CHIMPANZEES are on their way to becoming half-decent chefs. Captive chimps in
Madrid have begun to pur茅e their own fruits and vegetables, in what looks
like the first case of an ape transforming food to improve its taste and
texture.
Chimps use all sorts of clever techniques to obtain food, such as fishing
termites out of mounds with sticks and bashing palm nuts open with rocks. But
these tricks do not alter the quality of the food. 鈥淭hese are not cases of
transformation of food in the human way,鈥� says Samuel Fern谩ndez-Carriba,
a primatologist at the Universidad Aut贸noma in Madrid. 鈥淭ransformation
involves things like grinding and heating.鈥�
The first chimp to perform the new trick was Linda, who was brought to the
university zoo in 1992 after her previous owner had removed all her teeth to
avoid being bitten. When she had been at the zoo about a year, the keepers
noticed she was managing to eat apples by rubbing them along a sharp corner in
her enclosure so that pulp and juice ran out on the wall. She would lick the
mashed fruit off the wall and then rub the apple some more. Six other chimps in
the same enclosure soon began to imitate her. Now the whole group, except the
alpha male and female and an infant, have picked up the technique.
Advertisement
Fern谩ndez-Carriba and his colleagues Angela Loeches and Ana Morcillo
have now watched the chimps pur茅eing their food for more than 450 hours.
Rather than just mashing up fruit any old way, the other chimps have adopted
Linda鈥檚 means of preparation. They all rub the fruit on a sharp corner for about
10 seconds and then lick off the pur茅e. Because the chimps copy the
action in a stereotypical fashion, the researchers conclude that it is a
culturally transmitted ritual. Chimps are known to have passed on around 40
other behaviours in the same way.
The gourmet chimps eat apples, carrots, lemons and oranges by rubbing, which
changes not only the texture but also the flavour of the food. And since they
choose to take the time preparing each dish, they may get greater enjoyment or
satisfaction from the result, says Fern谩ndez-Carriba.
It is unclear whether food transformation exists in the wild, he says. Either
we just haven鈥檛 seen it, or animals can鈥檛 afford to waste time preparing each
meal. 鈥淏ut if [like the chimps] you have the time, you might cook all day and
make something nice,鈥� Fern谩ndez-Carriba says. 鈥淢aybe this is one more
piece of evidence that we are not as unique as we previously thought.鈥�
