777 次の交支を鞍み、下記の設半に等えなきい>
One of the most obvious of the chbimpanZee'g girnilaritieg with mnan iS hie brain.
The chimpanzee has an outstanding ability for basic reasoning. And man'e
intelhigence is closer to the chimpanzee's 人han to any other creature. In 色ct, the brajn
of the modern chimpanzee is probably not unjike the brajn of the 丘rst men
many millions of years ag0-
-CYeatur68,
Ancient man made tools, and we used to think that his made him 中作erent from
other creatures一until 1 frst watched two chimpanzees 五shing for white ants wi仙
]engths of grass. When most people think of tools, they think of man: and whenever
any animal can use an object as a tool, we have always shown special interest in it.
But this abihity does not necessarily mean the creature has any speoial
which could not be solvedl at all without a tool.
At the Gompbe Stream, we have seen chimpanzees use objects for mmany different
purposes. They use grasses and sticks to catch and eat insects: and 下the mmaterial is
not suitable, they change in some way. They use leaves to take up water-and frst
they chew the 1eaves so they wi山 hold more water. One chimpanzee used leaves to
clean out the last remains of brain from a baboon's skull*. We have seen them use |
jandfuls of leaves to rub dirt from their bodies, or to dry up wounds.
So far, no chimpanzee has managed to use one tool to make another. One |
chimpanzee was tested again and again、She was taught to use a sharp blade to break |
jittle bits o伴 a piece of wood: these bits could then pick food out of a narrow pipe.
She could do this when she could break of bits with her teeth. She was shown
the use of the blade many times, but she never even attempted to use t for the
problem. However, many other chimpanzees must be tested一we cannot be sure that
erform this. Some humans can do mathematics一others 4 |
* baboon's skull: ヒヒの頭骸骨
