Science. Which animals are smartest. Dogs, cats or raccoons.

Science

Which animals are smartest: Dogs, cats or raccoons?

By Jason Bittel, Washington Post, adapted by Newsela staff

Text Level:6

Cat people and dog people have long sparred over which species possesses the best brains.

Team Cat points to the felines' self-reliance as a sign of intelligence. The animals can hunt, which isn't so great for wildlife but does showcase the cunning predator still lurking within lap kitties. Cats also clean themselves and relieve themselves in tidy litter boxes — or even toilets. They are generally better at food portion control than their canine housemates, too.

Team Dog cites the canines' ability to learn complex tasks, especially those that benefit humans. Dogs guide the blind and herd livestock. They sniff out explosives and help find survivors buried beneath earthquake rubble. They also have strong memories and an impressive capacity to understand human language.

But as it turns out, all of this résumé listing may be unnecessary. According to a new study published in Frontiers in Neuroanatomy, the best way to measure cognitive ability is to tally each animal's neurons.

Neurons are cells that communicate via electrical charge. They populate the brain and central nervous system. They are the units that process information. Measuring intelligence is an incredibly difficult affair. But Suzana Herculano-Houzel, a Vanderbilt University neuroscientist, and her colleagues believe their method of quantifying neurons in an animal's brain, especially in the cerebral cortex, is the most accurate tool for judging its capacity for complex thought.

So which animal comes out ahead in the Great Neuron Census? Brace yourselves, Team Cat.

"Dogs have about twice as many neurons as cats," said Herculano-Houzel. She is the author of a book about brains called "The Human Advantage."

But wait: The average dog is larger than the average cat. Isn't it a given that dogs would have larger brains and therefore more neurons? This is where things get interesting.

The study found the overall mass of one's gray matter is not what's important. In addition to the dog and cat, the team examined brains from a domestic ferret, a banded mongoose, a raccoon, a striped hyena, an African lion and a brown bear. While the brown bear's brain was three times as large as the dog's, the dog's had more neurons. In fact, the brown bear's neuron count was similar to that of the cat, an animal whose brain is about 10 times smaller.