Dogs Smarter Than Cats, But Felines As Smart As Bears: Study

It probably doesn’t settle much in the minds of people fighting like, well cats and dogs, over which pet is smarter, but a study published last month says dogs are brainier than cats — although you probably already knew that if you’ve tried to train a feline to do tricks or, really, almost anything you wanted the cat to do.

The reason your cat won’t do what you want is that felines only have about 250 neurons in their cerebral cortexes, less than half the number that dogs have. The neurons are associated with thinking, planning and complex behavior, Suzana Herculano-Houzel, an associate professor of psychology and biological sciences at Vanderbilt University, said in the study, published this month in the journal “Frontiers in Neuroanatomy.”

But, cheer up, cat lovers. Cats and brown bears have similar smarts, even though bears’ brains are about 10 times larger, according to the study. Researchers studied eight species of carnivoran — a diverse order that consists of 280 species of mammals that have teeth and claws needed to eat other animals. Species studied included ferret, mongoose, raccoon, hyena and lion, in addition to cats, dogs and brown bears.

The neuron-to-brain size is actually lower in the largest carnivorans. The researchers found that a golden retriever has more neurons than a hyena, lion of brown bear, even though the other animals’ brains are up to three times larger than the dog’s.

The researchers’ findings blew their hypothesis right out the window. They expected to find more cortical neurons in carnivores than in the herbivores they prey upon, because hunting is more demanding, cognitively speaking, compared to the herbivores’ primary strategy of finding safety in numbers.

Instead, they found the number of neurons were about the same in small- and medium-sized carnivores as in herbivores. That suggests herbivores are under just as much evolutionary pressure as carnivores to develop the brain power to escape the predators trying to catch them, Herculano-Houzel and her team said.

“Meat eating is largely considered a problem-solver in terms of energy, but, in retrospect, it is clear that carnivory must impose a delicate balance between how much brain and body a species can afford,” Herculano-Houzel said in a statement about the study.

Hunting is tedious work, particularly for large, meat-eating predators. For example, lions spend most of their time just laying around. That’s because the brain is, in terms of energy, the most expensive and its requirements are proportional to the number of neurons, the researchers said.

Brains also need continuous energy, and as a result, the amount of meat large hunters can kill and consume and the amount of time they spend resting seems to limit brain development, the researchers said.

The study also challenged the assumption that domesticated animals like cats, dogs and ferrets have smaller brains than wild carnivores because they don't have to work hard to find food. But there wasn’t much difference in the brain-size-to-body-weight ratio between pets and the other animals in the study.

Researchers also discovered that raccoons are an outlier. Their brains are about the same size as a cat’s, but they have the same number of cortical neurons as some of our closest cousins.

“Raccoons are not your typical carnivoran,” said Herculano-Houzel said. “They have a fairly small brain but they have as many neurons as you would expect to find in a primate — and that’s a lot of neurons.”

The study was funded by the James S. McDonnell Foundation; the Schapiro Undergraduate Research Fund at Randolph-Macon College; the Vice Deanship of Research Chairs at the King Saud University; the National Research Foundation of South Africa; and Brazilian crowdfunding contributors.

(AP Photo/Jeff Roberson)