Chimps 'feel death like humans'

Chimpanzees deal with death in much the same way as humans, studies suggest.

Scientists in Scotland filmed a group of chimps grooming and caressing an elderly female who died, and remaining subdued for several days afterwards.

Other researchers saw females carrying around the bodies of their dead children. Both studies are reported in the journal Current Biology.

The scientists say this suggests other species, particularly apes, are more like humans than we might think.

"Several phenomena have at one time or another been considered as setting humans apart from other species: reasoning ability, language ability, tool use, cultural variation, and self-awareness, for example," said James Anderson from Stirling University, who led the research team looking at the death of the elderly female.

"But science has provided strong evidence that the boundaries between us and other species are nowhere near to being as clearly defined as many people used to think.

"The awareness of death is another such psychological phenomenon."

Keeping close

Staff at Blair Drummond Safari and Adventure Park in Stirlingshire used video cameras to document the death of a terminally ill female named Pansy, believed to be more than 50 years old.

When she became lethargic in the days leading up to her death, other members of the group became quieter than usual and stayed with her at nights, grooming her more than they did normally.

After her death, her daughter stayed near the body for an entire night, even though she had never slept on that platform before.

All of the group were subdued for several days afterwards, and avoided the place where she had died, spending long hours grooming each other.

In the second study, led by scientists at Oxford University, two mothers living in the wild at the Bossou site in Guinea were seen to carry around the bodies of their dead children - one of them for nearly 10 weeks.

This behaviour has been seen once before at the site, in 1992; and the researchers suggest it may be learned.

During the period, the babies' bodies slowly mummified as they dried out. The bereaved mothers used tools to fend off flies.

Religious beliefs

"Our observations confirm the existence of an extremely powerful bond between mothers and their offspring which can persist, remarkably, even after the death of the infant," said Oxford's Dora Biro.

"They further call for efforts to elucidate the extent to which chimpanzees understand and are affected by the death of a close relative or group-mate.

"This would both have implications for our understanding of the evolutionary origins of human perceptions of death and provide insights into the way chimpanzees interpret the world around them."

Chimpanzees and humans share about 99% of their DNA, and are so closely related that some academics have suggested they should be given rights similar to human rights.

Dr Anderson suggests the treatment of death marks another similarity.

"We found several similarities between the chimpanzees' behaviour toward the dying female and their behaviour after her death, and some reactions of humans when faced with the demise of an elderly group member or relative, even though chimpanzees do not have religious beliefs or rituals surrounding death," he said.

Malignant malaria found in apes

The parasite which causes malignant malaria in humans has been identified in gorillas for the first time.                                                                        

Researchers analysed faeces from wild gorillas in Cameroon and blood samples from a captive animal from Gabon.

The study says increasing contact between humans and primates due to logging and deforestation raises the risk of transmission of new pathogens.

The research findings are published in Proceedings of the National Academy of Sciences journal.

New genetic sampling techniques allowed scientists from France, Cameroon, Gabon and the US to examine evidence of malaria parasites in the faecal matter of wild gorillas and chimpanzees in Cameroon.

"Sampling malaria parasites from apes in the wild has until now been very difficult", said Dr Francisco Ayala from the University of California, Irvine.

The team also took blood samples from wild born, pet animals in Gabon.

DNA evidence of Plasmodium falciparum, the parasite that causes malignant malaria in humans, was found in faecal samples from two gorilla subspecies, the highly endangered cross-river gorilla and the western lowland gorilla.

The parasite was identified in a blood sample from a captive gorilla.

Malaria parasites were first identified in chimpanzees and gorillas in Africa by scientists working in the 1920s.

But this new technology has allowed scientists to confirm the presence of P. falciparum.

Disease reservoir

P. falciparum is the most deadly type of malaria infection.

It is most common in Africa, south of the Sahara, where the World Health Organization says it accounts for a large part of the extremely high mortality in the region.

The study says that human destruction of the natural forest habitat means more contact with primates and greater chances of pathogen transmission between the two, including from humans to the endangered great apes.

Dr Ayala said the findings underline the danger of contact between the two. "Even if it were eradicated in humans we would still have the problem that it's present in apes and therefore they would be a reservoir for the disease.

"It's not clear what we can do with respect to this problem other than trying to decrease contact."

Endemic?

Dr Ian Hastings, senior lecturer at the Liverpool School of Medicine said it would help to know more about the spread of the parasite in gorillas.

"Mosquitoes often bite different species. Often they have a preference but if they can't find what they want to bite they'll just go and bite something else," he said.

"The question is whether this is just sporadic infection that's come from humans after the mosquito bit an infected person and passed it on to gorillas or whether it's endemic and is passed from gorilla to gorilla."

Dr Ayala acknowledges that Plasmodium parasites are much less malignant for apes than humans because primates have been exposed to them for so long.

"They have had P. reichenowi and perhaps other species for thousands or millions of generations, so one expects less malignancy to have taken place over time."