PHOENIX — Dog people have long known that canines are smarter than felines. The fact that there are no service cats or drug-sniffing cats making that abundantly clear. 

A new study proves it beyond a biological doubt, giving dog owners the neuroscientific evidence they need to end the argument.

Jesse went through assistance dog training at Gentle Hearts Service Dogs and now belongs to a student with autism at Pieceful Solutions - Chander Campus. The charter school is for students with autism. The 18-month old Golden Retriever attends classes with the student and interacts with all students during recess.

Researchers at Vanderbilt University found that a dog’s cerebral cortex contains more than twice the neurons of a cat’s brain.

Neurons are cells associated with thinking, planning and complex behaviors, thus strongly related to intelligence.

And dogs have it way over cats in the neuron department.

Vanderbilt neuroscientist Suzana Herculano-Houzel (full disclosure: an avowed dog person) said canines have roughly 530 million cortical neurons, while felines have about 250 million.

(For comparison’s sake, human brains contain 16 billion, so don’t count on your dog pouring you a beer anytime soon.)

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Herculano-Houzel released the findings in a paper studying the number of neurons in a variety of carnivores, which was accepted for publication in the journal Frontiers in Neuroanatomy.

The Vanderbilt associate professor also studied the brains of a ferret, mongoose, raccoon, hyena, lion and brown bear.

“I would bet money on a large dog over a cat any time,” Herculano-Houzel said in a Vanderbilt-produced video. “They have the biological capability of doing much more complex and flexible things with their lives than cats can.”

Neuroscience now backs general knowledge, but history is filled with anecdotal evidence that dogs are smarter than cats.

Dogs have served in the military and in police K-9 units. When it comes to involvement with first responders, cats need help from firefighters to be rescued from trees.

Dogs assist people with disabilities and can learn to execute complex tasks. Cats generally stay out of the way. 

Famous dogs such as Lassie, Rin Tin Tin and Air Bud earned accolades for performing expert tricks on cue. Grumpy Cat gained fame for a singular facial expression.

With that said, cats still hold one edge: They know what a litter box is and how to use it.