BBC The Link Uncovering Our Earliest Ancestor (BBC The Link Uncovering Our Earliest Ancestor)

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For two years,
a team of top scientists have been secretly studying a unique fossil.
This fossil will probably be the one
that will be pictured in all text books for the next 100 years.
They believe it could be one of our earliest primate ancestors.
Well, it's really a kind of Rosetta Stone because it ties together
parts we haven't been able to associate before.
Have they found our oldest, complete, primate ancestor?
The fossil has more information in it then in any fossil I've ever seen.
Their research has stunned the world.
In the moment when the results of our investigations will be
published, this will be just like an asteroid hitting the earth.
47 million years ago the dinosaurs were already long extinct.
It's the time when the blueprints for modern mammals were being established.
Dense, tropical rainforests cover the earth.
They're home to small primates.
Among them is an ancestor to us all.
For almost 200 years, scientists have searched
for links to our prehistoric past.
The search has concentrated in East Africa,
known as the cradle of mankind.
Here in the 1970s, they found the link between apes and man.
It offered conclusive proof that we started walking upright 3.2 million years ago.
A human ancestor, a female, Lucy.
Then in 1984, the remains of a boy were found.
Material evidence that 1.5 million years ago, humans had already
lost their hair and taken their first steps onto the open savannah.
Scientists have long hoped that the earth might eventually yield
an even more ancient fossil that links apes, man
and all the other primates to the earliest mammals on earth.
This could be it.
A fossil so ancient it could shine a light deeper into our history than ever before.
And so detailed it could help science reveal the origins of every person on the planet.
This fossil is so complete.
Everything's there. It's unheard of in the primate fossil record at all.
You have to get to human burial to see something that's this complete.
This is really, really the most complete fossil primate ever.
World-renowned fossil expert Dr Jorn Hurum of Oslo University
has spent his life scouring the earth for important fossils.
But the most incredible specimen of them all,
the one that would change his life, took him totally by surprise.
It was in December 2006 at the annual Hamburg Fossil Fair.
Here the tables were laden with beautiful examples
of fossils and minerals to catch the public eye.
But Jorn didn't expect to find something for his museum on a stall.
The best specimens are never shown on a show.
They are always what we call "under the table".
So you need to know the dealers
to be shown the really, really, really good things.
The dealer, Thomas Perner, promised an extraordinary find.
When the dealer told me in the middle of the day
at a mineral show in Hamburg that I should join him for a drink
because he wanted to show me something,
I knew that it was something special.
Then he showed me some photographs and I was completely stunned.
And I didn't sleep for two nights after that,
because I knew that what I'd seen, it was probably
the most beautiful fossil I was ever going to see in my whole life.
Jorn made a home video of the very first moment
he came face to face with the fossil.
THEY LAUGH
Oh!
This is the best fossil and rarest fossil worldwide.
Wow!
Oh!
It's beautiful. It's beautiful.
Complete foot and two complete hands.
Yeah.
OK. Wow!
Yes!
Jorn believed he had stumbled across a 47-million-year-old treasure -
the perfectly preserved skeleton of a small creature,
more complete than he could ever hope for.
But his joy may be short-lived.
International fossil dealing is a cut-throat business.
Jorn must act swiftly if he wants to save it for science.
The thing about important fossils, there's a big black market and
there's a lot of private collectors, like with art and other things.
So a lot of important specimens are still locked in the basement of some rich guy or something like that.
So it needs to be in a public museum to be studied.
The asking price is over 1 million.
Jorn's got to be certain it's a genuine fossil and not a forgery.
He has it scientifically examined.
You can fake an outer surface of bone that looks really real,
but you cannot fake the inner structure of a bone.
It's impossible.
So getting an X-ray, you can see the inside of the bone.
You can see actually the bone marrow inside.
We know that it's 100% a real fossil.
There is no doubt at all.
The X-rays prove this fossil is genuine.
The necessary funds were secured and Jorn shipped it home.
In Norway's capital city, Oslo, in his museum lab,
Jorn finally gets to properly investigate his new treasure.
This is so complete that you cannot, even in your dreams,
wish for something being 47 million years old and this complete.
Usually, we only find teeth, broken parts of jaws
and small bones from the middle foot, maybe some toes and so on.
Just single, small bones from these animals this long ago.
Astonishingly, this fossil is not just bone.
Its level of preservation is extraordinary.
Here's an imprint of the bacteria that grew on the fur.
So actually we can see how much fur was there.
You cannot see the muscles or anything like that,
but you can see an outline of the body
that's bigger than just a skeleton.
You can actually see where the fur covered the animal
and how thick the fur was.
This unique fossil is so detailed
that it immediately reveals important information to Jorn.
The first thing I recognised was the big toe standing up like this,
90 degrees to the rest of the foot.
And if you look very careful, to both the fingers and the toes,
you can see that there were nails and not claws.
This is a primate, just from seeing that image of that foot.
It was really a wake-up call for me.
Apes, monkeys and us all belong to one particular group of mammals,
the primates.
And the common feature we all share
is four fingers and an opposable thumb -
the characteristic we share with this 47-million-year-old fossil.
Could we be related?
Looking at the hand, you can see that it's got five fingers, of course,
and nails on all the fingers. But also the thumb is opposable like us,
so it can grasp things, it can hold things the same way we do today.
It's already there 47 million years ago.
It's a proper hand to hold around things.
To properly analyse the fossil, Jorn must share his secret.
He handpicks a small team of experts,
each a world leader in their discipline.
I knew immediately that this fossil was too important.
So I started to invite people in to make a dream team
around this fossil, to make the first description really proper.
If I would do it alone, I'm not an expert in primates,
but there are some good people around the world
and I invited the best ones to join me and they all said yes.
Dr Holly Smith is a dental anthropologist.
By studying the fossil's teeth, she will be able to determine
what the creature ate, its age and how it compares to other primates.
The fossil could be the ancestor
of prosimians and apes and monkeys and the lineage leading up to man.
Joining the team is Dr Jens Franzen, a renowned fossil expert
who's been waiting for an opportunity such as this.
This is by far the most complete
fossil primate ever found on the world.
And we have not only the complete skeleton,
but we have also the complete soft body outline
and we have the gut content. So what do you want more, ja?
Hi! It's nice to see you. How was the flight?
Professor Philip Gingerich is the next on board.
He's spent his life searching for links between early and modern mammals.
I suppose one of my initial thoughts was,
"This is a big job. This will be a lot of work."
Partly because there isn't anything else like it
and so it really deserves to be compared carefully
with all the various fragmentary fossils we have
and also with the skeletons of the living ones.
And you put all that together, that's a big work.
They plan a long and thorough study.
They must be certain of their conclusions
before they reveal the fossil to the world.
Until then, they will work in secret on their extraordinary treasure.
As soon as they start their analysis,
the fossil begins to come to life before their eyes.
The pelvic region, of course,
it's possible actually to tell the sex from this area.
In this region, you will expect to see a baculum or not.
All primates at that time possessed a penis bone, known as a baculum.
We now know from looking at the specimen
that there's no baculum present.
So this is a girl,
this is a small female that lived 47 million years ago.
The investigation is gathering pace.
The next question is where does she come from?
And it's the way her delicate body has been preserved,
and not her skeleton, that provides the answers.
There's only one locality in the world where this transfer technique,
that the fossils are put in this kind of polyester,
that all the fossils are prepared like this. This is the only place.
All the major primate fossil finds until now have been made in Africa.
But this one has been prepared using resin,
a technique used, not in Africa, but in Germany.
The fossil was found here, in a place known as the Messel Pit.
There is nowhere in the world like it.
It's an ancient crater filled with an unrivalled collection
of fossils, all dating from the Eocene Period, 47 million years ago.
It's like a peek-hole into a whole community,
a whole ecosystem in the Eocene.
That suddenly you see that everything you find usually
as small pieces of things, you have complete
in this one locality, one place in the world
and that's something that palaeontologists really, really treasure.
So this is like a holy grail for palaeontology.
Dinosaurs were long extinct.
The shales of Messel had already yielded fossil birds,
reptiles and amphibians,
complete with the impression of their feathers, scales and skin.
The biggest ants ever known
and beetles, still with their colour after millions of years.
Preserved in incredible detail are bats,
snakes and even a miniature horse the size of a small dog.
The first glimpses of kinds of creatures that are alive today.
The Eocene Period is really the critical stage for mammal evolution.
It's when all the old-timers, they are still around
and the newcomers are coming strongly into the field.
We have the first horses, the first carnivores,
the first bats, the first whales. All these new mammals are evolving
in the Eocene and, of course, the primates, they are thriving.
But which were our ancestors?
Until now, no complete primate has ever been found in the Messel Pit,
and even this specimen was almost lost forever.
Fossil hunters have dug in the Messel Pit for generations,
collecting and selling the specimens as works of art,
just such a fossil hunter must have dug this primate from the shale.
Who this was is still a mystery, but we do know they took her away,
perfectly preserved her in resin
and locked her away from view for 25 years.
It's like having your unknown Rembrandt,
your unknown Van Gogh, at home.
You can see it every day. The rest of the world don't know about it.
And it makes you kind of feel powerful I think to have something like that.
Fortunately, now she's with Jorn,
her secrets can be revealed to the world and the team in Oslo
are starting to examine and describe her skeleton bone by bone.
By why are fossils from the Messel Pit so well preserved?
It's thanks to the formation of the Messel Pit 50 million years ago.
Deep underground, molten rock, magma, forced its way upwards.
Just below the surface, it meant a layer of ground water.
Superheated steam generated incredible pressure.
The rock was ripped apart.
A series of massive explosions
created a crater a mile wide.
Inside its steep walls, an incredibly deep lake formed.
It was probably at least 100m deep and the waters were still.
When animals fell in,
they drifted down and were soon covered by mud at the bottom.
There was no oxygen and few bacteria to induce decay.
Undisturbed for millions of years,
the bodies, buried under tonnes of mud, were squashed flat.
It is the Messel Pit's extraordinary geological history
that allows Jorn to pinpoint exactly when this fossil lived.
The start of this whole lake, where the fossil was found,
that was a volcanic explosion, and parts of that volcanics
that came out in the explosion, they are like time capsules.
And it's possible to date the radioactive isotopes
in such volcanic rocks very, very precisely.
And this has been done for this volcanics and it's 47 million years.
Despite the millions of years that have passed since these animals were alive,
their bodies have been preserved in such detail
that they give us a full picture of their world.
The preservation at Messel really brings things to life and you can
really get a feel for this as an animal and not just as something...
A pile of bones, long dead.
Eocene Europe was very different than it is today.
Continents have drifted, sea levels changed.
Then the world's climate was more humid and tropical.
The primates' home around the lake was a lush, tropical rainforest,
a green canopy of trees stretched as far as the eye could see.
In the skies were birds and bats.
On the ground,
new kinds of furry, warm-blooded creatures were flourishing,
the early mammals.
This is where our fossil lived out her life as a prehistoric primate.
She lived in a dense jungle of tall trees and vines.
As the team continue to examine her skeleton,
they're able to deduce how she lived.
All through looking at the skeleton, we can be for sure
that it was living on trees because when you are looking at the thumb
and also at the big toe of the feet,
you can see that these were grasping hands and grasping feet.
So these were feet constructed for
an animal living on trees, evidently, ja. No doubt about that.
It's possible to say something about the size of the muscles
from the attachment points on the bones.
What's special about this small skeleton is really that both
the arms and legs are quite short and quite strong for such a small animal.
So probably she had quite a lot of muscles.
This new information adds to the picture the team are building
of a strong, muscular creature living high in the tree tops of the Eocene rainforest.
But what did she eat?
To understand precisely what she ate,
the team look at her teeth.
Dr Holly Smith is an internationally renowned dental anthropologist.
She wants to see inside the fossil's mouth,
but it's been firmly shut for 47 million years.
Only detailed X-rays have enabled her
to examine the shape and structure of the fossil's teeth.
So the Messel primate has a nice, kind of general primate dentition
that could do a little of everything.
She's got a little bit of an incising surface.
She's going to have plenty of piercing teeth.
She has molars that are general but have some kind of slicing edges.
And we would expect that a real primate, a real arboreal primate,
would be eating probably fruit and leaves
and maybe supplementing that with insects.
This extraordinary preservation is not restricted to her teeth.
As well as the fur, there are other delicate details
that provide information which never ceases to astonish them.
What's amazing about this specimen is also that
we can actually see its gut contents.
It's the last meal preserved in this small female.
Even with this nugget of petrified treasure,
decoding the fossil's secrets doesn't come easy.
But Jens manages to puzzle it out.
Before I had seen that several times and I thought all the time,
"Oh, that's a scale of a fish quite common in Messel."
And then I saw the cell structure
and I realised, "Oh, no! This must be the remnant of a plant."
And then looking at the morphometry and at the form of that particle,
it became immediately clear that this can only be a seed, ja.
So it seems that just before she died,
this tree-dwelling primate fed on fruits, seeds and leaves.
As the team examined the X-rays in more detail,
something just isn't adding up.
They've realised that her jaw held
an extraordinarily large number of teeth.
This is the radiograph from this side and you see
the drawing of the teeth matches pretty well.
The team have a real puzzle on their hands.
They're going to need more than a standard X-ray to solve it.
The Senckenberg Institute in Germany
specialises in high-end computer tomography, CT scanning.
Images of the rotating fossil are recorded and manipulated
by powerful computers, which, just like a CAT scan in a hospital,
create an image of the fossil's jaw in 3-D.
Then we've taken X-rays and so you can get
the shadows of what's behind what you can see.
And then in the last year, we've done computerised tomography,
where you literally... you project X-rays
in a way that literally slices the fossil into many, many, many slices
and made into a three-dimensional image,
so you can literally step through from the front to the back.
You can even manipulate the CT scan so that you see
what you're looking at, not from the front, but from the back.
It's as if there are no secrets.
The best person to help analyse such phenomenally detailed
three-dimensional images is the scanner supervisor
Dr Jorg Habersetzer.
Here is the region of the molars.
And if we zoom in, which is not possible on normal CTs,
we see all the details preserved in three dimensions.
So we can follow up all ridges
and the cusp of the teeth in a three-dimensional way.
This computer tomography has revealed something extraordinary.
You can also see, for example on this assemblage,
that the second molar here has not evolved complete roots,
whereas in the first molar we have here already very solid roots.
Here is the answer to why they found so many teeth in the fossil's mouth.
She has her baby teeth as well as her unerupted adult's teeth
still buried in her jaw.
This primate was a youngster.
So this Messel primate was caught at a really interesting
and very distinctive time in her life.
She's clearly no longer an infant,
but she's not grown up.
She's a juvenile. She might be, let's say, very roughly comparable
to something in a human like a child somewhere between six and 12.
It was a girl, a small girl, which had this tragic end
there in the crater lake of Messel 47 million years ago, ja.
She's in a developmental phase that looks very much like
a six-year-old human in comparison
and I'm so lucky that I have a daughter that's five-years-old
and she's starting to shed her teeth just now.
So we decided, after some discussion,
to name the fossil, to name this wonderful little primate, Ida,
because that's the name of my daughter.
LITTLE GIRL LAUGHS
So Jorn now has two Idas in his life.
One five-years-old and one 47 million.
At this point in the investigation, they've gathered so much information
that it's possible to fully reconstruct her ancient skeleton.
Her 47-million-year-old remains
can be brought to life in the 21st-century virtual world.
Laser scanners, combined with the computerised tomography,
produce a digital code of her body,
which, once processed, creates an accurate 3-D model.
We are able, using these tools, to see Ida as never before.
Ida is a warm-blooded creature covered in thick fur.
She was just under a metre long, including her tail,
which she used for balance as she scampered on all fours
through the rainforest canopy.
Her opposable thumbs and toes gripped the branches.
Ida was probably active at night.
Like us, her two large, forward-facing eyes
gave her excellent stereoscopic vision.
The team's extensive analysis, combined with X-rays and CT scans,
have brought them a long way in understanding Ida.
The investigation is however far from over.
There are still many questions to answer.
Most importantly,
how significant is she to our understanding of our evolution?
Does she belong on the evolutionary branch that leads to us?
The Eocene Period in which she lived
was a crucial time in the history of life.
Without the developments that happened, we would not exist now.
At some point during this new dawn,
the primates split into two major groups.
The prosimians, the non-human branch,
which still survive mainly as modern lemurs.
The other branch, the anthropoids,
developed into monkeys, apes
and, ultimately, us, humans.
Well, the advance of having a skeleton this complete
is hopefully it will let us make the connection to what came later.
In a sense, studying primate evolution is all about
looking at the diversity living today and tracing that back through time.
We're interested here to see how apes and monkeys trace back.
How lemurs trace back.
And which of these, or all of them, can we find in the Eocene.
But what is Ida?
Is she our ancestor or is she on the non-human line, a lemur?
Any partial primate remains discovered at Messel so far
have been described as lemurs.
The first guess, of course, because of the other specimens that's found
from the Messel locality is to say, "OK, this is a primitive lemur."
Most lemurs are the size of monkeys
and have similar habits and lifestyles.
But they are an evolutionary side branch.
They've hardly changed fundamentally in 47 million years.
If Ida is closely related to modern lemurs,
then she cannot be a human ancestor.
It's a critical stage of the investigation.
It's really important to compare this fossil to living lemurs
because living lemurs have many not so advanced traits.
And a lot of the traits that we see in lemurs today
is the same things that we should look for in the Eocene,
when all primates were really primitive.
Dental expert Dr Holly Smith is at Duke Lemur Centre in North Carolina.
This is the world's largest research centre for the non-human line
of primates and here they have a great variety of them,
including tarsiers, loris and lemurs.
Is there one that is particularly similar to Ida?
The Messel primate isn't exactly like anything living
and one of the questions is, is it general enough
to have been a possible ancestor for the higher primates,
the apes and monkeys and perhaps these animals, too?
Or was it already specially off on a line to lemurs?
But if you want to study one of these creatures, there's a problem.
Getting it to keep still.
Fortunately, this loris is being examined under sedation by the centre's vet.
And we're doing a physical exam, his annual physical exam, under sedation.
By having a really close look at this animal,
we can see characteristics that proves it is not our close relative.
Most of their toes have toenails like we would have,
but this second digit has a long grooming claw.
All lower primates have such a grooming claw on the hind foot.
They can use that for grooming their fur
and you can see a primate's got a really lush, thick coat of fur
and keeping that in condition is important.
The vet continues by checking this creature's teeth,
Holly's particular expertise.
He reveals another important characteristic
that places it on the non-human branch of evolution.
So he has the upper incisors here, the canines, and then on the bottom,
his incisors and canines form this tooth comb.
These animals have unusual front teeth in their lower jaw.
Where we and apes and monkeys have separate front teeth,
these creatures have a tooth comb.
Some of the lemur's specialisation is used for getting food,
but it's also used for grooming fur and grooming each other.
The big question for Jorn and the team is,
does Ida belong with them or with us?
Does she have the grooming claw and a tooth comb?
So looking at this toe here,
certainly, it's just as wide as the others.
There's not a pointy toe tip,
like you expect in lemurs when there's a toilet claw present.
There's nothing like this here.
This is also nail-bearing.
One of the other main lemur traits is, of course, a tooth comb.
And we would expect this, of course, in the front of the snout
and there's no tooth comb here at all.
There's nothing like that in this specimen.
Ida's skeleton is over 95% complete, so the team know
that these features haven't been lost in collection or preparation.
Put simply, she never possessed them.
Unlike the other fossils found in the ancient Messel Pit,
she is not a lemur.
She must be a member of another group.
Could she be in a group connected to us?
In the beginning, we all thought
we are just dealing with a certain kind of fossil lemur
and, step by step, our ideas changed
and more and more anthropoid traits
turned up and now we are really thinking of relationships
to anthropoids, to hominoids finally and at the end to man.
The team have shown that Ida is not on the lemur line of evolution.
But is she on the human line?
Jorn and the team want to look to the forests of East Africa
and our closest relative, the chimpanzee.
If we look at the anthropoid primates, we have to go to Africa
to look at chimpanzees to see something that's more advanced,
more specialised, in a way that's a little bit more like human traits.
It's wonderful. You can compare them
and you can compare their skeletal features with Ida.
Ida shares the classic primate characteristics with chimps.
They are quadrupeds,
walking on all fours, as she would have done in the ancient forest.
Strikingly, their hands and feet are almost identical -
five fingers and five toes.
And her opposable big toe, the trait that first identified her to Jorn
as a primate, is mirrored in the chimpanzees.
It enables both of them to grasp tree branches and climb.
Looking at modern-day chimpanzees
and looking at the foot of a chimpanzee
and looking at especially the ankle bones,
they are so much the same as in the fossil.
At this stage of the investigation,
Ida is showing some basic human-like characteristics in her skeleton,
but her body proportions and the length of her fingers
are nonetheless lemur-like.
The picture is still unclear.
It is, broadly speaking, a lemur monkey.
How lemur it is and how monkey it is, is what we're trying to figure out.
And so...
it looks to me like it ties
higher primates, apes and monkeys,
into something in the Eocene that's clearly more primitive.
The team are looking for any clear evidence in Ida's anatomy that links her to us.
This is not an easy task.
Establishing these links has always been a problem
since the theory of evolution was first proposed.
150 years ago, Charles Darwin explained the incredible diversity
of life on earth in a new way.
There are billions of species on the planet,
but each was not individually and uniquely created.
New species appeared as they adapted to a changing environment.
At the time, Darwin's proposal was controversial.
He argued that monkeys, apes and ourselves have a common ancestor.
That ancestor, we now know,
must have lived hundreds of millions of years ago.
Darwin's idea was revolutionary
and he was ridiculed by many in Victorian society.
"Where is the proof?" his critics demanded.
"Where is the half ape, half man fossil
"that links us to ape-like ancestors?
"And where is the even more ancient fossil
"that links apes and ourselves to the rest of the animal kingdom?"
Darwin predicted that such creatures must have existed,
but he never could produce the fossil evidence.
It was missing.
Don Johanson is famous as the man who found
what the world had been waiting for, one of those missing links.
In the Ethiopian desert in 1974, as a young man,
he uncovered the fossilised bones of an astonishing creature.
He nicknamed it Lucy.
Incredible. Just remarkable.
Well, what we're looking at here is about 40% of a single skeleton,
of course, the Lucy skeleton, which I found in 1974.
And what's astonishing about it is we have parts of the upper limbs,
the arms, we have parts of the lower limbs,
both the thigh and the shin bone.
Parts of the vertebral column, the backbone, and even the ribs.
And when we mount her like this, when we make a display like this,
one gets the impression of the body.
Lucy looked like an ape,
but she was beginning to show human characteristics in her skeleton.
She turned out to be an extraordinary link in our own evolution.
Finding Lucy, of course, it's a fantastic fossil
that shows the upright position, the standing position,
the walking of the first human-like ancestors.
So she's a hallmark because she walks like us.
One of the things that Lucy gives us
is a real picture of what her pelvis looked like.
The pelvis is obviously one of the most crucial
anatomical regions in the body for the way animals get around.
For example, if we look at an animal that walks on all fours,
a quadruped, and in this case it's a chimpanzee,
you can see that the hip bones - it's the one we feel just here -
as you can see, are facing forwards.
Whereas in humans, like ourselves, they have been rotated around
so that the muscles on the back are now on the side.
They're no longer facing backwards.
And they stabilise the hip.
So that when we walk, we walk as a striding gait.
If you watch a chimpanzee walk bipedally,
it walks like this, cos it's always collapsing.
So animals that walk on all fours, like chimpanzees and Ida,
have a very different hip bone to animals that walk on two, like us.
But it was the shape of Lucy's bones
that revealed an amazing fact about our own evolution.
If you look at Lucy's pelvis, right here -
we've reconstructed this side for the mirror image -
it's not identical to a modern human.
But clearly, it's shorter, broader
and these blades, the hip bones, have been rotated around.
So this is a clear adaptation to upright walking on the ground.
Lucy had ape characteristics.
She was hairy, like a chimpanzee.
But she also had human characteristics.
She walked on two legs, just as we do.
Lucy was the half ape/half man species that Darwin predicted.
But where was the link millions of years earlier
between us and the rest of the animal kingdom?
At this stage of the investigation, Ida's skeleton is showing
a mixture of characteristics from the non-human and human line.
This unusual combination is bringing Jorn and the team closer
to deciding whether she is related to us.
This jumble of different characters, it's very, very exciting,
because you see things that are more anthropoid like.
You see things that are certainly extremely primitive.
You see things that maybe should be more like a lemur.
And you see all these characters in the same skeleton
and you need to try to explain evolution in a new way,
the early evolution of primates, in a new way, because it's there.
You cannot take them away.
This is really one specimen that's frozen in time
and all these characters are there.
Jorn and the team are getting closer to proving
that Ida is the ancestor of all monkeys, apes and humans.
But they need to find final proof of that in her skeleton.
Lucy's pelvis gave Johanson the proof of an ape/man.
Finding an equivalent bone to link Ida to us is much more difficult.
3.2 million years of evolution separate us from Lucy.
But 47 million separate us from Ida.
That's an immense length of time.
Jorn and the team start scrutinising every inch of Ida's body,
when suddenly they are distracted by something that tells them,
not about OUR evolutionary story, but about HER personal story.
Dr Jens Franzen was analysing Ida's wrist when he noticed something
that suggests she may have suffered an injury in her young life.
Suddenly I saw the small fragments of bone and this
fine structure on the surface, which is typical for a bone.
And so it was like a lightning at that point. "Ah, yes!"
But really here, really it's possible to see it.
Because the bone is in small, small pieces fused together
at the end of the wrist. Yeah. It's not a nodule.
It's not something that was formed after the animal was dead. Right.
This is something that happened to her while she was still alive.
What Jens found in the wrist, it's quite amazing, because
it looks like the wrist here is broken and it's partly healed again.
And when it healed, it was a lot of new bone
forming on top of the joint for the hand. So her right hand
was not functioning very well after this accident.
Research on her bones has thrown up a tragic surprise.
The lump on her right wrist shows that she broke it very badly early in her life.
Maybe she was dropped by her mother.
The wrist continued to grow, but it was badly deformed.
Her hand didn't work well
and the team believe she might not have been able to climb properly.
She was probably forced to forage for food on the ground.
And tragically for the injured Ida,
the volcanic forces that formed the Messel lake were still active.
They played a crucial role in her demise.
The still waters of the lake were often covered
by a low-lying blanket of gas, a poisonous but undetectable
layer of carbon dioxide seeping from the ground.
She was thirsty and so she went to the lake shore and tried
to drink there, not realising that this was a bad day for her,
because at that day such a poisonous gas layer had developed
and so she must have lost immediately consciousness
and then she fell into the water and she drowned.
Sinking quickly through the waters, she slid into the mud,
deep below the surface, where she lay for 47 million years.
The bone in Ida's wrist has given the team an extraordinary personal story to Ida's death.
But they're still looking for a bone to link her with us.
They have exhaustively studied her skeleton
throughout a long investigation.
They're hoping she might be linked to our own ancestral line.
It's been a long journey describing this fossil.
From the start, where we all really believed strongly
that she's a fantastic fossil but she's related to lemurs,
until we now after unwinding one character after the other,
finding that this doesn't fit, this doesn't fit. This is something else.
And looking at it now,
it looks so much more exciting even than a complete lemur.
This is something much more important also for our own evolution.
Jorn and the team still need to find
that one conclusive piece of evidence that will allow them
to be sure that she is our relative. It's only after two years of work
that they make a startling new discovery.
This is even shorter.
There is a bone in Ida's foot
that links her with every person on the planet.
It could be the evidence that the first small adaptations
towards walking upright happened 47 million years ago.
The ankle born, the so-called talus in the Messel primate,
shows exactly the evidence which we see still in ourselves,
in human beings of today.
Except that, of course, our bones are much bigger now.
But they show the same kind of articulation, ja.
A tiny bone in her ankle, the talus,
is shaped like that of a modern human.
It is critical in connecting the leg to the foot
and is key for bearing weight.
This is crucial in making it possible to walk upright.
Its shape is restricted to monkeys, apes and humans.
The lemurs and the other prosimians
have a bone of a completely different shape.
The shape of this bone tells something about the movement of the foot.
And the movement of the foot of primates
is quite different in different groups and this particular shape
on the talus bone, it's very, very much like humans.
This shaped foot bone makes Ida one of us.
Our 47-million-year-old relative.
We are really dealing with
a very, very early root of anthropoids at Messel, ja.
Ida comes from a crucial point in our evolution,
when the early primates split into the human and non-human groups.
She is a fusion of both.
She is a transitional species, a link that is now no longer missing.
It tells a part of our evolution that's been hidden so far.
It's been hidden because all the other specimens are so incomplete.
They're so broken, there's nothing almost to study.
And now this wonderful fossil appears
and it makes the story so much easier to tell.
And so it's really a dream come true.
We could all be descended from Ida.
Jorn and his team believe they have discovered our earliest, complete primate ancestor.
And remarkably,
exactly 150 years after Darwin put forward the proposition
that human beings were part of the rest of animal life,
here at last we have a link which connects us
with, not only the apes and monkeys,
but also with the entire animal kingdom.
This fossil turns out to be really important for us, as humans.
This fossil is really a part of our history.
Truly, a fossil that's a world heritage.
This is the first link to human evolution,
long before we started to divide into different ethnic groups.
A find like this is something for all human kind.
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