If a, say a Blastoise, has eggs, wouldn't you get a baby Blastoise? I mean, it says Pokemon evolve, and not grow. Wouldn't it also be logical to have an adult Bulbasaur? Etc.
no, eveolution is a selective translation of a word meaning metamorphisis, for some reason kids have a hard time saying it, and so eveolution is easier.
I see where your coming from, but pokemon evolution is different from Darwins theory. Its more of growing up or metamorphisis, so its logical to have the basic stage.