Sn0wst0rm wrote...
I think that I see what you are saying now. For clarification, you are not asserting that species which evolved separately from us would be capable of interbreeding; merely, that it appears that it happened inside our evolutionary path?
Nope. But then again... *quick thought experiment follows*...even if you took a common evolutionary ancestor and distributed it across solar systems by some panspermic method like asteroid impact ejecta, the only organism capable of surviving that sort of transition would be fairly basic and single-celled, and even then evolution on the 'seeded' planet would probably be billions of years behind the host planet by the time the seeding has took place. So there'd be far too much room for evolutionary divergence, considering evolution has lots of random factors and not purely causal ones. There's always a vanishingly small chance that evolution could reconverge independantly if it shares a common ancestor, but probability just wouldn't support it.
If you take a Star Trek style aliens-playing-god artificial panspermia, far later down the evolutionary line (say, when hominid evolution has already kicked in) divergence will probably still occur into seperate hominid species, yet the Neanderthal example shows us that interbreeding might still be possible.
Hopefully that might answer the OP's question.
Modifié par shootist70, 26 août 2010 - 08:35 .