Evolutionary neuroscience is the study of how the brain and nervous system have evolved in different animals over time. It examines the structure, development, and function of the nervous system in order to understand how various features have been adapted in different species. For example, some species have developed bigger and more complex brains than others, which could explain why they are more intelligent or better at certain tasks. By looking at evolutionary trends, scientists can learn more about how the brain works and how it can be used to help humans.