Washington, Mar 27 : Chimps make judgments about strangers' actions and dispositions by observing their behaviour and interactions in different situations, says a new research.
According to a new study, chimpanzees show an ability to recognize certain behavioural traits and make assumptions about the presence or absence of these traits in strangers in similar situations thereafter.
Primates have sophisticated social skills and there is evidence that they eavesdrop and benefit from third-party interactions.
In a series of three experiments, Dr. Francys Subiaul, from the George Washington University in Washington DC and colleagues looked at whether chimpanzees learn the reputation of strangers indirectly by observation, or by first-hand experience.
Seven chimpanzees observed unfamiliar humans either consistently give ('generous' donor) or refuse to give ('selfish' donor) food to either a familiar human recipient or another chimp.
In the first experiment, after observing humans either give or refuse food to familiar humans, chimps were in turn given the opportunity to gesture to either the 'selfish' or the 'generous' human, reports Springer News.
There was no marked preference for either donor. However, in a second experiment, the researchers evaluated whether prolonged observation and first-hand experience would allow chimps to generalize this social rule-pertaining to the reputation of strangers-to new humans. In this experiment, the chimpanzees showed a strong preference for the new generous donor.
They were able to predict which new donor was generous, based entirely on observation. In a third experiment, chimpanzees were the recipients of either 'selfish' or 'generous' acts.
The results of this last experiment replicated the results of the second experiment in a new context and using novel 'generous' and 'selfish' acts, demonstrated that chimpanzees are flexible and astute social problem-solvers, capable of attributing reputation to strangers by eavesdropping on interactions between others.
The results of the study demonstrate that chimpanzees' ability "to infer stability in an individual's character or behavior over time through observation - an inference that underlies the ability to make reputation judgments...This ability may have served as a catalyst to the evolution of various uniquely human traits such as shared intentionality, language and reasoning."
The study is published online in Animal Cognition, a Springer journal.