Dolphins have ‘human-like’ societies...but are held back by a lack of opposable thumbs, say scientists

Sarah Knapton
Bottlenose dolphins breaching from the water, Moray Firth, Scotland -
Bottlenose dolphins breaching from the water, Moray Firth, Scotland -

Whales and dolphins live in human-like societies and share similar brain evolution to primates and man, scientist have concluded.

A new study which looked at 90 species found a link between brain size and social and cultural traits in marine mammals.

It is the first time that scientists have considered whether ‘social brain hypothesis’ applies to whales and dolphins, as well as humans. The theory suggests that intelligence developed as a means of coping with large and complex social groups.

Just like humans, whales and dolphins live in tightly-knit social groups, cooperate with other species, talk to each other and even have regional dialects.

They also engage in cooperative hunting, and pass on their skills to younger members. Some even have signature whistles, which are believed to represent names, so they can call to individuals.

A pod of narwhal whales swim in the Arctic Ocean. - Credit: Stocktrek Images, Inc. / Alamy Stock Photo&#160;
A pod of narwhal whales swim in the Arctic Ocean. Credit: Stocktrek Images, Inc. / Alamy Stock Photo

The study showed it was possible to predict the brain size of intelligent marine mammals based on the complexity of their social and cultural structures.

The researchers conclude that, just like humans, whale and dolphin cognition may have arisen to cope with the challenges of social living.

Dr Susanne Shultz, an evolutionary biologist in the University of Manchester’s School of Earth and Environmental   Sciences, said: “As humans, our ability to socially interact and cultivate relationships has allowed us to colonise almost every ecosystem and environment on the planet.



“Unfortunately they won’t even mimic our great metropolisis and technologies because they didn’t evolve opposable thumbs.”


Encephalisation, underpins humans’ sophisticated social cognition, including language, joint attention, shared goals, teaching, consensus decision-making, and empathy.




Researchers say the findings could help scientists also understand more about how humans have been so successful.

Dr Michael Muthukrishna, Assistant Professor of Economic Psychology at LSE, added: “This research isn’t just about looking at the intelligence of whales and dolphins, it also has important anthropological ramifications as well.



The research was published in the journal Nature Ecology & Evolution.