The next time someone calls you a “bird brain,” you may want to plant a big, fat kiss on their overgrown primate noggin.
Inch for inch, birds cram more neurons into their pea-size brains than primates do, new research suggests.
“For a long time, having a ‘bird brain’ was considered to be a bad thing: Now, it turns out that it should be a compliment,” Suzana Herculano-Houzel, a neuroscientist at Vanderbilt University in Tennessee, said in a statement.
That may explain how the feathery fliers are able to ace so many intelligence tests, the authors speculated.
Brain size matters
Early on, the scientific mantra when it came to animal intelligence was that size matters: The bigger the brain, the brainier the species. However, that notion had some gargantuan flaws, as elephants and whales have much bigger brains than humans, yet few scientists believed those animals were smarter than humans. Others attempted to explain animal intelligence in terms of the ratio of brain to body size. But this measure didn’t track perfectly with animal intelligence, either, as studies have demonstrated.
The most glaring exceptions are birds, such as crows and parrots, which have relatively large heads for their bodies, but very small heads overall. Numerous studies have shown that some birds can use tools, recognize themselves in the mirror, and anticipate and plan for the future. One particularly cerebral parrot, an African grey parrot named Alex, was even able to grasp the concept of zero.
Therefore, birds presented a mystery. Most birds have tiny heads…