From: Bill Lucy 

In article , bobcomer{at}mindspring.com says...
> > So the fertile offspring of a horse and a donkey is the same species?
>
> There are so very few fertile that your guess is as good as mine.  And a
> bigger question is if  it's a natural cross anyway. (would it happen in the
> wild and would it be viable)

I really did think of leaving hinnies (the fertile cross) out, since it's
one in a million.

> > Mule deer and whitetail deer?
>
> I never heard of a cross between those two, natural or man assisted?

Because they don't generally share the same range, it doesn't happen often.
But it does happen. Naturally.

> > Xiphophorus maculatus, Xiphophorus helleri, and Xiphophorus vaiatus are
> > the same species?*
>
> Something I've actually kept myself, and those 3 are *extremely* closely
> related, and it could probably be argued that they are indeed the same
> species with some slight variation.  They don't usually choose to crossbreed
> (even among different color schemes of supposedly the same species), but
> they aren't against the idea either. 

This is where the rubber meets the road, as it were. Are they different
species, according to science? I'm not the expert, but fish taxonomists
have placed them as different species, and I'll leave it at that.

I've only used some examples, BTW. I'm waiting for Gary's response, because
there's more to the story regarding speciation by breeding.

--- BBBS/NT v4.01 Flag-5