
19:39in South Africa
19:40and in Israel.
19:40to thousands
19:42kilometers
19:42distance,
19:43seashells,
19:44the technique
19:45and the intention
19:45are the same.
19:50Everyone
19:51can pick up
19:51a seashell
19:52and to take an interest in it.
19:55But think
19:56in the manner
19:56to pierce it
19:57and to wear it
19:58and thus create
19:59a sign
20:00that relates
20:01of a concept
20:02very specific.
20:06This broadcast
20:07ideas
20:07over long distances
20:08seems to indicate
20:09that the groups
20:10were travelling
20:10of a territory
20:11to the other.
20:14The ideas
20:15circulating
20:15and genes
20:16Also.
20:19Because
20:19when humans
20:20come into contact
20:21with each other,
20:23They mate,
20:24They have children.
20:32The populations
20:33mix together.
20:37That's how it is
20:38that groups
20:39very different,
20:39in their appearance
20:41and their way
20:41to act,
20:42have merged
20:43gradually
20:44in a single community
20:45which is called
20:45modern men.
20:55Over the millennia,
20:57significant climate variations
20:59affected
21:00travel
21:01prehistoric men.
21:04In France.
21:04During difficult times,
21:06Africa
21:06was so dry
21:07that the Sahara
21:08it was becoming a barrier
21:09impassable.
21:12But when the climate
21:13was becoming more lenient,
21:15deserts
21:16disappeared.
21:21A trait of adaptation
21:23which appeared somewhere
21:24could then spread
21:25anywhere else
21:26on the continent
21:27just as easily
21:29that the technique
21:29drilling
21:30seashells.
21:36Just recently,
21:37many archaeologists
21:38and anthropologists
21:39were looking for a home
21:40of unique origin,
21:41a kind of Garden of Eden
21:43which would explain
21:44why do we look alike
21:45all.
21:47We now know
21:49that this scenario is false.
21:51In my opinion,
21:52our origins
21:52look more
21:53to that.
21:57River water
21:58who makes his way
21:59his own path.
22:00Sometimes,
22:01the current splits
22:02then it reforms,
22:03but the flow
22:04is uninterrupted.
22:07The origins
22:08of modern man,
22:08It's the same.
22:10Our story
22:10is that
22:11numerous human groups.
22:12She is the one
22:13of diversity.
22:18According to this hypothesis,
22:19we are a species
22:21born to many parents
22:22scattered
22:22throughout Africa.
22:29Our roots
22:30are much more intertwined
22:31that we couldn't have imagined.
22:49our story
22:50takes a turn
22:50even more fascinating
22:52thanks to research
22:53from the genealogist
22:54African American
22:54Jacqueline Johnson.
23:03This scientist
23:04is passionate
23:04for the origins
23:05from his great-great-grandfather,
23:07Albert Perry,
23:09recorded in the registers
23:10census
23:11from 1870
23:12as a freed slave
23:13from South Carolina.
23:18It is indicated here
23:19that he is 43 years old.
23:21So he was born
23:22around 1827.
23:24Him,
23:24He is my great-grandfather.
23:25Clyde.
23:26He was only 3 years old.
23:30This major census
23:31is the first
23:32where the slaves
23:32are listed
23:33with their last name.
23:35Before that,
23:36they were essentially
23:37considered
23:38like the property
23:39of someone.
23:46Jacqueline Johnson
23:46was able to go back
23:47over 5 generations,
23:49no more than that.
23:51Before 1870,
23:53his family
23:53is not registered anywhere.
23:57Here is our family tree.
23:59That's me.
24:01my mother,
24:02my grandmother
24:03and my great-great-grandfather,
24:06Albert Perry.
24:08It's infuriating
24:10of not being able to
24:10go back further.
24:12People are not
24:14emerged from nothingness
24:14in 1870.
24:16They were alive before.
24:18SO,
24:19Where were they?
24:20I want to tell
24:21their story.
24:23I want to know
24:24who was Albert Perry.
24:25Who was Albert Perry?
24:28I recorded
24:29help
24:29of three scientists
24:31who use
24:32genetic ancestry
24:34in their research.
24:35In 2006,
24:37I was watching television
24:38the show
24:39African American Lives.
24:41People were talking about it
24:43of DNA.
24:54The participants were told
24:56"You are linked"
24:57to such a group in Liberia,
24:59to such and such a group in Nigeria.
25:01Got it
25:02that I had the solution,
25:03that I could analyze
25:05my own DNA
25:06to discover
25:07hence my family
25:08was originally
25:08in Africa.
25:14To study
25:15the lineage
25:16by Albert Perry,
25:17Jacqueline Johnson
25:18convinces
25:18one of his cousins
25:19to give
25:19a sample
25:20of its DNA.
25:22The analysis
25:23of the Y chromosome
25:24is carried out
25:25by a private company
25:26from Houston,
25:27led by
25:28Bennett Greenspan.
25:37When I arrived
25:39The morning,
25:40the technicians
25:41who had worked
25:42on the sample
25:42during the night
25:43were overexcited.
25:45They had never
25:46I've never seen anything like it.
25:50In general,
25:52we identify
25:53at most
25:53two or three
25:54new mutations.
25:55But this sample
25:57presented
25:57between 40 and 50.
26:00In other words,
26:01we came
26:02to discover
26:02a branch
26:04completely new
26:05of the family tree
26:06of humanity.
26:09The Y chromosome
26:11cousin
26:11by Jacqueline Johnson
26:12is so exceptional
26:14that we give him
26:14a name.
26:15A00.
26:19Geneticists
26:20are looking for an equivalent
26:21among the thousands
26:22of samples
26:23from their database.
26:24In vain.
26:29They then decide
26:30to extend
26:31their investigation
26:32to West Africa.
26:36The track
26:37they bring
26:37at 11,000 kilometers
26:38from Houston,
26:39in the village
26:40from Mbeta,
26:41in the West
26:42from Cameroon.
26:49In 2001,
26:50a program
26:51sampling
26:52of samples
26:52DNA
26:53had been launched
26:53in this region.
26:57The comparative study
26:58carried out in 2012
27:00reveals that 11 men
27:01of the village
27:01are carriers
27:02of chromosome A00.
27:08It is impossible
27:09to identify them,
27:10given
27:11that the tests
27:12were anonymous.
27:14But let it be known,
27:15they are the only ones
27:17in the world
27:17to have
27:17the same Y chromosome
27:18that the great-great-grandfather
27:20by Jacqueline Johnson,
27:21Albert Perry.
27:27The ancestor
27:28of the latter
27:28should therefore
27:29living in Mbeta
27:30when he was sent
27:31as a slave in the United States,
27:33carrying with him
27:34its genome.
27:44What the chromosome
27:46A00 has the most remarkable feature,
27:48That's his age.
27:51The analysis of these mutations
27:52has indeed allowed
27:54to determine
27:54that it was 338,000 years old.
28:00which means
28:01that he entered
28:02in the heritage
28:02hereditary
28:03of modern man
28:04before the period
28:05appearance
28:05supposed
28:06of the latter.
28:13The scientific theory
28:14shattered
28:15because this Y chromosome
28:18is the oldest
28:20never analyzed.
28:25And that's it.
28:27the whole interest
28:27of this discovery.
28:30We now know
28:32that humanity
28:32appeared
28:33much earlier
28:34that I didn't think
28:35scientists
28:36for years.
28:42Until recently,
28:43lineage
28:44of our species
28:45it seemed clearly established.
28:48Every man on Earth
28:49could claim
28:50from a common ancestor,
28:52the genetic tooth.
28:55And every woman
28:56descended
28:57of the genetic Eve.
29:00Homo 1
29:01195,000 years ago,
29:03which makes
29:04the fossil
29:04the oldest
29:05never discovered.
29:09At Gébel-Hiroud
29:10lived,
29:11300,000 years ago,
29:13a precursor
29:14of modern man.
29:18The appearance
29:19of chromosome A00
29:21however, it goes back
29:22even further
29:23since DNA
29:24that it contains
29:25is old
29:25338,000 years old.
29:27Enough to put back
29:28in question
29:29date of birth
29:30of our species
29:31Homo sapiens.
29:41When the results
29:42have arrived
29:43I was so excited.
29:45His name
29:45had entered
29:46in history.
29:47Do you realize?
29:48An unknown slave
29:49which was the property
29:50of another man
29:51which suddenly becomes
29:52famous throughout the world.
30:00It could also
30:02that modern man
30:03finally appeared
30:04in West Africa.
30:05But to prove it,
30:07geneticists
30:08will have to analyze
30:09more samples
30:10of DNA.
30:15Mathieu Forca
30:16is the researcher
30:17Cameroonian
30:18who proceeded
30:18at the first sample
30:19in the village
30:20of M-beta.
30:25I'm coming back here
30:26because it is
30:27on this population
30:28M-bo that I collected
30:29the samples
30:30DNA
30:3012 years ago.
30:32The analysis had revealed
30:33that we have
30:34carrier of the chromosome
30:36A00,
30:37which means
30:38their ancestors
30:39include
30:40the first representatives
30:41of humanity.
30:47Today,
30:49we will continue
30:50the levy
30:50DNA
30:51started in 2001.
30:53I'm going to rub you
30:54the inside of the mouth
30:55with a cotton swab
30:56sterile.
30:59The analyses
31:00are still ongoing
31:01and it is possible
31:02that they reveal
31:03that our species
31:03appeared
31:04in West Africa
31:05much earlier
31:05that anyone
31:06she hadn't imagined it.
31:14But there is
31:15maybe
31:16another explanation
31:17based on seniority
31:18of the A00.
31:19It's not us
31:20which we developed
31:21this chromosome.
31:22It was to us
31:23transmitted
31:24by a species
31:24human
31:25much older.
31:37According to the theory
31:38dominant,
31:39since its appearance
31:41nearly 200,000 years ago,
31:43modern man
31:43had almost
31:44no contact
31:45with other species
31:46human.
31:51and if this theory
31:53He was wrong.
31:57In Africa,
31:58for dozens
31:59thousands of years,
32:01Homo sapiens
32:02and archaic men
32:03have coexisted.
32:07and they were
32:09genetically
32:09quite close
32:10to transmit
32:11their DNA.
32:18It is possible
32:21populations
32:23archaic
32:24originating from Africa
32:25of the West
32:25have met
32:27by chance
32:27populations
32:28modern
32:30and it is transmitted to them
32:31this Y chromosome
32:32through interbreeding.
32:38The idea is
32:40than Homo sapiens
32:41continued
32:41to mate
32:42with archaic species
32:43inheriting thus
32:45of a part
32:45of their DNA.
32:55That would explain it
32:56why a handful
32:57of men in Cameroon
32:58are carriers
32:58of a Y chromosome
32:59338,000 years old.
33:10For about a hundred
33:11years,
33:12That fixed it.
33:13everyone
33:13spend
33:14that man
33:14had appeared
33:15in a Garden of Eden.
33:18Gold,
33:19DNA analysis
33:20we learn
33:20that modern man
33:21and different species
33:22archaic
33:23mated
33:24and who knows
33:25when it started.
33:27All of that
33:27brings us closer
33:28considerably
33:28other living beings.
33:38A discovery
33:39similar
33:39was done
33:40in southern Cameroon.
33:43in these forests
33:44tropical
33:45wet
33:45The Pygmies live there.
33:53These men count
33:54among the last
33:55hunter-gatherers
33:56of the planet.
33:57Their way of life
33:59remained almost
34:00unchanged
34:00for about a hundred
34:01thousands of years.
34:02They continue in this way
34:04to feed
34:04from what they find
34:05in nature.
34:24Genetically,
34:25the pygmies
34:26are the closest
34:26parents of the first
34:27modern men
34:28from Africa.
34:31and the results
34:32of the analysis
34:32of their DNA
34:33are very revealing.
34:37Geneticists
34:38are not interested
34:38only to their
34:39Y chromosomes
34:40and to their mitochondria.
34:41They are studying
34:42the entirety
34:43of the genome.
34:50And some
34:51regions
34:51chromosomal
34:52that they discover
34:53are so
34:53ancient and strange
34:54that they appear
34:56more archaic
34:56than modern.
35:00They too
35:01seem to be
35:01the fruit
35:02of a mixed heritage.
35:04But how
35:05Is that possible?
35:08According
35:09the tree of evolution,
35:11archaic men
35:12belong
35:13to species
35:13different
35:14of ours.
35:16Gold,
35:16by definition
35:17there cannot be
35:18crossing
35:19between topics
35:19of different species.
35:22The fact
35:23is that we were
35:24quite close
35:24genetically
35:25in order to be able
35:26cross the barrier
35:27of the species
35:27and continue
35:28to mate.
35:38Nobody knows
35:39how long
35:39archaic humans
35:40lived in Africa.
35:43The results
35:44analyses
35:45DNA
35:45suggest
35:46However
35:47that the exchanges
35:47between them
35:48and us
35:48were numerous
35:49and that of these crosses
35:50were born
35:51children
35:51viable,
35:52hybrid humans
35:53both archaic
35:54and modern.
36:10But what then?
36:11resembled
36:12These hybrids?
36:15That's what he's trying to do
36:16to discover
36:17the anthropologist
36:17Rebecca Ackerman
36:18studying
36:19mice.
36:26My approach
36:27may seem
36:28a little weird
36:28but it is impossible
36:29to hybridize people,
36:30primates
36:31in order to answer
36:32to these kinds of questions.
36:37These hybrid mice
36:38are very different
36:39from their parents.
36:40They have a body
36:41larger
36:42their fur
36:43does not have the same color
36:44and they didn't
36:44Not the same muzzle either.
36:47And above all,
36:48they are genetically
36:49highly variable.
36:53The variation being
36:54the engine of evolution,
36:56This explains the hybridization
36:57or an evolutionary force
36:59equally powerful.
37:02The project's objective
37:04is to study
37:05each aspect
37:05hybridization
37:07by dissecting the muscles
37:08and soft tissues
37:09mice.
37:14and also by examining
37:16the framework
37:16using a miniature scanner.
37:28The most interesting thing,
37:30it's about seeing
37:31what do they look like
37:31their skeletons
37:32because that's what will allow us
37:34to make the connection
37:35with human fossils.
37:36I remind you that the fossils
37:38are fossilized skeletons.
37:45We observe,
37:46among other things,
37:46than hybrid mice
37:48have snouts
37:48much bigger
37:49than those of their parents.
37:51In other words,
37:52hybridization
37:53is a source of genetic variations
37:55and trains
37:55a modification of the muzzle.
38:00When studying
38:01human fossils,
38:02we also observe
38:03that the face
38:04is one of the elements
38:05which change
38:05over time.
38:10It is therefore possible
38:11that hybridization
38:12either originally
38:13of this variation.
38:18There are about a hundred
38:19thousands of years,
38:20while their number
38:21increased,
38:22modern men
38:23They left from Africa.
38:28But they were not
38:29the first
38:30to undertake
38:30this migration.
38:34That was already
38:35at least
38:35one million and one
38:36half a year
38:36than archaic groups
38:37they too were leaving
38:38the continent.
38:41And some
38:41had passed
38:42so much time
38:43in Europe and Asia
38:44that they had evolved
38:45until forming
38:46different species.
38:51The most well-known
38:52of these humans
38:53is the man
38:53of Neanderthal.
38:55At the time of its discovery
38:56in the 19th century,
38:57we thought
38:58than an abyss
38:59separating him
38:59of modern man.
39:07He was considered
39:08like a bestial being
39:09and simian,
39:10inferior in every respect.
39:15From,
39:16He has been rehabilitated.
39:20Studies suggest
39:22Indeed
39:22that he resembled us
39:23more than we had imagined
39:27and that in fact,
39:29He is our cousin.
39:35If that is the case,
39:37has there been interbreeding?
39:38between our two species?
39:44In 2010,
39:46geneticists
39:47from the Max Planck Institute
39:48have succeeded
39:49to decipher
39:49the genetic code
39:50of a man
39:50of Neanderthal.
39:56They worked
39:57on a fragment
39:58of tibia
39:59which still contained
40:00traces of DNA
40:01despite a stay
40:0238,000 years old
40:02in a cave.
40:08Sequencing
40:09of a genome
40:10also old
40:11is a colossal task.
40:21Over time,
40:22DNA breaks down
40:24Indeed
40:24billions
40:25fragments
40:25which mix
40:26between them
40:26and are contaminated
40:27through DNA
40:28bacteria
40:29and insects.
40:35The difficulty
40:36for geneticists
40:37therefore consists
40:38to identify
40:38the fragments
40:39DNA
40:40Neanderthal,
40:41to isolate them
40:42and to assemble them
40:44in the correct order.
40:51It was necessary
40:52two and a half years
40:53to the devices
40:53sequencing
40:54to perform
40:55the first reconstruction
40:56genome
40:56of a human species
40:57turned off.
41:03Our main
41:04question
41:05was to know
41:05if men
41:06modern,
41:06when they had
41:07left Africa
41:08and met
41:08Neanderthals,
41:10had mixed
41:10with them.
41:14researchers
41:15compared
41:16the genome
41:16of man
41:16of Neanderthal
41:17with that
41:18of present-day Africans
41:19and they found
41:20no proof
41:21of miscegenation.
41:24Nothing out of the ordinary
41:26since the Neanderthals
41:27lived in Europe
41:28and not in Africa.
41:32then they performed
41:33the same comparison
41:34with Europeans
41:35of today
41:35and there,
41:36the results
41:37were very different.
41:44To my great surprise,
41:46we discovered
41:47that it existed
41:48a similarity
41:48a little more important
41:49between genomes
41:50Europeans
41:51and Neanderthals
41:52that between genomes
41:53Africans
41:53and Neanderthals.
41:57Even more surprising,
41:59we found
42:00the same degree
42:01similarity
42:01in the comparison
42:03with the Asians.
42:08In all genomes
42:09studied,
42:10the contribution
42:11Neanderthal
42:12appeared
42:12to be the same.
42:15Or Africa,
42:16the entirety
42:17of the world's population
42:19seems to have inherited
42:20between 1 and 3%
42:21DNA
42:22of Neanderthal.
42:28When we started
42:29our work,
42:30I was completely impartial.
42:32I thought
42:33that there had not been
42:33mixed heritage.
42:35But the results
42:36are here
42:36to prove to us
42:37that we were mistaken.
42:40It is obvious
42:41than the Neanderthals
42:42continue to live
42:43within us
42:44in many
42:45parts of the globe.
42:51There cannot be
42:52to that
42:53there is only one explanation.
42:54the two species
42:56they crossed paths
42:57somewhere
42:57outside
42:58from Africa,
42:59but really not far
43:00and before
43:01that modern man
43:02does not swarm everywhere
43:03on the planet.
43:05That somewhere,
43:07This is the current Middle East.
43:14Israel is a crossroads
43:15natural link between Africa,
43:17Arabia
43:18and Asia.
43:19A meeting place,
43:21a crucible.
43:27And he already was.
43:28to prehistory.
43:43The archaeologists
43:44who dig the earth
43:45of Galileo
43:45since the 1920s
43:47they made a discovery
43:48unique in the world.
43:55Leftovers
43:56of Neanderthals
43:58and modern men
43:58were exhumed
43:59in two neighboring caves.
44:04The two species
44:06therefore
44:06had to cohabit
44:07on these hills.
44:11The last cave
44:13to have been explored
44:14is that of Manot,
44:15discovered by chance
44:17in 2008
44:17during the work
44:18extension
44:19from the sewer of a village.
44:29The bulldozer was digging
44:31on this side.
44:32We can still see
44:32the notches
44:33in the rock.
44:36then he arrived here
44:37exactly in the spot
44:38where I am.
44:42Try to imagine
44:43the scene.
44:44The bulldozer
44:45is in the process
44:46to smash
44:47these enormous rocks
44:49boom boom boom
44:51and suddenly
44:51There's a hole.
45:03The anthropologist
45:04Israel Erschkowitz
45:05was one of the first
45:07to penetrate
45:07in the cave.
45:11It's beautiful !
45:13This former colonel
45:14of parachutist
45:14was able to descend
45:15as a reminder
45:16through the roof
45:16stoned
45:17during the works.
45:21When we entered
45:23in the cave
45:23It was dark
45:24total.
45:25We couldn't see it
45:26at one meter.
45:28We didn't realize
45:29right away
45:30how much
45:30she was immense
45:31and beautiful.
45:34Then we robbed
45:35our electric lamps
45:36and we discovered
45:38one of the places
45:39the most beautiful
45:39that I've never seen
45:40of my life.
45:42It's really
45:43an extraordinary cave.
45:52From,
45:53this cave
45:53has become
45:54an excavation site
45:55of major importance.
46:00The archaeologists
46:01they found
46:02quantity of tools,
46:03of bones
46:04and jewelry.
46:11Prehistoric men
46:12had obviously
46:13elected domicile
46:14in this place
46:15cool and humid.
46:23It's a departure from the rest
46:25in one of the rooms
46:26side walls of the cave
46:28that was exhumed
46:29the fossil
46:30the most spectacular.
46:35Imagine that you are moving forward
46:36in the darkness,
46:38equipped with a very small
46:39electric lamp,
46:41The place looks empty.
46:43Then suddenly,
46:44you turn your head
46:45to the right
46:46and on this ledge,
46:48over there,
46:48You see a skull,
46:50Nothing else.
46:53It's lying there.
46:54it is covered
46:55a thin layer of mud
46:57And there is nothing else.
46:59No tools,
47:00no animal bones,
47:02Nothing.
47:03Just a skull
47:04which is placed there
47:05for 55,000 years
47:06and who is waiting
47:07of being discovered.
47:15It's a skullcap,
47:18but of strange appearance,
47:20both modern
47:21and archaic.
47:30Roughly speaking,
47:31the shape of this skull
47:32is modern,
47:33but some of its features
47:34are still archaic.
47:36For example,
47:37the entire posterior part
47:38of the skull,
47:40It is convex,
47:42protruding.
47:44It's as if we had
47:45a bump here,
47:46at the back of the head.
47:51When you turn the cap over,
47:54we find the traces
47:55corresponding to the sinus of the brain.
48:00However, these brands
48:01that we see here
48:01these are not modern traits.
48:04This blend of characteristics
48:06on a single specimen
48:07can only be explained
48:09if we start from the hypothesis
48:10that the latter originated
48:11of a mixed heritage
48:12between modern men
48:14and Neanderthals.
48:2155,000 years ago,
48:23Homo sapiens migrated
48:24towards the eastern shore
48:25of the Mediterranean.
48:30At the same time,
48:31a period of cold
48:32in Europe
48:32pushed the Neanderthals
48:34ever further south.
48:36The two species
48:37were intended
48:38to meet.
48:46And that moment
48:47was a key event
48:48in history
48:49of our species.
48:57For the first time,
48:58we found each other
48:59face to face
49:00with our cousins,
49:01Neanderthal men.
49:13Up until now,
49:14the scientific community
49:15thought we had
49:16simply eliminated.
49:20Eventually,
49:21it seems that curiosity
49:23was strong enough
49:24to encourage us
49:25to become neighbors.
49:31This is the only place
49:33known worldwide
49:33where modern men
49:35and Neanderthals
49:36lived nearby
49:38from each other
49:39for at least
49:4010,000 years.
49:46Which, at one time,
49:48amounted to scientific heresy
49:49has become a scientific fact.
49:51There has been hybridization
49:53between Homo sapiens
49:54and Homo neanderthalensis.
50:06What the DNA revealed,
50:09a skullcap
50:10discovery in Galilee
50:11confirmed it.
50:21This skull,
50:22this fossil,
50:23that's the only proof
50:24anthropological
50:25available
50:26of a mixed heritage
50:27between the Neanderthals
50:28and modern men.
50:34But it is irrefutable.
50:42These scientific advances
50:43obliges us
50:44to be rewritten
50:44the history of humanity.
50:47The youth
50:48of our species
50:49seems to be indeed
50:50much more complicated
50:51that we thought so
50:56and also more fascinating.
51:02Throughout Africa,
51:03we were in contact
51:04with other humans
51:05and other species.
51:11We were not separated from them
51:13And today,
51:15They are part of us.
51:21when you bend down
51:22on the origin
51:23of our species
51:24we are in the presence
51:25of several human groups
51:26and we consider
51:27these groups
51:28as sufficiently different
51:29for having given them
51:30different names.
51:32Modern Men
51:33and archaic men.
51:34For us,
51:35this diversity
51:36is essential
51:37because visible
51:38and identifiable.
51:39But we don't know
51:40if, on their side,
51:41they considered
51:42as important
51:42the differences
51:43that they were observing
51:44around them.
51:47We know, however
51:48that there has been interbreeding
51:49between these groups.
51:51And the most amazing thing,
51:53that's the analysis
51:54of our genes
51:54provides proof of this.
52:00It's as if
52:01these archaic men
52:02were still alive
52:03in DNA
52:04of each and every one of us.
52:08We are all
52:09shaped by our past,
52:11through encounters
52:12which took place
52:13there are dozens
52:13thousands of years.
52:15Our species
52:16is a mosaic
52:17of different varieties
52:18of human beings.
52:24We are 7 billion
52:26of inhabitants on the planet.
52:28And we are all
52:29hybrids.
52:51Subtitling by Radio-Canada
52:53Subtitling by Radio-Canada
52:55Subtitling by Radio-Canada
53:01Subtitling by Radio-Canada
53:09Subtitling by Radio-Canada
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