Question for knowers of scientific things, if a more primitive form of life is more survivable than a?

Question

more advanced on, for whatever reason in a given area, or even equally survivable, can a Species devolve to resemble a previous evolutionary stage? I guess in my mind I am thinking about whales and dolphins coming to resemble fish again. So my question is, how is it known that all hominids are becoming less apelike and more man like, and some are not examples of taking a step to more apelike features because for whatever reason, those features make him more survivable? (A heavy skull and brow ridge, for example)

I was thining of this because I read Neandertal brains were larger than nours, but they had heavier bones and more muscular physiques. How do we know which came first?

Answer 1

Well, evolution does not care about primitive or simple or complex or any of those terms. The only thing that matters is the survival of the species. There is no 'devolve'.
Species change
The changes either promote or hinder the survival of the species.
The changes die out or continue.

The whole idea of 'apelike' being more primitive is incorrect from an evolutionary standpoint. There is no goal, no drive, to become 'manlike'.

Answer 2

humans were survivable because of our superior intellect, not physical adaptations, so i doubt we will return to ape like animals. Possibly if we will change i think it will be very drastic and caused by some kind of holocaust.