Ask someone to think of an animal, and chances are they’ll come up with one of our relatives among the mammals. A few people might go further afield and mention other vertebrates, like birds and fish.

We're going to take a closer look at brains, how animals use them, and how some animals have even evolved to lose them! It turns out a brain (and intelligence more broadly) isn't easy to define, but ...

Your nervous system is a network that sends signals between your brain and other parts of your body to control your body's movements and processes. This system includes your brain, spinal cord, and ...

The sympathetic nervous system, which helps your heart and other vital organs function all the time, increases activity in response to danger or stress, preparing the body for extra demands. Stress is ...

The parasympathetic nervous system (PSNS) is one of two major divisions of the larger autonomic system in your body. Its function is to keep the basic functions of your body working as they should.