It’s long been debated which is smarter – dogs or cats? Those in the dog camp claim that the ability to be trained makes man’s best friend the brainiest, while fans of felines argue that a cat’s nonchalance, independence, and high standards make it far superior. Cats were once worshipped as gods, after all.
However, science seems to have brought new evidence to the debate, something that will bring smug satisfaction to every “dog person”. It turns out that dogs have many more neurons in the cerebral cortex of their brains than cats. These special cells are associated with various signs of intelligence like thinking, planning, and complex behavior.
Published in the journal Frontiers in Neuroanatomy, the study didn’t just focus on our favorite pets. The international team of scientists looked at the brains of various carnivore species too. Interestingly, they found that only the smaller species – dogs and smaller – have higher densities of cortical neurons. Striped hyenas have fewer than dogs, for example, and brown bears have the same number as cats.
Meanwhile, raccoons, despite having small, cat-sized brains, have as many neurons as dogs, making them “comparable to primates in neuronal density”, and therefore rather smart. No wonder they can solve puzzles and are famed for being cunning thieves.
What’s more, domestication didn’t seem to have any effect on neuronal composition in the brains of the carnivores tested in the study.
"I believe the absolute number of neurons an animal has, especially in the cerebral cortex, determines the richness of their internal mental state and their ability to predict what is about to happen in their environment based on past experience," said study author Suzana Herculano-Houzel of Vanderbilt University in a statement.
The team found that dogs have around 530 million cortical neurons in their brains, while cats have just 250 million. For scale, humans have 16 billion. But before you get too smug about how smart people are, long-finned pilot whales have 37 billion. In fact, according to a 2016 article in Scientific American Mind, this “plays havoc with the notion that humans have more nerve cells where it counts than any other species on the planet”.