Image makeover: A five year study of bonobos in the Democratic Republic of Congo observed them hunting other primates on at least five occasions.
Credit: Wikimedia
Human implications
Over five years of observation the researchers have now seen three instances of successful hunts in which bonobos captured and ate their primate prey. In two other cases, the bonobo hunting attempts failed.
The data from Salonga National Park showed that both bonobo sexes play active roles in pursuing and hunting monkeys. The involvement of adult females in the hunts (which is not seen in chimps) may reflect social patterns such as alliance formation and cooperation among adult females, they said.
Overall, the experts argue that the discovery challenges the theory that male dominance and aggression must be causally linked to hunting behaviour, an idea integral to earlier models of the evolution of aggression in human and non-human primates.
Hohmann said that future work may shed light on the social and ecological conditions that encourage bonobo monkey-hunting expeditions, yielding insight into the evolutionary significance and causes of aggression in both these apes and our own species.
Alarming decline
Another study published this week in Current Biology reports a drastic decline in the West African sub-species of chimpanzee (Pan troglodytes verus) living in Ivory Coast.
Researchers led by Geneviève Campbell, also of the Max Planck Institute for Evolutionary Anthropology, found that the population had fallen by a staggering 90 per cent since the last survey was conducted 18 years ago.
The alarming decline in a country that had been considered one of the final strongholds for West African chimps suggests that their status should be raised to critically endangered, says the study, which cites a growing human population and civil war as the likely cause of the demise.
With Cell Press/Current Biology.
