Yes. That's basically his entire theory.
Evolution by natural selection is an elegant, simple system. Variation is a species exists in every generation. No two individuals are the same. If some individuals can not survive in the environment, they die off. If they can, then they survive to pass on their genes and future generations will have the same traits as them. This happens over millions of years, and the changes build up and produce different species.
For example, imagine the world is cooling down, to the point where elephants can't survive in the cold. The more hair the elephants get, the more likely they are to survive. Now eventually as this goes on all of the elephants will have a thick layer of fur. Enter, woolly mammoth.
So yes. Environment directly shapes appearance, structure and every other trait.