A social brain is a big brain
DOLPHINS BECAME SMART SAME WAY HUMANS DID
Dolphins may have humans matched on almost every other prerequisite for planetary dominance, but they can’t finish the job because they lack hands.
“Unfortunately, they won’t ever mimic our great metropolises and technologies because they didn’t evolve opposable thumbs,” said Susanne Shultz, an evolutionary biologist at the University of Manchester.
Schultz is an author on a new study finding that dolphins’ social behaviour is basically an aquatic version of human society. Along with other whales, dolphins give themselves names, have language dialects, raise children as a group and care for their elders.
“Many cetaceans (whales, dolphins and porpoises) are also organized in hierarchical social structures and display an astonishing breadth of cultural and prosocial behaviours,” reads the study.
Published in Nature Ecology and Evolution, the study was not meant to gauge dolphins’ fitness for global domination. Rather, it’s a neurological study meant to figure out how humans got so smart in the first place.
The researchers were probing what’s known as the “social brain hypothesis,” a 20-year-old theory holding that humans evolved their giant brains as a result of living in complex social groups.
In the high school-like dynamics of a prehistoric tribe, cleverer members were more likely to have sex, keep the tribe safe and generally avoid getting their heads bashed in.
While other animals lived in simple pecking orders, early humans dwelled in a complex political world of alliances, manipulation and co-operation. As a result, goes the theory, the human species was organized in such a way that it favoured the quick evolution of increasingly witty members.
This is opposed to, say, lobsters, where being a charismatic genius doesn’t have quite the same genetic returns.
By analyzing the social dynamics of whales and dolphins, researchers hoped to find out if cetaceans might be locked in a similar cycle of evolving ever-giant brains due to their convoluted social lives.
The researchers profiled a cross-section of cetaceans and assigned them a “social repertoire” score based on the sophistication of how they organized themselves. If a whale species had ever shown the ability to predict the mental states of others, for instance, their score got a boost. Baleen whales, by contrast, had their scores docked for speaking languages that were much more simplistic than orcas or dolphins.
Scientists then controlled for other possible brain-enlarging factors such as geography or the richness of the animals’ diet.
Their conclusion was that the more complicated a whale’s social life, the smarter they became.
“Our analyses demonstrate that cetacean brain evolution is best explained by the demands associated with maintaining and coordinating cohesive social groups,” it read.
Interestingly, whales weren’t particularly smart when, 50 million years ago, their dog-like ancestors first returned to the sea. It was only after forming into sleek aquatic mammals and banding into complex pods did the animals transform into the superintelligent beings we know today.
According to the study, it is no accident that large brains, “cohesive social bonds” and a penchant for complicated political manoeuvring all seem to occur in the same species.
Lead author Kieran Fox, a Stanford University neurologist, said in a statement that scientists have often concluded that dolphin brains are not sophisticated to handle the “higher cognitive and social skills” of human society.
“I think our research shows that this is clearly not the case,” he said.