On Sun, 1 Oct 1995, Erich Schwarz wrote:
> it would be something like getting a fertile hybrid between _Homo sapiens_
> and a tarsier.
>
Very true, and I'm sure that my imagination is more limited then most!
As with the turtles there are physical limitations that would prevent
hybridization (We don't ever expect to see a Ridly [small sp.] X
Leatherback [huge sp.] -- although think of how much fun we could have in
the literature if we did!). Many of the threads that have been
expressed on this topic are very true:
1) divergence does not necessarily = reproductive isolation
2) reproductive incompatibiltiy does not necessarily = genome wide
divergence (although I do believe that if two organisms are
reproductively isolated then if we don't call them species now we will
in the future).
3) _reproductive compatibility_ is a plesiomorphic character.
4) species status can (and should?) be assigned based upon a variety of
characteristics. How about this -- is two organisms are
reproductively isolated then they are two species. If not, and there are
other characteristics (ecological, behavioral, etc.) that clearly delineate
the organisms then they are two species.
for whatever it is worth,
Steve
Stephen Karl
Department of Biology
University of South Florida
4202 East Fowler Ave, LIF 169
Tampa, Florida 33620-5150
Voice (813) 974-1592
Fax (813) 974-3263
EMail Karl at .chuma.cas.usf.edu
