Dipping for Ants

New research has shown that West African chimpanzees follow the long-held carpenter’s credo: “The right tool for the job.” It appears the chimpanzees will go far and wide to find the shrub that grows the perfect branches needed to both “dig” and “dip” for army ants without being painfully bitten.

Hunting for Ants

As reported in the American Journal of Primatology, the chimpanzees use a set of two tools specifically constructed from the Alchornea hirtella shrub to hunt the army ants. Chimpanzees use the first tool to “dig” into the nest to aggravate the ants. They then use the second tool to “dip” into the nest so the ants will gather onto the stick, which then allows the chimpanzee easy access to some “finger food.”

“Ant dipping is a remarkable feat of problem-solving on the part of chimpanzees,” said lead researcher Dr. Kathelijne Koops from the University of Cambridge’s Division of Biological Anthropology. “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. But by using a tool set, preying on these social insects may prove as nutritionally lucrative as hunting a small mammal – a solid chunk of protein.”

A Cultural Perspective

The research is a part of the scientists’ greater effort to study chimpanzee culture, particularly how chimpanzees learn and pass on tool making for ant dipping to younger chimpanzees.

“Scientists have been working on ruling out simple environmental and genetic explanations for group differences in behaviors, such as tool use, and the evidence is pointing strongly towards it being cultural,” Dr. Koops said. “They probably learn tool use behaviors from their mother and others in the group when they are young.”

Other studies have shown the importance of mothers in the development of young male chimpanzees and the intricacies of how chimpanzees choose their friends.

“This study is part of a big ongoing research project,” Dr. Koops said. “The next stages will involve looking at social opportunities to learn: how much time do youngsters spend within arm’s length of other individuals; how much time do they spend close to their mother; as well as innate predispositions to explore and engage with objects.”