Chimpanzees who spend time with humans when they are young have issues adjusting to live with their peers later in life.
Those who were removed from their mothers early in life and raised by humans as pets or performers are likely to show behavioural deficiencies as adults, scientists say.
The results of a study into 60 chimpanzees suggest that those raised primarily around humans with less experience around their own species during the first four years of life, tend to show reduced social competencies as adults.
They tended to engage in less social grooming with their group mates, a critically important behaviour for social bonding in chimpanzees.
These effects were expressed years, sometimes decades, after their lives as pets and performers were over.
It is legal in most of the United States to own a pet chimpanzee.
Steve Ross, director of the Fisher Center for the Study and Conservation of Apes at Lincoln Park Zoo, says chimpanzees are intelligent and sensitive animals.
“Denying them access to members of their own species, during the critical infanthood period, results in behavioural outcomes that last a lifetime,” Dr Ross says.
“Even with the best possible care as adults, they often can’t fit in with the other chimpanzees.”
The results of the study are published in the journal PeerJ.
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