It’s official: dogs are smarter than cats
Counting brain cells reveals the average cat has fewer than half as many as a dog.
Your cat is not enigmatic and given to philosophical pondering. It is just dumb – at least compared to a dog, which on average has more than twice the number of neurons in the cerebral cortex, the brain’s thinking centre. That’s about 530 million neurons compared to 250 million.
Humans have about 16 billion – so their number and density is a proxy for intelligence. This means dogs have the biological capability to do much more complex and flexible things with their lives than cats, says neuroscientist Suzana Herculano-houzel of Vanderbilt University in Nashville, Tennessee.
In the study “Dogs have the most neurons, though not the largest brain”, Herculano-houzel and her colleagues counted the neurons of eight carnivorous species to test the hypothesis that carnivores have more developed brains than herbivores. The animals studied were cats, dogs, ferrets, mongooses, raccoons, hyenas, lions and brown bears.
The theory stems from the assumption that hunting prey is more cognitively demanding than munching plants.
This idea – almost a touchstone of evolutionary theory – did not hold up. Published in the journal Frontiers in
Neuroscience, the study found that small to medium-sized carnivores had about the same number of neurons as their herbivore prey – suggesting the evolutionary pressure to out-think a predator is at least the same as out-thinking prey.
The big hunters have big brains but a lower ratio of neurons to brain size. The brown bear has about the same number of neurons as a cat, in a brain 10 times bigger. A lion has fewer neurons than a golden retriever, in a brain three times the size.