Subspecies

[DR. JAMES ADAMS]

Chris,

> I have never understood why those who dislike the concept would care
> enough to attack those that do find subspecies meaningful.
> Unfortunately I still don't.

You are way too sensitive!  I'm not attacking those who find 
subspecies meaningful; indeed, I'm not even necessarily saying 
that subspecies have no place in taxonomy at all.  But there *are* 
those who have, as far as I can tell, named "subspecies" with little 
or no reason other than the entity looks a *little* different, or its 
simply found in a different place.  *This* is what I object to -- no 
*biologically relevant* reason for the name.  Contrary to what may 
have come across from my previous tirade, I use subspecific 
names myself, for entities which seem to be good vicariant entities. 
More about this below.

QUESTIONS: (1) What do you mean by "truly something
> different"? Obviously subspecies will not have major differences by
> definition, they are all the same species by definition. 

Agreed, to a point.  But this is my main objection in the first place.  
Unless I am mistaken, subspecific names *should be* applied to 
represent an entity which are biologically distinct in some way, and 
may potentially have it's own evolutionary path to follow.  
Otherwise, the names are nothing other than a human 
convenience, and may not represent a truly *distinct* taxon.

(2) What do
> you mean by "truly genetically differentiated"? How different is
> "truly" genetically differentiated?

There *is* no standard, obviously!!  Otherwise, we wouldn't be 
having this discussion!!

 (3) Why should subspecies mean
> "anything important evolutionarily"? Do species mean anything
> important evolutionarily? 

These are the only taxa which potentially *do* mean something 
important evolutionarily.  I'm sorry if I was using generalized jargon,
 but I thought it was pretty clear that I was talking about "natural"
 ("real"?) entities here.  Species within genera, families, etc. care
 nothing about what's happening evolutionary to other specific 
members of those higher level taxa -- each species has its own
evolutionary potential, independent of others.  Genera and all higher 
taxa are purely a matter of convenience for workers to indicate 
some level of relatedness, and clearly subjective.  Species and 
subsets thereof are the only entities upon which evolution can 
actually work, because these are the entities which are, by 
definition, still genetically unified in some way.  This is what I was 
referring to when I said "important" -- if the subspecies concept is 
going to be useful, it should apply to subsets of species which, 
although not distinct enough to be called species, have some 
genetic potential independent of other subspecies.  I'm sorry if it 
sounds to general, but I'll leave it at that for now. 

(4) British Columbia has been almost 100% recolonized by
> butterflies after the last glaciation, because it was nearly
> completely covered by ice. The geographic arrangement of subspecies
> provides information regarding the location of populations outside the
> province during the glacial period, and the pattern of recolonization
> of the province by butterflies specifically and plants and animals in
> general. It also indicates something of the evolutionary time required
> for isolated demes to diverge to a consistently different phenotype
> and (once tested through rearing) genotype. Is this "important"
> information? The same information could of course be eventually
> obtained through protein or (once refined) DNA analysis, at great cost
> for the same detail of geographic pattern, and at some indefinite time
> in the future. It could be argued of course that there is no need to
> apply a subspecies name to the phenotypically distinct groups of
> populations, but there is a definite advantage in being able to use
> one word to clearly indicate a phenotype that is being discussed.

I don't disagree here at all. However, I should probably let Ken 
Phillip answer this one.  He has an idea about population naming 
that I think is a great compromise. I doubt it will catch on, but it is 
a good idea.  Basically, give whatever population you want an 
appropriate geographical indicator name -- one word will suffice and 
let you know without looking at any label where the bug comes 
from.  I'm sure Ken will correct me if I've screwed up the idea. Sorry 
to put you on the spot, Ken!!  

>  Of course, some people
> name subspecies for the "glory" of it. Personally I name subspecies so
> that I have a single word which defines a distinctive deme,

Then you *did* understand what I was saying all along!!  Chris, you 
sly devil you!  Since you bombarded me with questions, then I'll 
ask you one, just what do you mean by "distinctive", hmm?  Chris' 
statement represents what I would consider *appropriate* use of 
the subspecies concept.

> Regardless of the motivation for naming a subspecies, a subspecies
> name results in increased ability to communicate about geographic
> variation below the species level.

Again, I don't necessarily disagree here, but the geographic 
indicator name idea would seem to be even more useful, instead of 
naming some subspecies after some person.
 
 QUESTION: So what?
> There are many subjective decisions in systematics, at all taxonomic
> levels. Why should subjectivity at the subspecies level invalidate
> that concept, when subjectivity at the species and generic levels does
> not invalidate those concepts.

Subjectivity will always be a problem with systematics, and there 
will always be disagreements because of it.  Again, my attack was 
perhaps a little too vehement the first time around.  I don't disagree 
with you here.
 
> "There may be a storm coming as well -- with our increasing ability to
> be able to pick populations apart at the molecular level, I can see a
> point where every little molecular difference may be used to say "hey,
> here's another subspecies (or species)."
 QUESTION: Again, so what? How
> does this invalidate the subspecies concept any more than the species
> concept?

Again, I agree, this doesn't invalidate the concept as a whole.  I 
would only disagree with this usage!!

> QUESTION: Why do you interpret the recognition that a species consists
> of many phenotypically distinct demes, by attaching a subspecies name
> to each, as being something highly negative?

You, of course, are correct here.  I have had my views slanted by a 
couple of genera.  The two genera I mentioned, Speyeria and 
Euphydryas, have been tremendously split.  I've had many 
discussions with people about western Euphydryas (Checkerspot 
butterflies), and several have mentioned that a number of the 
applied subspecies names seem to be relatively arbitrary.  With as 
much variation as exists *within* populations, it seems quite 
useless (to me)  to have subspecies named whose modal individual 
might be marked slightly differently, but whose variation totally 
encompasses that of another population.  This is just my opinion; 
you may think differently.  And it also bothers me that more 
subspecies are being named without complete knowledge of what 
other subspecies names may actually apply to.

	Chris, if names are just supposed to represent geographic 
demes, then I guess I can't disagree with much of anything you've 
said here.  I personally believe, however, that subspecies should 
represent entities that are relatively (hey James, what do you mean 
by "relatively") isolated from one another.  If gene flow is 
widespread among several populations on different mountaintops, 
in different valleys, etc., then I *don't* think calling them different 
subspecies is appropriate, because to me, this is a 
*misrepresentation* of the actual circumstance in nature.  For 
many species, not much is known in many species about vagility 
and gene flow between populations, certainly not to the extent to 
merit calling all sorts of different populations subspecies without 
further study.
 
> Given some time, we'll probably get around to splitting a bunch of the
> moths as well, whether they deserve it or not! QUESTION: How could or
> could not moths "deserve" anything. What criteria do you use for
> "deserving" splitting?

No offense, Chris, but this was a joke.  Remember those?  I've 
already made it clear that in some cases, splitting may be quite 
useful, wherease in others, it's not.
 
> SUMMARY: In your entire response there is not a single statement of
> fact demonstrating that recognition of subspecies is undesirable.

You yourself agreed that some people do throw names out there in 
the case of vanity that are unjustified.  I also hopefully made it 
clearer above why *oversplitting* ("overrecognition") could be very 
undesirable.

 Your
> entire response is a series of opinions.

I didn't say otherwise.

>  I have (above) provided a clear
> demonstration that recognition of subspecies is a useful biogeographic
> tool, please provide a clear example where it hinders some aspect of
> science.

I hopefully have taken care of my rationale to satisfy you, Chris!

	Keep keeping me on my toes, Chris!

		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"