How chimps learn to use hunting tools

Chimpanzees use tools to hunt ants and they probably learn tool use behaviours from their mother and others in the group when they are young, finds research.

"Scientists have been working on ruling out simple environmental and genetic explanations for group differences in behaviours, such as tool use, and the evidence is pointing strongly towards it being cultural," said Kathelijne Koops from University of Cambridge in Britain.

West African chimpanzees search far and wide to find Alchornea hirtella, a spindly shrub whose straight shoots provide the ideal tools to hunt aggressive army ants, the findings showed.

The plant provides the animals with two different types of tool, a thicker shoot for 'digging' and a more slender tool for 'dipping'.

"Ant dipping is a remarkable feat of problem-solving on the part of chimpanzees," Koops pointed out.

"If they tried to gather ants from the ground with their hands, they would end up horribly bitten with very little to show for it," she explained.

Koops set up cameras to take extensive video footage of the chimpanzees and their tool use.

In doing so, she managed to capture a chimpanzee who has constructed a tool with which to investigate the camera itself - prodding it curiously and then sniffing the end of the tool.

A video clip from the Kalinzu Forest in Uganda captured a male chimpanzee seemingly looking on enviously at a female who has managed to construct a much better dipping tool than his own and is feasting heartily as a consequence.

This kind of observing of other individuals may lead to learning within a chimpanzee community, Koops suggested.

The study appeared in the American Journal of Primatology.