Dolphins and Whales Have Sophisticated Human-Like Societies

by Jen Viegas,

No one has ever been able to fully measure the intelligence of whales, dolphins, and porpoises, but evidence continues to mount that it is impressive. Consider Kelly, a dolphin formerly housed at the Institute for Marine Mammal Studies in Mississippi. She was trained to keep her outdoor tank clean. If she brought a piece of litter to her trainer, she was awarded with a fish.

The enterprising Kelly figured out that if she wedged a single piece of litter under a stone and ripped it into multiple pieces, she would receive more fish. She then determined that she could increase the amount of “litter” in the tank by using the earned fish as bait to catch unwary birds. She subsequently taught these clever strategies to her calf.

Dolphins like Kelly, along with whales and porpoises, all engage in sophisticated behaviors that tend to be mostly associated with humans. They live in tightly knit social groups, have complex relationships, communicate with each other using language-like vocalizations, and even have regional dialects.

New research links this complexity of cetacean culture and behavior to the size of their brains. The findings, published in the journal Nature Ecology & Evolution, position these marine mammals with humans and other primates in an elite and very brainy group.

“Each species’ brain is unique, but primates and cetaceans do share some features that are rarely found elsewhere in nature,” lead author Kieran Fox of Stanford University’s department of neurology and neurological sciences told Seeker. “One is the sheer size of their brains in absolute terms. They are the biggest in the world, and in the case of the whales, the largest brains ever to appear on the planet.”

“Additionally,” he continued, “primates and cetaceans both tend to have large brains relative to the size of their bodies.”

Co-author Michael Muthukrishna, a researcher at Harvard University and the London School of Economics and Political Science, explained that, in general, larger brains are able to store and manage more information than smaller brains. Braininess comes with a price, though, as such tissue is incredibly energetically expensive.

“The larger your brain, the more calories you need to support it, so actually you’re better off with the smallest brain you can get away with,” Muthukrishna said. “Bees are a nice example. They can do quite a lot with their small brains.”

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