We go over this rather extensively from time to time. And that's a very
good thing. What constitutes a difference in species is a bit amorphous,
not to mention what constitures a sub-species. We need a definitive
formula for discerning these differences. As yet, we don't have one. My
thinking is that the more we talk about it, the more likely siomeone is
to come up with deffinitions we can all live with. We are somewhat like
the Monkeys on the typewriter, knowing that, given enough time, we will
come up with the Compleat Wrks of Wm Shakespeare, Abridged.
        It took Mark Twain to describe Golf as "A good walk, ruined". Someone
out there will do the same for species.
        Art