Size doesn’t matter
How can we measure an animal’s intelligence? To begin with, researchers decided to first look at the ratio between the size of the brain and the size of the animal. For example, big brown bears and cats have quite a similar brain size, but the anatomic differences might give you the impression that cats are more intelligent than their honey-eating friends.
But this criterion is still very rough, and scientists quickly started looking into other factors which allowed them to realise that both cats and bears have quite similar cognitive abilities since they have a similar number of neurons.
The concentration of neurons gives the advantage
To understand the development of carnivores’ brain capabilities, researchers looked into the concentration of neurons in the brain (more specifically in the cortex). From ferrets to mongooses, including hyenas and even lions, researchers assumed that the more neurons an animal has, the higher the level of cognitive ability.
This approach was judged effective by Suzana Herculano-Houzel, a neuroscientist at the University of Vanderbilt in the United States.
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 based on past experience.
Based on this principle, researchers discovered that dogs possess on average 530 million neurons in comparison to the 250 million that cats have. This result indicates that dogs have a much larger intelligence, closely followed by our friend the raccoon.
And what if intelligence is determined by the owner?
There is also the question of whether the number of neurons is enough of a factor to determine whether cats or dogs are more intelligent in practice. Maybe at the end of the day, it comes down to the individual and past experiences, because no matter the cognitive capabilities, what matters the most is what your pets do with them and how they interact with their master is the most important factor. And while we’re talking about intelligence, don’t forget that there isn’t just one form of intelligence, but eight!