Although today cats and dogs are the most popular companion animals, these are furry they are so different both externally and 'neurally'. Their survival strategy is very different: while some always remain in family groups with whom they can jointly catch prey, others have always been more solitary.
We might think that, because of this, the domestic feline is smarter, since it has to manage by itself to get its food and to stay alive, but a scientific study shows us that we are wrong. Dogs are smarter than cats because they have more neurons.
This is demonstrated by a study from Vanderbilt University: while cats have around 250 million neurons, dogs have 530 million. For comparison, the human brain has 16 billion. The scientists wanted to compare different species of carnivores to see how the number of neurons related to the size of their brains, including, in addition to cats and dogs, lions and brown bears.
The aim was to confirm the intuitive hypothesis that carnivore brains should have more cortical neurons than the herbivores they feed on, as hunting is more demanding. But they were shocked when they discovered that the ratio of neurons to brain size in small and medium carnivores was very similar to that of herbivores, which means that it is very possible that all of them have the same evolutionary pressure: the former to trap herbivores, and the latter to escape predators.
As a curiosity, they have also been able to find out that a Golden Retriever's brain has more neurons than a hyena, lion, or brown bear, despite the fact that they are predators whose brains are up to three times larger. Professor of Psychology and Biological Sciences and study author Suzana Herculano-Houzel said that "our findings mean to me that dogs have the biological ability to do much more complex and flexible things with their lives than cats."
Without a doubt, a topic that can be very popular with dogs. 
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