Subspecies

[DR. JAMES ADAMS]

Listers,

	Okay, I promise this is the last time!

	It is clearly just a matter of degree, and quite subjective, as to 
what *anyone* decides should be called a subspecies or not.  
Perhaps Cris and I are not quite as far apart as we seem.  I am not 
suggesting necessarily that subspecies should treat each other as 
*completely* distinct entities -- I agree with Cris that if this is the 
case, then probably two species are involved.  But both Ken and I 
have made the point that if the differences are extremely minor, and 
there is no evidence one way or the other whether genetics or 
environmental influence or some combination thereof are involved in 
establishing the difference, then you're jumping the gun in 
describing new subspecies.  To me, if there are *no* genetic 
differences between populations, then you are dealing one entity -- 
period.  Again, there is very little of this type of work that has been 
done when naming subspecies, which is why I still dislike the way 
the concept is used.  Yes, it would require a lot of work, but this is 
no excuse for taking the easy way out!!  However, Ken's (and Cris'!) 
idea of naming geographic segregates does have it's place, and 
certainly can be useful when trying to pass information on (what, 
did I really just say that?!).  But let's not call different populations 
"subspecies" when what we really mean are simply geographic 
segregates, with no knowledge of the genetics or evolutionary 
history of the populations involved.  This is where Ken's idea really 
has merit.
 
Cris also wrote:
>  If "the *populations* treat each other as something distinct"
> as James suggests, the odds are very good that two species are
> involved.  I can't off-hand think any subspecies which have what I
> would call significant biological differences. Perhaps James can
> provide some examples.

Again, I wasn't necessarily indicating that the populations would 
not mate at all, or not even necessarily have significant intermating 
or other social interaction.  Treating something as distinct could be 
something as small as some different behavioral characteristic, or 
larval foodplant, etc.  And, yes, I can think of some generalized 
examples (though I would have to go back and review specific 
papers from those seminar classes I had in college over ten years 
ago!!) -- certain bird subspecies and slight differences in calls,etc..  
I don't remember which birds or subspecies, but I do remember 
slightly reduced, but certainly not eliminated gene flow between 
subspecies.  And I could give a number of plant examples, but I 
don't know that we want to go into species/subspecies boundaries 
in the plant world!!

		James

Dr. James K. Adams
Dept. of Natural Science and Math
Dalton State College
213 N. College Drive
Dalton, GA  30720
Phone: (706)272-4427; fax: (706)272-2533
U of Michigan's President James Angell's 
  Secret of Success: "Grow antennae, not horns"