(July 17, 2017 at 11:59 pm)snowtracks Wrote: Even evolution theory recognizes that land mammals returned to the sea. Why did marine mammals go back to the sea? http://www.pbs.org/wnet/nature/ocean-gia...tion/7577/Why did I sometimes go back to ex-girlfriends? Sometimes the supply of pussy available in my environment was inadequate.
Seriously, though, if you are asking this, you don't know what evolution is. Evolution doesn't mean "improving toward an ultimate archetype." It means "coming into conformity with the pressures of the environment."
The environment changes, so the qualities which are selected by evolution change-- so species change.