"Species?"

[bill and Dale]

Hi all.  Before I begin this post I should say that my background is not
entomology but rather mycology (fungi) and my ideas about species
concepts come from that field.  However the discussion has been so good
and provocative I wanted to contribute.  Since the species thing has
gone on so extensively I thought I'd give my humble opinion-
    The only "real" species is the individual you are holding in your
hand that was extracted from a wild population.  The species concept is
an intellectual corral that we attempt to erect around wild populations
that share, 1. A common ancestor. 2. A common gene pool. 3. A high
degree of morphological (also chemical, molecular, etc.) similarity 4.
The ability to sexually reproduce with others within the corral.
Individuals that we extract and examine from within the corral we say
belong to  "that species."  Individuals that we examine that are outside
the corral we say belong to "another species". Individuals that are on
the fence somewhere we say are "subspecies". Those on the fence may
struggle off the fence and wind up outside the corral and then a
taxonomists comes along and says "hey this is a new species, I'm going
to describe it."  The individual on the fence may stubble and fall back
inside the corral and get reabsorbed into the wild population there:  It
does not become a new species or a subspecies. Sometimes a number of
individuals on the fence intact sexually only with each other and form a
sub specific population, whose weight eventually breaks the fence and
they become a new species. Sometimes the corral is so large
geographically or the area within the corral is so diverse that the
members within the coral look different.  This is a cline.  Sometimes
widely separated corralled populations are determined to be same in
terms of the description of the originally described population. They
are the same species. Sometimes an individual from outside the corral
jumps the fence and can interbreed with the individuals within the
corral. This individual may have a genetic trait that is adaptive and
that gene may spread through the population to the point where the whole
population changes into something that no longer resembles the other
populations that were once called the same species.
   The point of it all is that species, subspecies are constructs that
represent the opinion (hopefully based on good science and sound
research) of taxonomists about where to erect the conceptual fences that
will surround the individuals of a population of naturally occurring
sexually compatible individuals that the taxonomist wants to call by a
specific Latinized binomial (or trinomial). The fact that the
characteristics that serve as the model for this name are based on one
individual (the "Type") or a small series of individual sometimes leads
to a lot of confusion. If you think that the taxonomy of lepidoptera is
sticky take a stab at fungi! Forget about it!
       Anyway that's my small contribution to this discussion and I'm
sure some will disagree but that's all right with me.
                                                         Bill Yule


 
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