Basic evolutionary theory question.

A group of a species that is isolated from other members can adapt over
time, but is there any evidence about why the ancestors of this "new
species" are not able to breed with the ancestors of those other
members millions of years (or whatever) later?

Thanks.


.

Relevant Pages

  • Re: Poached: Is Lucy our ancestor?
    ... evidence and what we know. ... There is no evidence on which to base strong conclusions of ancestry, except for noticing the paraphyly of a biological species in the present day. ... Of course such relationships exist, though it seems unlikely, given the small proportion of species estimated to be preserved as fossils, that we actually have any examples of ancestors, even if we can't tell. ... no conceivable fossil evidence that would show one species to be ancestral to another, unless we knew somehow that we had a complete sample of all species in the taxon. ...
    (talk.origins)
  • Re: Poached: Is Lucy our ancestor?
    ... evidence and what we know. ... sequences of species. ... we actually have any examples of ancestors, ... identity of the great-grandfather in question. ...
    (talk.origins)
  • Re: Co-optation Today
    ... More like saying you are affirming beyond the evidence. ... many features connecting the species, ... know that penguins had flying ancestors without knowing the name of any ...
    (talk.origins)
  • Re: Basic evolutionary theory question.
    ... but is there any evidence about why the ancestors of this "new ... In the case of species which have diverged less, ... possibility is chromosome re-arrangements. ... You mentioned 'evidence'. ...
    (sci.bio.evolution)
  • Re: "Species"? Feces!
    ... one species cannot reproduce with members of another species. ... only random genetic mutations which result in the inability ...
    (sci.bio.evolution)