Tightly knit families and groups of friends. Alliances toward specific goals. Teaching each other hunting techniques. If these sound like human behaviors to you, you’re not wrong – but they’re not. Whales and dolphins form human-like societies with complex relationships and culture, according to marine biologists.
In a new study, scientists found that Cetaceans generally have intricate societies complete with social play, transfer of knowledge, and even “dialects” in their vocal communication. Some of the whistles and chirps common in whale and dolphin song may even be names, the biologists said.
More complex societies appear to be linked to brain size in proportion to the whales’ or dolphins’ bodies, they said.
Humans have long known that whales and dolphins have elaborate cultures, said Dr. Susanne Shultz, an evolutionary biologist at the University of Manchester. But the insight into their behaviors and how they influence whales’ and dolphins’ human-like societies has added a new layer to the understanding of how intelligence evolves.
“That means the apparent co-evolution of brains, social structure, and behavioural richness of marine mammals provides a unique and striking parallel to the large brains and hyper-sociality of humans and other primates on land,” Shultz said. “Unfortunately, they won’t ever mimic our great metropolises and technologies because they didn’t evolve opposable thumbs.”
The team, from the University of Manchester, Stanford University, the London School of Economics and Political Science, and the University of British Columbia, gathered information about 90 different species of whales, dolphins and porpoises. With that information, they created a database documenting cooperative behaviors and other aspects of the Cetaceans’ social structures.
They used the datasets to test evolutionary hypotheses about the social brain and cultural brain, two ideas proposed to explain the evolution of human society and intelligence in other land mammals.
The team of researchers found that the theories appear to apply to marine mammals as well.
“This research isn’t just about looking at the intelligence of whales and dolphins; it also has important anthropological ramifications as well,” said Dr. Michael Muthukrishna of the London School of Economics and Political Science. “In order to move toward a more general theory of human behaviour, we need to understand what makes humans so different from other animals. And to do this, we need a control group. Compared to primates, cetaceans are a more ‘alien’ control group.”
The research may also offer clues into how certain behaviors crop up in some animals but not others – especially as Cetacean brain structures are not very similar to those of land mammals.
Those different brain structures led some scientists to theorize that dolphins and whales couldn’t develop higher cognitive skills, let alone human-like societies, said Dr. Kieran Fox of Stanford.
“I think our research shows that this is clearly not the case,” he said. “Instead, a new question emerges: How can very diverse patterns of brain structure in very different species nonetheless give rise to highly similar cognitive and social behaviors?”
The team’s study has been published in the journal Nature Ecology and Evolution.