Different sperm whale ‘dialects’ detected on separate sides of the Mediterranean

From “Howdy” to “G’day”, English – like other languages – is rich in dialects. Now researchers have found sperm whales on different sides of the Mediterranean show similar variations in their vocalisations. Sperm whales communicate vocally using sequences of short clicks called codas. However, the rhythmic pattern of these clicks, known as the dialect, can differ between different matriarchal groups. Crucially, one group of sperm whales will only associate with another if they share the same dialect and hence belong to the same “vocal clan”. “The dialect is used to form social structures, within which these animals will cooperate,” said Dr Luke Rendell, of the University of St Andrews and a co-author of the new study, noting similarities in how humans might be more comfortable striking up a conversation with someone who sounds similar to themselves. Now Rendell and colleagues say they have discovered two different dialects among Mediterraean sperm whales – a small, endangered population of a few thousand individuals that are thought to have first entered these waters about 20,000 years ago. What’s more, they say the finding offers new insights into how sperm whale dialects arise. Writing in the journal Proceedings of the Royal Society B , the team note genetic studies have previously suggested Mediterranean sperm whales have become isolated from other sperm whales. …