Media release

From: University of Otago

Whale clans use vocalisations to mark their culture

What does whale culture look like – or rather, sound like? An international team of scientists, including Marta Guerra, Steve Dawson and Liz Slooten from Otago University, have just answered this question. Sperm whales use patterns of clicks called ‘codas’ to identify cultural groups. Like human ethnic groups, sperm whales use symbolic markers of cultural identity. 

Sperm whales communicate with Morse code-like series of clicks called ‘codas’, and whales that use similar coda dialects belong to the same cultural group or ‘clan’. Sperm whale researchers have long suspected that whales use certain coda types to distinguish vocal clans. But previous studies of sperm whale clans only looked at whales in one area at a time.

This work was the culmination of decades of research efforts by scientists working throughout the Pacific Ocean. The Otago University team made sound recordings of sperm whales off Kaikoura and Tonga. Then they worked together with scientists from Canada and the Netherlands, to learn something new about this enigmatic, charismatic, and cultural animal.

The team set out to investigate whether certain sperm whale codas are similar to human ethnic markers—such as dialects or clothing styles. They were specifically interested in ‘identity codas’; coda types that are particular to a clan, rather than common across clans.

Could such codas be symbolic markers of sperm whale clan identity? If so, they might mirror human patterns, where cultural groups are most marked or distinguishable in regions where several groups overlap—perhaps to better signal their group identity. In the same way, sperm whales rely on identity codas more in areas with many overlapping clans.

Whales from different clans never interact with each other, even when they share the same waters. This suggests that the whales have some way of distinguishing “us” vs. “them”, and we found out that they do so using identity codas. The whale dialects followed the pattern predicted from human culture. As spatial overlap between clans increased, their dialects became more distinct.

Our results demonstrate that culture structures whale populations, just as it does in humans.

These whale clans differ not only in the sounds they use, but also in how they move, forage, and socialise. This matches another human ethnic marker prediction: that symbolic marker and social norms should correspond.