Dolphins learn from peers in similar way to humans and great apes, study discovers

Researcher says ‘surprising’ findings open new doors for further study of dolphin behaviour

Dolphins can learn foraging techniques from their peers in a similar way to humans and great apes, a new study has discovered.

Scientists had previously observed that dolphins’ mothers in Shark Bay, Western Australia, passed on techniques to their offspring — a phenomenon that is known as “vertical social transmission”.

However, it had been thought transmission between generations was the only way dolphins learned such methods.

Now, a new study published in the journal Current Biology has suggested dolphins learn a foraging technique called “shelling” by watching close associates and then adopting the method themselves — a phenomenon called “horizontal social transmission”.

Shelling is a technique used by dolphins when prey hides inside large empty shells of giant sea snails and involves them using their beaks to bring such shells to the surface and then shake the trapped food into their mouths.

The dolphins of Shark Bay have been closely-studied for more than 35 years and the method was first recorded by scientists in the mid-1990s.

Dr Sonja Wild, a postdoctoral researcher based at the Centre for the Advanced Study of Collective Behaviour at the University of Konstanz, said the findings were “surprising” and opened doors for further research of dolphin behaviour.

“These results were quite surprising, as dolphins tend to be conservative, with calves following a ‘do-as-mother-does’ strategy for learning foraging behaviours,” Dr Wild, who led the study, said.

“However, our results show that dolphins are definitely capable, and in the case of shelling, also motivated to learn new foraging tactics outside the mother-calf bond.”

She added: “This opens the door to a new understanding of how dolphins may be able to behaviourally adapt to changing environments, as learning from one’s peers allows for a rapid spread of novel behaviour across populations.”

The study provides further evidence of cultural similarities between dolphins and great apes, which have also demonstrated a broad range of socially-learned foraging behaviours.

“The fact that shelling is socially transmitted among dolphin peers rather than between mother and offspring sets an important milestone, and highlights similarities with certain primates, who also rely on both vertical and horizontal learning of foraging behaviour,” Professor Michael Krützen, director of the Department of Anthropology at the University of Zurich, said.

“Despite their divergent evolutionary histories and the fact they occupy such different environments: both dolphins and great apes are long-lived, large-brained mammals with high capacities for innovation and the cultural transmission of behaviours.”

Professor Krützen was a senior author on the study and has been studying social evolution of great apes and marine mammals for nearly 25 years.