Anecdotal evidence has long suggested that dogs hold an edge over felines when it comes to smarts, what with their record of service in military and police units and their history of assisting people with disabilities.
The analysis also discovered that the raccoon was an outlier-on the brainy side: It packs the same number of cortical neurons as a dog into a brain the size of a cat's. Carnivory is one of several factors expected to be cognitively demanding for carnivorans due to a requirement to outsmart larger prey.
She detailed those findings in a research paper, titled "Dogs have the most neurons, though not the largest brain: Trade-off between body mass and number of neurons in the cerebral cortex of large carnivoran species", which has been OK'd for publication in the journal Frontiers in Neuroanatomy.
What they found is that dogs have around 530 million cortical neurons in their brains versus just 250 million for cats (for comparison, humans have around 16 billion). Neurons are the cells that help with thinking, planning and other complex behaviors.
Other animals involved in the study include a ferret, mongoose, raccoon, hyena, lion and brown bear.
The researchers picked carnivorans to study due to their diversity and large range of brain sizes as well as the fact that they include both domesticated and wild species.More news: Oregonians contributed to Project Veritas, organization behind botched Washington Post sting
As it turns out the size of the brain is not what matters the most.
That means that it may take as much brain power to avoid being caught as it does to do the catching. Another oddity is the bear - its brain is about 10 times larger than a cats, but has a similar amount of neurons.
"I would bet money on a large dog over a cat any time", Herculano-Houzel said in a Vanderbilt-produced video.
The team were working on the theory that domesticated animals have smaller brains than their wild cousins, and that carnivores have bigger brains than herbivores.
Study leader Professor Suzana Herculano-Houzel admitted she was a "dog person" but insisted that didn't impact her findings.
"Diversity is enormous", said Houzel.