Analysis of Whale Sounds Uncovers Evidence of Culture
Sperm whales are the deepest diving mammal in the world's oceans. They have the largest brain on the planet. And now, new research suggests that they use unique sets of clicks and sounds to separate themselves into distinct "clans."
All sperm whales draw on a small selection of morse-code-like clicks called "codas," but the combinations of patterns differ from group to group. Researchers have found that these sounds separate sperm whales in the Pacific into five distinct groups or clans. The immediate question this rose was: Are these differences in codas determined by genetics or learned culture.
To test this question, researchers collected samples of discarded skin from whales across the ocean. When these samples were analyzed, they found something surprising: Whales with different coda patterns often shared similar genetics. This means that the sound patterns are learned within social groups.
"All the evidence for culture relies on methods of exclusion. It's very difficult to actually prove cultural transmission," explained Luke Rendell a scientist at the University of St Andrews who led the study, "but our finding isn't consistent with anything other than cultural dialects."
The finding—which implies behavior in marine mammals in culturally determined—could have implications for conservation efforts focused on whales and other species.