A female chimpanzee (right) uses a blade of grass to clean the teeth of a deceased group member Edwin J. C. van Leeuwen, Katherine A. Cronin & Daniel B. M. Haun

For the first time, a chimpanzee has been observed using tools to clean the corpse of a deceased group member. This behaviour could shed light on the evolutionary origins of human mortuary practices.

A female chimpanzee, Noel, at Chimfunshi Wildlife Orphanage Trust in Zambia sat down by the dead body of a young male, Thomas, whom she had previously adopted. She then selected a firm stem of grass, and started to intently remove debris from his teeth. She continued doing this even after the rest of the group had left the corpse.

A team of scientists from the University of St Andrews, UK, who observed the behaviour think this could mean that the long-lasting social bonds that chimpanzees form continue to influence their behaviour even after their bonding partner has died.


“The report is important because it indicates once more that the human species is not the only one capable of compassion,” says Edwin van Leeuwen, lead author of the study.

It appears that chimps, like humans, treat deceased members of their own species sensitively, rather than treating them like inanimate objects – especially when the deceased is a close associate.

“This is certainly an interesting and noteworthy observation, another case of chimpanzees showing unusual behaviour in the presence of deceased group members,” says Klaus Zuberbuehler, also at St Andrews, who wasn’t involved in the study. “We have seen similar behaviour in our wild group of chimps in Budongo forest, Uganda, where individuals groomed an adult female, who had just been killed, for an extended period of time.”

The behaviour could also show that chimps are curious about death and mortality. The team thinks this could tell us something about how human mortuary rituals began.

However, Zuberbuehler cautions that it is near impossible to draw any meaningful conclusions about underlying mental processes or awareness from these kinds of observations. “Perhaps, such social behaviour is a manifestation of human-like mourning, perhaps the chimpanzees are just challenged by the fact that a group member has suddenly become completely motionless,” he says.

Thibaud Gruber of the University of Geneva, is also cautious about interpreting this as chimps understanding death.

“We simply do not know if and how much chimps understand about death,” he says. “In other words, it is unclear whether this is ‘corpse cleaning’, or simply ‘social cleaning’. But certainly, it adds on behavioural descriptions of unusual behaviour displayed by chimps when they face the death of one of their species.”

Journal reference: Scientific Reports, DOI: 10.1038/srep44091

Read more: How chimps mourn their dead; Chimps beat up, murder and then cannibalise their former tyrant; Gang of chimpanzees kills their alpha male