Mongooses who can, teach

Can animals teach? Not quite, but mongooses have provided the first definitive evidence that young animals learn the ropes by imitation.

Biologists have long debated whether animals learn skills from each other, as they could also be inherited genetically or shaped by the environment. Now a study of wild banded mongooses (Mungos mungo) shows that pups copy skills from "teenage" males who act as escorts.

Mongooses have two ways of breaking bird eggs: by holding and biting, or by smashing them against rocks. Corsin Müller and Michael Cant of the University of Exeter, UK, gave an artificial egg containing food to smasher and biter escorts as their respective pup companions watched.

Two to four months later, the pair gave eggs to the pups. They almost exclusively used the same technique as their escort.

Passing on traditions

The researchers say that the experiment is the first to show in the wild that skills, or "traditions", are passed on through imitation of older role-models. "I avoid the term teaching, because the pups are copying the techniques they observe," says Müller.

Since the two skills co-exist in the same population, environmental and genetic explanations can be ruled out, says Michael Krützen of the University of Zurich in Switzerland, who observed bottlenose dolphins using sea sponges as tools.

"This shows beyond reasonable doubt, in my opinion, that contextual imitation plays an important role in the social transmission of behaviours," says Krützen.

One implication of this experiment is that such social learning could be far more widespread in nature than is appreciated, says Müller, who is now at the University of Vienna in Austria. This is particularly true since such learning was presumed to be restricted to species deemed more intelligent than mongooses, such as chimpanzees, dolphins and crows.