LONDON — Rare video footage taken at a wildlife park has showed that chimpanzees react to the death of a group member just like humans do when a close relative dies, researchers said Monday.
Videos of a group of four chimpanzees at Scotland's Blair Drummond Safari and Adventure Park showed three of the animals caressing and grooming the fourth, a dying female, more than usual, said James Anderson, a lecturer in psychology at Scotland's University of Stirling.
The videos also showed that the three chimpanzees tested the elderly female, Pansy, for signs of life at the moment of death, Anderson said. Pansy's daughter lay near her mother's body throughout the night, and all the chimpanzees were subdued in the next few days.
"It's the first time to our knowledge that people have been able to capture on video the precise moment at which an adult chimpanzee dies in the midst of his or her group," said Anderson, who co-authored a study to be published Tuesday in the journal Current Biology.
Researchers have not been able to observe how chimpanzees react to death because in the wild, a dying animal usually isolates itself and crawls into cover for protection, Anderson said. In zoos, sick animals are usually separated from the group and euthanized.
Staff at the Scottish wildlife park anticipated Pansy's death and recorded the group's behavior with overhead video cameras, which had been placed above the animals' sleeping platforms for a previous study.
The three surviving chimpanzees — all of whom had been living with Pansy as a group for more than 20 years — gathered around her and caressed her in the 10 minutes preceding her death. When she died, they inspected her mouth and lifted her head and shoulder to try to shake her into life, Anderson said.
The animals stopped grooming Pansy and left her after her death, although her daughter later came back to build a nest and lie by her all night long.
Alasdair Gillies, the head keeper at the park and co-author of the study, said the animals were quieter than normal and lost their appetites after the death.
"I think this video footage showed the chimpanzees were aware something strange and different was happening but other research will have to be conducted to see how much they understood what was going on. We are just opening the debate," he said.
The researchers said the study suggested that chimpanzees — known to have a developed sense of self and empathy toward others — were more like humans than previously thought.
"We were careful to avoid anthropomorphism, but it became very difficult not to realize some of these things are strikingly similar to human responses to dying individuals," Anderson said.