Like humans, pilot whales form cliques, each with a distinct dialect that keeps the group exclusive.
Amy Van Cise at the Woods Hole Oceanographic Institution in Massachusetts and her colleagues sailed off the coast of the Hawaiian Islands, recording calls from short-finned pilot whales (Globicephala macrorynchus). Over a three-year period, the researchers recorded nine groups of pilot whales occupying the same area.
Analysis of the whales’ social calls showed that each group had its own signature call pattern. The researchers suggest that whale cliques might use these ‘dialects’ in part to maintain group identity and cohesion. Such cliques are known to be genetically distinct, which means that recording whale dialects could help researchers to track genetic diversity in this species, the authors say.