Evolutionary developmental biology, or "evo devo," is a broad term that involves a lot of different stuff. A lot of people use the term in a lot of different ways, so it makes it kind of difficult to understand; especially when it differs from scientist to scientist. But basically, evo devo is understanding how development is tweaked in a species over evolutionary time. It shows us what’s behind evolution and the slight changes that were actually involved. Only just recently, science as a community has gotten to a point where we actually can start to understand how genes make an embryo formed the way it does, how it makes what forms form uniformly from organism to organism within that species, and why that arm, or leg, or any other body
