London, Jan 27 (ANI): Just like humans, chimpanzees too need a best friend, says a new study, which has found that adult male chimps form enduring social bonds with other males, exchanging back scratches, sharing meat, and generally chumming around.
According to John Mitani, a primatologist at the University of Michigan, who observed chimpanzees in Uganda several months a year for 10 years, these bonds lasted seven years, reports New Scientist.
In the jungles of Kibale National Park, the colony is about three times the size of other chimpanzee populations in Africa, but is no more social than others, the researchers said.
To reach the conclusion, Mitani spent a block of time recording the interactions of a specific adult male chimp, including every individual he interacted with, while noting grooming behaviour.
Females tend to leave their colony once they reach maturity and therefore forge fewer social bonds, Mitani says.
As far as human friendship is concerned, the strongest bonds seemed to be based on mutual respect. Chimpanzees that groomed each other for roughly equal amounts of times tended to stay friends longer.
Fraternity too played a crucial role in chimpanzee friendships, Mitani found.
Animals that shared a mother were more likely to form lasting bonds than other pairs. Almost every chimpanzee that research team tracked formed at least one long-term social bond, and some had multiple "best friends". Out of 35 males, two never formed close friendships with other adults during the study period. However, both found friendship in a younger, still adolescent brother, Mitani notes.
However, what makes chimpanzees form these stable bonds is unknown, Mitani says.
The study has been published in the journal Animal Behaviour. (ANI)