 |
| Researchers who studied 144 chimpanzee communities in Equatorial Africa found 31 behaviors that varied from one group to another (AFP Photo/ISSOUF SANOGO) |
Washington (AFP) - Like humans, chimpanzees are culturally diverse but those differences are being eroded by human incursion, international researchers say in a groundbreaking study published Thursday.
The
striking results, published in the American journal "Science," show
that the behavioral diversity of chimpanzees was reduced by an average 88 percent
in areas with the highest human impact, compared to remote pristine forests.
In the
tropical rainforests and savanna woodlands that are the chimpanzees' natural
habitat, the researchers observed 31 behaviors that were not universal or
innate among chimpanzees and varied from one group to another, in a total of
144 chimpanzee communities studied in 17 Equatorial African countries where the
animals live.
Reflecting
the diversity, not all communities of chimpanzees use the same tools to hunt or
dig. Neither do they extract termites and ants in the same way. Ditto for honey
and nuts. Their use of stones, ponds and caves also varies.
Researchers
assume this diversity is passed between individuals within the group.
They based
their findings on existing studies supplemented with their own field
observations of 46 communities over the past nine years.
Such data
had never before been compiled on chimpanzee behavior, the researchers said.
Until now, scientists have focused on the loss of genetic diversity, or
human-caused population decline.
Their
findings mean that the more humans disturbed the environment with roads,
infrastructure, deforestation, agriculture, plantations and so on, the less
chimpanzee behavior was diverse.
For
instance, researchers have observed areas where nut cracking had ceased.
"These
are very noisy behaviors, and hunters could locate you easily," Hjalmar
Kuehl, an ecologist at the German iDiv research center and the Max Planck
Institute for Evolutionary Anthropology, told AFP as a hypothesis of why the
behavior may have been lost.
Another
example of noisy and potentially vulnerable behavior: "accumulative stone
throwing" by chimpanzees in Guinea-Bissau, a form of communication where
chest-pumping apes throw rocks at trees.
Fishing for
algae with sticks, seen in Guinea, is also threatened by encroaching humans.
"Our
findings suggest that strategies for the conservation of biodiversity should be
extended to include the protection of animal behavioral diversity as
well," said Kuehl.
He proposes
to create "Chimpanzee cultural heritage sites," a concept that can be
extended to other species with high degrees of cultural variability, including
orangutans or whales.
No comments:
Post a Comment