[DManA]

Should we then be surprised that other species stay unchanged for 100's of millions of years?

[Stultis]

Should we then be surprised that other species stay unchanged for 100's of millions of years?

There are no known species that have remained unchanged for 100's, or even 10's, of millions of years. Crocodiles, coelacanths, horseshoe crabs, etc, are were very similar in the very ancient past to forms currently living (and I think in the later two cases -- somebody correct me -- may even belong to the same genera) but they are not the same species.

[Quick1]

Not if there is no need for them to change.