Jun 15, 2016

Sperm whales exhibit cultural component to their lives

New ways to grab dinner, the trick to using a tool, and learning the local dialect. These are behaviors that animals pick up from each other. Killer whales, chimpanzees, and birds seem to have a cultural component to their lives. Now a new study suggests that sperm whales should be added to that list.

The ocean around the Galápagos Islands hosts thousands of female sperm whales and their calves that have organized into clans with their own dialects. (Mature males congregate in colder waters near the poles.) How these clans form has been something of a mystery until now.

A study published recently in the journal ‘Nature Communications’ suggests that culture—behaviors shared by group members—keeps these sperm whale clans together. Specifically, these deep-diving whales have a distinct series of clicks called codas they use to communicate during social interactions.

Sperm whales with similar behaviors spend time together, and they pick up vocalizations from each other. Scientists call this social learning. Whales that "speak the same language" stick together, giving rise to the clans that researchers have observed for more than 30 years.

This is one more pillar of support for the idea that animals have culture, says lead study author Mauricio Cantor, a marine biologist at Dalhousie University in Halifax, Canada.

When Cantor and colleagues ran computer simulations to determine the most likely way the clans formed, factors like genetic relatedness or the transmission of information from mother to offspring couldn't explain the pattern observed in the wild. The best explanation their analysis could find was a preference in how sperm whales learned vocalizations. "Like-minded" individuals learned from each other.

It's fascinating to see that animals like whales display something that may seem uniquely human, Cantor says. But really, "we're not that different from them."

Killer whale pods have their own dialects, humpback whales pass on new feeding behaviors via their social networks, and chimpanzees share the secrets of tool use with their compatriots. 
(Adapted from National Geographic magazine 2015)