Dennis wrote:

> I agree basically with your last statement. But did Bob really argue about
> the flickers? The hybrid zone between yellow-shafted and red-shafted is
> *huge*, and I can show you breeding flicker specimens from Washington that
> show hybrid characters. So many hybrids come into our collection here that
> I envision flickers to the north and east of us as one huge hybrid swarm.
> Gilded and red-shafted hybridize over a much narrower zone, not surprising
> as they are somewhat separated ecologically, and it's also not surprising
> that the gilded will be split off from the Northern Flicker. But
> separating yellow-shafted from red-shafted--I doubt it.

Commenting as a non-ornithologist, I am puzzled by the apparent behavioral
differences that are used to separate non-human animals into different species.
What I understand Dennis to be arguing is that the degree of hybridizing
that takes place is a critical factor in lumping or splitting species, not
whether the offspring of hybrids are fertile (the "old" method). So, explain
why it is that grizzly bears and polar bears (or is that Grizzly Bears and
Polar Bears?) *can* produce fertile offspring from interbreeding but *choose*
(not trying to anthropomorphize, just classify as behavior) not to, and thus
are considered separate species (even under the "old" method; biological
system somethingoranother).

I'm assuming it is valid to bring into the debate how non-ornithology
biologists separate species, or is this confusing the issue? Is there a
lack of agreement across disciplines (as in common name capitilization
conventions)? And, finally, are there other reasons than hybridization
behavior that cause yellow-rumps to be lumped?

--
Michael Patrick
University of Washington Medical Center
Department of Radiation Oncology, RC-08
1959 NE Pacific St.
Seattle, WA. 98195
mike at radonc.washington.edu
(206) 548-4536