March 23, 2005

Trunk Call: Elephants Learn to Mimic

PARIS (AFP) -- African elephants have an excellent ear for imitation, say biologists who have recorded tuskers copying the roar of passing trucks and the chirpy sounds of zoo stablemates.

Mlaika, a 10-year-old adolescent female elephant living among semi-captive orphaned elephants in Tsavo, Kenya, imitated trucks as they passed her stockade, even though it is three kilometers (1.8 miles) from the nearest road, the researchers report in Nature, the British science weekly.

Calimero, a 23-year-old male African elephant who spent 18 years with two female Asian elephants in an enclosure in Switzerland's Basel Zoo, proved to be a dab hand at imitating their characteristic chirping calls.

Spectrogram analysis shows that the audio frequency of the two elephants' imitations are spot-on.

Various other animal species, such as birds, bats and dolphins, have long been known to be able to learn new vocalisations.

With this discovery, elephants have the honour of becoming the first terrestrial mammal after humans to be known to have the skills.

The study was led by Peter Tyack of Woods Hole Oceanographic Institution, Massachusetts, and Joyce Poole of the Amboseli Elephant Research Project in Sandefjord, Norway.

The authors suggest that thanks to mimickry, elephants are able to identify themselves distinctly to friends within a shifting social group.

"It is a useful form of acoustic communication that helps to maintain individual-specific bonds within changing social groupings."