National Geographic: The New Chimpanzees Page #4

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in front of me with a big tree,

big branch sticking out

and I heard some banging so I

approached without making a slightest noise

and I hear the chimps coming,

they passed me,

I could fee their warmth,

I could smell them,

they all started climbing up these

trees with big tools in their hands

and banging on something

which I finally realized

they were cracking nuts.

The sight is unforgettable something

of prehistoric times,

the image of these great animals

using these big tools.

To crack nuts,

the chimps seem to have grasped

the concepts of hammer and anvil.

The anvil is a tree root; the hammer,

a wooden club,

or sometimes even a stone.

Although it may seem effortless,

it takes a decade of practice before

the chimps develop real expertise.

When you look at these images

of chimps cracking nuts,

it looks terribly easy and people

don't realize how difficult it is.

I made an experiment:

I asked a primatologist

who came to visit me here,

I gave him some nuts and a nice place

in the forest and I told him,

yeah, crack some nuts now.

You will see how easy it really is.

It took him 25 minutes

to open the first nut.

He took him 40 minutes

to eat three nuts.

And you can imagine,

if you really have to fight 40 minutes

for three nuts it's not worth it.

I remember the very first time

I saw a female mother

who was looking at her five year old

trying to crack a nut

and she was fighting with a very,

very strange formed club and she was

changing her position all the time

and changing the grip of the hammer

and didn't succeed.

And she was starting to whimper,

not knowing what to do.

And then the mother came,

the infant immediately stepped

a bit backward

and the mother took the hammer

and in a very slow motion move,

she turned the hammer

and just the move,

this turning the hammer,

took her a whole minute,

so it was even slower than I did,

and as to emphasize,

that's the way you should hold

the hammer

and she cracked for some nuts for her

and then left and

the infant tried again

with exactly the same grip

as the mother.

She still had some trouble to crack

the nuts so she changed position,

changed the place of the hammer,

but kept all the time exactly the

same grip as the mother showed her.

So, that's really correcting an error

in an infant

which is really the highest

form we would consider

of active teaching

and that just was kind of a surprise

for the first observation in animal,

for the animal doing that.

A young chimp's tutor is its mother,

who teaches it most of the skills it

needs to survive.

The Boesch's research has shown

that female chimps are the most expert

and dedicated tool users,

which may shed some light

onto the origins

of tool use among our own ancestors.

Already here we have a slight sexual

difference in favor of females

in that they crack more then males.

Another technique to crack nuts up

in the trees is much more often done

by females and they have to anticipate

bring the hammer up on a branch

in the tree and then they have to

handle it up there,

hold the nuts in a fruit in the hand,

hold the hammer,

hold the baby and still crack somehow

and eat these nuts.

And then we have a nut species Panda

nuts, very hard,

you need stone tools to open it.

Stones are a rarity in the forest,

again, this technique is

more often done by females.

It could make you think

that maybe tool use

in our ancestors was also

a female activity

and the first tool users and tool

invertors may well have been females.

Females also transport learned skills

between chimp communities

when they move from group to group

at adolescence.

But, sadly, as chimp populations

become increasingly isolated this kind

of cultural exchange

will come to an end.

Only recently have researchers

all across Africa

realized that some of the differences

between their study groups were

cultural due to the invention

and passing along of learned traditions.

In the Kibale Forest of Uganda,

Richard Wrangham has found that

it is culture

which enables some chimps

to eat foods others must forgo.

So, here we got a safari ant nest

and in five years

we have clear evidence

that the chimps here

do not every eat these,

but in Tai and in Gombe

this is what they do.

A wand onto the nest

and then sweep the ants up,

biting, no neat test,

you've got to be pretty quick and

you've got to know what you're doing.

Now, having just tasted them,

I can understand

why chimps like to eat them,

but, on the whole,

I'd prefer not to, myself.

Every chimp group has

its own unique tool kit.

Only at some locations

have they learned to use wands

to capture ants or termites.

At Tai, they use bone picks

to dig out the marrow,

just as our earliest ancestors did.

They will also use a wodge

of fruit as a sponge,

to help squeeze out every trace

of sweetness from the pulp.

While at Gombe, as well as at Tai,

chewed leaves make a sponge to quench

the thirst at shallow puddles.

We have only begun to realize the depth

of the traditional knowledge generated

by the various "nations" of chimps.

One puzzling cultural practice is the

eating of hairy and unpalatable leaves

They ball them up in their mouths,

forcing them down whole.

Well, here I've got one of the leaves

that is swallowed hole by chimpanzees.

This particular one is the one

that the chimpanzees tend to swallow,

at dawn,

why they do it at dawn is not certain.

Well, one possibility is

they're helping to remove worms.

This is so new that we don't even know

the name of this.

We think it's part of a tape worm

and it looks as though,

when the chimpanzees

have this tapeworm,

they swallow the leaves

in order to expel the tapeworm.

Scientists are now searching

for drugs among the plants

they believe chimps take as medicine.

We have long tested human drugs

on chimps

someday we may test drugs discovered

by chimps on ourselves.

Chimpanzee cultures also

mold their methods of communication.

Besides their calls,

they use a symbolic language

of gesture.

Some gestures we hold in common a

kiss soothes a little domestic discord.

Others we seem to recognize

two males clasp hands

and raise their arms in a salute

as they begin to groom one another.

Other gestures, such a leaf grooming,

we are only beginning to decipher.

When a chimp wants to be groomed,

they pick a leaf and just,

uh, run the thumbs over it,

sometimes bring a mouth to it

and then drop it.

What does this mean?

Well, in functional terms,

it means nothing,

but it's a symbol.

It's a symbol for the chimps.

What it means to them is

I would like to be groomed

or sometimes it means I'm interested

in you.

If these gestures are truly cultural,

we should be able to see them evolve

as fashions change.

Christopher Boesch believes he has.

Leaf-clipping is a behavior

where they take a leaf,

makes a specific sound

and in Tai they do it

before displaying.

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