Real species and ideology

[Curtis Clark]

At 11:45 2004-04-20, Richard Pyle wrote:
>How would you distinguish the two separate patterns (morphocline of
>subspecies vs. introgressive hybridization) -- even with the best of genetic
>tools?  Indeed, is there anything fundamentally different between the two
>patterns, other than our artificial imposition of the rank "species" in one
>case, and "subspecies" in another?

They differ in the process that gives rise to them. In the first case,
there was never a full cessation of gene flow. In the second, it stopped,
and then started. Of course one could imagine a continuum between the end
cases, but the end cases surely exist. And just because we don't currently
have the methodology to measure or characterize something, that doesn't
mean that it isn't improtant.

>This gets right to the heart of my original question to you, about defining
>the terms "real" and "artificial" in an evolution/species context, and in
>supporting one perspective over the other.

That's a road best not taken. Something is "real" if scientists can study
it from different angles and get consistent results. The philosophical
issues are interesting in their own right (my degree does say *Ph*D, after
all), but I don't see that they directly affect what we do as scientists.


--
Curtis Clark                  http://www.csupomona.edu/~jcclark/
Web Coordinator, Cal Poly Pomona                 +1 909 979 6371
Professor, Biological Sciences                   +1 909 869 4062