Mayr on "What is a Species"
Mon Apr 26 14:51:41 CDT 2004
----- Original Message -----
From: pierre deleporte
To: TAXACOM at LISTSERV.NHM.KU.EDU
Sent: Monday, April 26, 2004 1:33 PM
Subject: Re: Mayr on "What is a Species"
At 15:46 23/04/2004 -1000, Richard Pyle wrote:
>1) Pierre Deleporte [...] I'm still not sure I understand why he seems to
>regard a "population" as something fundamentally more individual-like than
>a "subspecies" or "species"; but I suspect it will ultimately prove to be
>an issue of semantics, like so many others in this thread).
It's both an ontological and semantic issue.
If you think of a population including dead individuals, then there is no
difference with a subspecies or a species in this respect: one means in
fact the class of individuals, dead or alive, sharing some property (e.g.
being, or having being, part of the spatially and reproductively defined
and evolving system we call "this population"). However clearly delimited
or loosely delimited this "same population" can be in any of its successive
states, the fact is that dead plus alive individuals can't constitute a
"concrete cohesive whole".
Now if you consider only living members of a "same population", along a
wide spectrum of possible situations (of spatial closeness, of internal
biological connectedness...), you have something you can consider as a
biological system of some kind. I think I never used "individual" for a
population, but rather "biological system".
>2) I'm not sure I fully understand Ron's insistence that the notion of
>"subspecies" holds some special meaning to be distinguished from "species";
>except that "subspecies" just happens to be the smallest class of
>individuals addressed by the ICZN Code of Nomenclature.
Ron: Without life we have no biology - only taxonomy. To talk of "real
species" = objectively observable and natural, we have to be talking about
living organisms - don't we? As Pierre states, the dead organisms are
permanently and statically disconnected from the present living individuals
and individual population - even if they just dies 10 seconds or 10 million
Now about the ZN Code. The Code did not come first, biologists and
naturalists did. The "Code" evolved into terminological being as a
expression of the _reality_ THEY observed in nature. The first "species"
concept was simply local (regional) populations. Today, we know many many
of these are what we today call "subspecies". I brought up the ZN Code
because the glossary _writers_ point out the subtle but very important
distinction between a zoological taxon and a taxonomic taxon. I posted to
another group some months ago and mentioned the term zoological taxon to
which a high profile butterfly taxonomist responded and accused me of "now
making up terms". I pointed out this in the glossary and was amazed that
ANY practicing zoological taxonomist would not be familiar with these terms
and the great profound differences they address.
That Code addresses taxonomy - not biology. The vast majority of
hierarchal taxonomy is based on dead (non functioning) specimens = taxonomic
taxa. All subjectively determined by us. Taxonomic "species" are not
real (nor are taxonomic subspecies) because they are totally the constructs
of taxonomists' definitions (see page 119 of 1999 ZN Code). Zoological
taxa are real as they are "A [singular] _NATURAL_ [real] taxon of animals
(which may, or may not, have had a name applied to it."
Phylogenetic trees are also (by what ever Code) likewise, taxonomic taxa
being totally subjective to human placement based on the means, methods, and
opinions of systematists.
If we are really talking about real, then we are talking about that which is
biologically alive and present. That is epitomized by the single living
specimen. After that, the local (regional) unique and sexually
reproductively stable population of which said individual is a living
segment ("cell") of. These are basically referred to by us as subspecies,
varieties or strains. If they connect _taxonomically_ into "species"
(including circular, super, genetic, etc.) on a historical and global
platform, they become more and more subjective (un-real human) constructs.
The Codes were created to get all workers in a discipline using the same
terminological definitions. Thus, taxonomic taxon vs. zoological taxon.
Our terms not mine, and relavent terms to this discussion. Actually, the
answer to this discussion. Only a zoological taxon can be real - a living
nautral and observable biological entity. In my view, only one thing meets
that definition - a local population. A zoological subspecies sensu
stricto vs a taxonomic species. Thus, how was the question "Are species
real?" originally framed in the mind of the asker? As taxonomic and
systematic entities? Then no, they are not. As biological living
entities? Then only as naturally occurring unique regional segregates -
"subspecies". And if not that, than just the bird in the hand.
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