JUST as immigrants adopt the accent of the country that they move to, so
chimpanzees copy the local customs when they join another group. It shows that
chimps have culture, say William McGrew and Linda Marchant at Miami University
in Ohio and their colleagues.
The researchers found that wild chimps learn specific hand gestures. 鈥淚t鈥檚
like the boy scouts having a three-finger salute and the cub scouts having a
two-finger salute,鈥� says McGrew.
Many social scientists maintain that humans鈥攚ith our language, fashion
and music鈥攁re the only animals sophisticated enough to have culture. But
biologists are now arguing that animals such as apes, dolphins and whales have
complex behaviour that they learn from each other. This, they argue, is a form of culture
(快猫短视频, 24 March, p 26).
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McGrew and his team were studying the chimps鈥� grooming hand-clasp. In some
groups, when two animals meet they join left or right hands above their heads as
they start grooming. Unlike many other differences in chimp behaviour, such as
variations in food gathering, the hand-clasp appears to have no practical
function, so it is likely to be a purely social gesture.
The researchers discovered that two neighbouring groups of the primates in
the Mahale Mountains National Park in Tanzania had slightly different forms of
the gesture. One group used a palm-to-palm grasp, while the other group favoured
a wrist-to-wrist grip. But when the researchers looked at a series of
photographs of these groups of chimps taken over the past 35 years they
discovered something remarkable. Individuals that had migrated from one
community to the other dropped their old style of hand clasp and took up the new
one. The researchers now want to see how long it takes for the chimps to change.
鈥淲hen we see that kind of nuance in human behaviour, we call it culture,鈥� says
McGrew.
