EDINBURGH, Scotland, May 23 (UPI) -- Chimpanzees and orangutans really do have personalities "like people," British researchers say.
The new findings address a long-standing debate about whether great apes possess human-like personalities or if such perceived behavior is an anthropomorphic projection of human observers, they said.
Using a statistical method to remove any biases in human observers of apes' behavior, researchers at the University of Edinburgh in Scotland said their study suggests humans and apes really do share "personality dimensions," the BBC reported Wednesday.
"[Chimpanzees] have the same social problems that we do. They want to make friends and find mates and sort of gain position within their society," said Mark Adams, who conducted the research while studying for his doctorate at Edinburgh.
Alexander Weiss, a senior lecturer at the university who also worked on the study, agrees that chimpanzee personality is "highly similar" to that of humans.
Researchers categorize human personality into five "dimensions," he said. "Those dimensions are neuroticism, extroversion, openness to experience, agreeableness and conscientiousness."
The shared personality dimensions between chimps and humans are likely due to genetic similarities, Weiss said.
"Humans and chimps share a common ancestor about 4 [million] to 6 million years ago."
The research "vindicates both the view that chimpanzees have personalities and perhaps the more controversial statement that their personalities are quite similar to those of humans," Weiss said.