CHARLOTTE, NC (WBTV) - Which is smarter - a cat or a dog? A new study may be shedding some light on an old argument that's had pet owners fighting like, well... you know.
The study, published in Frontiers in Neuroanatomy, focuses on the number of neurons (cells associated with thinking, planning and complex behavior - considered hallmarks of intelligence) in the cerebral cortex of several carnivores, including cats and dogs.
"In this study, we were interested in comparing different species of carnivorans to see how the numbers of neurons in their brains relate to the size of their brains, including a few favorite species including cats and dogs, lions and brown bears," wrote Associate Professor of Psychology and Biological Sciences Suzana Herculano-Houzel.
According to the study, dogs have significantly more neurons than cats - about 530 million compared to about 250 million.
"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," Herculano-Houzel explained.
"I'm 100 percent a dog person," she added, "but, with that disclaimer, our findings mean to me that dogs have the biological capability of doing much more complex and flexible things with their lives than cats can. At the least, we now have some biology that people can factor into their discussions about who's smarter, cats or dogs."
According to Vanderbilt University, where the study was conducted, the researchers "expected that their measurements would confirm the intuitive hypothesis that the brains of carnivores should have more cortical neurons than the herbivores they prey upon." That's based on the idea that hunting prey is more demanding than the herbivore's lifestyle.
That, however, proved to be wrong. Turns out, according to the study, the ratio of neurons to brain size in small and medium-sized carnivores was about the same as herbivores.
That means that it may take as much brain power to avoid being caught as it does to do the catching.
The study also suggests that the ratio of neurons to brain size is lower for larger carnivores.
For instance, the study states, "the brain of a golden retriever has more neurons than a hyena, lion or brown bear, even though the bigger predators have brains up to three times as large. The bear is an extreme example. Its brain is 10 times larger than a cat's, but has about the same number of neurons."
The paper also noted that raccoons have about the same number of neurons as dogs, even though their brains are the same size as cats.
"Meat eating is largely considered a problem-solver in terms of energy," said Herculano-Houzel "but, in retrospect, it is clear that carnivory must impose a delicate balance between how much brain and body a species can afford."