Subspecies

[Cris Guppy & Aud Fischer]

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.

"As far as I'm concerned, numerous butterfly species have been *oversplit*,
with little biological evidence presented that the different populations
that have all been named are truly genetically differentiated to the point
where they are truly something different.  Sure, maybe the maculation on the
wings is a little different in this population, or the shading on the
underside of the hindwings is a slightly different tone, but does this mean
anything important evolutionarily?"
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.
(2) What do you mean by "truly genetically differentiated"? How different is
"truly" genetically differentiated?
(3) Why should subspecies mean "anything important evolutionarily"? Do
species mean anything important evolutionarily? Genera? How do you define
"important" anyway?
(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 believe a lot of the splitting has to do with vanity -- people *like*
seeing their names in print.  (Flame away!)". 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, rather than needing to
repeatly state "the segregate that occurs in the Chilcotin District of the
province of British Columbia, Canada". Regardless of the motivation for
naming a subspecies, a subspecies name results in increased ability to
communicate about geographic variation below the species level.

"If something is truly isolated genetically from other populations so that
it is on its own evolutionary path, then its only a matter of degree, and
completely subjective, as to whether to call the "entity" a subspecies or a
different species completely."
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.

"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? Botanists have long ago addressed the
issue of "molecular species" anyway. Many plant species (and subspecies) are
composed of genetically isolated genotypes with different chromosome
numbers, with the genotypes maintained as distinct evolutionary units
because hybrids are sterile. Botanists simply continue to recognize
phenotypically defined species while acknowledging that there is more than
one genetic lineage within a "species" or "subspecies".

"All you have to do is pick up a copy of the recently published book, *The
Systematics of the
>Butterflies of Western North America* (or something like that) to see that
the butterflies have been subspecified to death (check out the genera
Speyeria and Euphydryas)!!"  "Some butterfly species have been split to
death".
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?

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?

SUMMARY: In your entire response there is not a single statement of fact
demonstrating that recognition of subspecies is undesirable. Your entire
response is a series of opinions. Please supply a clear rationale
demonstrating that recognition of subspecies is detrimental to science (or
anything else). 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.

-----Original Message-----
From: DR. JAMES ADAMS <JADAMS at em.daltonstate.edu>
To: leps-l at lists.yale.edu <leps-l at lists.yale.edu>
Date: January 25, 2000 10:58 AM
Subject: Re: Subspecies


>Listers and Xi,
>
> I was wondering when this thread would get started.  I have
>some very strong *opinions* on this subject, but will try to keep my
>own rhetoric to a minimum.
>
>> Over the years, I've noticed that most butterflies are divided up into
>> quite a few subspecies, while most moths have no such division.  So,
>> is the reason for this lack of subspecification due to the fact that
>> butterflies are studied more than moths . . .
>
>The answer to this is an absolute "yes".  All you have to do is pick
>up a copy of the recently published book, *The Systematics of the
>Butterflies of Western North America* (or something like that) to
>see that the butterflies have been subspecified to death (check out
>the genera Speyeria and Euphydryas)!!  As far as I'm concerned,
>numerous butterfly species have been *oversplit*, with little
>biological evidence presented that the different populations that
>have all been named are truly genetically differentiated to the point
>where they are truly something different.  Sure, maybe the
>maculation on the wings is a little different in this population, or the
>shading on the underside of the hindwings is a slightly different
>tone, but does this mean anything important evolutionarily?  I
>believe a lot of the splitting has to do with vanity -- people *like*
>seeing their names in print.  (Flame away!)
>
> I actually have a problem with the subspecies concept as a
>whole.  If something is truly isolated genetically from other
>populations so that it is on its own evolutionary path, then its only
>a matter of degree, and completely subjective, as to whether to call
>the "entity" a subspecies or a different species completely.  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)."  Hopefully,
>scientists doing this work will do so with some reason, and not call
>every separate molecular entity a new name, without some
>evidence of biological meaningfulness.
>
>, or is there an actual
>> biological/evolutionary reason?
>
>I can't believe that there would be.  The existence of subspecies (if
>they really do exist) is completely dependent on the vagility of
>popuations and whether or not gene flow can occur.  Some
>butterfly species have been split to death, whereas others have not.
> Why?  Some species fly relatively long distances without a
>problem, whereas others are very sedentary.  The same would be
>true for different species of moths.  Moths have simply been less
>studied, and to some are less glamorous (thankfully!!), so the
>species have been split less.  And don't forget that the moths
>outnumber the butterflies by as much as 20 to 1.  We haven't
>finished naming the *species* of moths yet.  Given some time, we'll
>probably get around to splitting a bunch of the moths as well,
>whether they deserve it or not!
>
> 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"
>
>