>> I think basically it's a human characteristic
that we are curious.
And when you look anthropologically
around the world, you can pretty much name the culture.
And they'll have a creation story.
We know our own from the Judea Christian tradition.
Those of us from Northern Europe and that tradition.
There are others in South Asia.
There are others in Aboriginal, Australia.
There are others right here in California.
And there's only one way to figure out what really happened.
So if you treat it more like a forensic science and ask,
let's figure out what happened here.
Let's not wave our arms.
Let's not imagine.
Let's not speculate.
Let's not do science fiction.
Let's do science.
Well in 1990, we had worked on the east side of the river.
We had found the Lucy species, equivalent to the bottom
of the Hadar formation.
And we'd seen sediments a little deeper in time.
Unfortunately, they were all lake beds.
And you don't find early hominids or other primates
in the middle of a lake.
So we had to get to the edge.
And by doing that on the west side of the river, we were able
to push deeper into time.
And we found one band at about 5.2 million years.
Very rich invertebrate fossils.
But we were really frustrated.
Because we couldn't find any hominids at all.
We had horses, pigs, hippos, rhinos, elephant,
all kinds of fauna, gigantic tortoises,
but we couldn't get any hominids.
And we couldn't figure out why.
And right at the end of the field season we finally said,
you know, we're not just getting hominids.
Let's move up the stratigraphy a notch.
And we found a horizon at 4.4 million years ago
that just hit the right ecological circumstances
that had hominids living, dying and now their bones
after being suspended there for 4.4 million years eroding
out on to the surface.
So we were able to put a team on those rocks and begin to exploit
that 4.4 million year old horizon.
So we went.
We put teams in the field.
We found more bits and pieces.
We found a base of a hominid cranium.
We found associated dentitions.
We found a partial arm.
And we thought, this is great.
We went back in the 94 season to see if we could find the rest
of that individual whose arm we had found.
And it turned out that we couldn't.
But nearby we found a different individual's skeleton.
And when we first found it, it didn't look
like a skeleton at all.
A graduate student at the time, [foreign name],
young Ethiopian scholar, highly trained osteologist,
found two little pieces from the palm
of the hand, just this bone here.
And these little pieces he picked up and said,
this looks like a hominid.
So we did what we always do.
We scooped up all the loose already eroded sediment.
We run it through a very fine grid, a sieve,
and then we picked other pieces out.
And as we picked other pieces out, we would find micro mammals
and bovids and monkeys.
But there were hominid hand and foot bones.
And as we scraped and brushed that surface, we found some
of these bones in place.
And so for the rest of that 1994 field season,
we focused on that little hill.
And we were rewarded with a very dense scatter of pieces
from a single female individual's skeleton.
Affording us a really unprecedented look
into the hands and the feet and the pelvis, the arms, the jaws,
the teeth, the skull of that individual
who had died 4.4 million years ago.
Arte is a young adult female.
We know that from the bone fusion.
We know it from the eruption of her dentition.
She died fairly young.
We don't know why.
But we now have hand proportion.
Foot proportion.
Limb proportion.
And we learned a lot of things about the biology
of this creature from this assemblage of more
than 120 pieces of bone all from that one excavation.
And so we're able now to realize
that this is a creature unlike anything that we've seen before.
In living primates or even the fossil record.
This is a creature for example, that retained the ability
to grasp with the big toe.
That is something that humans don't do
and Australopithecus didn't do.
But Arte did.
Then we could ask questions about the rest of the body.
What were her limb proportions like?
How did her wrist function?
And we learned from that and from the bones of the hand
that it didn't function like a chimpanzee's functions.
It's not a knuckle walker's hand.
It's the hand of something else.
It's not human.
But neither is it chimpanzee.
And so by going through each part of her anatomy,
we're able to understand better the adaptations
that characterized the earliest known members of a lineage
that ultimately would become human.
She's by no means a human.
Now what about the world she lived in?
Well we can't learn that directly from her skeleton.
But when we look at the pelvis we see adaptations to climbing
that are absent in the Lucy species.
So this is a very, very early biped still well adapted
to our boreal existence beginning to work
on terrestrial resources.
But not in the kinds of ecological settings seen
in the Lucy species or later hominid species.
What we found from those tens of thousands of associated fossils,
plants, animals, birds, all of the rest,
was that she occupied a woodland setting.
Not an open grassland Savannah.
And this also constitutes a kind of a breakthrough
in the understanding of the earliest hominids.
And it comes back and it answers that question, that mystery,
of why we couldn't find any hominids
down low in the stratigraphy.
It turns out that hominids are very,
very habitat restricted early on in time.
It's only later as Lucy and then her decedents arise
that the ecological niche of hominids broaden to the extent
that we can expect to find their remains
in lots of different places.
If you go early in time, hominids are rare
because they're ecologically restricted.