[Taxacom] Integrative taxonomy

[Richard Pyle]

No -- I'm using "candidate" species to represent cases where we lack a
minimum threshold of confidence in our understanding of the biology of the
organisms in question to warrant recognition as a full species.  Which, as I
understand it, is how the authors of the article intended to define it. And,
so it seems, you do as well.
 
To even consider recognition as a "candidate species", we have to assume
there is some minimal level of "consistent morphological [or genotypical]
differences".  When these differences are "too small to indicate
reproductive isolation" with sufficient confidence to justify a full-species
name, then a candidate species may be warranted.  In my mind, this is
exactly the sort of situation when we ought to consider subspecies
designators.  
 
Like you, I believe that we are always open to learn more about the biology
of organisms.  That includes an understanding of the extent of reproductive
isolation.
 
Rich


  _____  

From: Stephen Thorpe [mailto:stephen_thorpe at yahoo.co.nz] 
Sent: Saturday, July 31, 2010 6:26 PM
To: Richard Pyle; Aurélien Miralles; taxacom at mailman.nhm.ku.edu
Subject: Re: [Taxacom] Integrative taxonomy


>So....it seems to me that we are basically in agreement on this point; as
populations with consistent morphological differences that are deemed to be
too small to indicate reproductive isolation (given available information)
are prime fodder for "candidate" species
 
No, alas, I fear that our time of agreement is as fleeting as a marriage
between celebrities! The quote above sounds to me like you are now using the
term "candidate" species to mean populations that are on the evolutionary
road to full species, but haven't got there yet. This is not AT ALL how I
was understanding the term! Surely we were talking about cases where the
evidence for full speciation IN THE PRESENT is incomplete??
 
Entomologists and arachnologists (some mites) have had to deal for centuries
with organisms that have distinct life-stage morphotypes. Very few beetles,
for example, ever get described as new species from larvae. This doesn't
seem to be a problem. With some mites, there are names for larvae as well as
adults, and a big part of the taxonomy of these groups is to eventually
synonymize those names appropriately by association of life stages. Again,
it isn't a big deal. I just don't see how inventing a new class of names
(Candidati) helps???
 
Stephen



  _____  

From: Richard Pyle <deepreef at bishopmuseum.org>
To: Stephen Thorpe <stephen_thorpe at yahoo.co.nz>; Aurélien Miralles
<miralles.skink at gmail.com>; taxacom at mailman.nhm.ku.edu
Sent: Sun, 1 August, 2010 3:47:51 PM
Subject: RE: [Taxacom] Integrative taxonomy

> If, in a taxonomist's opinion, certain characters of certain specimens are
taxonomically significant 
> (in a non-continuum sort of way), then that taxonomist has every right
(and perhaps the duty) to 
> describe a new species on that basis. 

I agree completely.

> Informal tag names are a whole different can of worms. 

Indeed.

> They arise from the combination of two factors:
> (1) the need sometimes to refer to undescribed taxa 
> (e.g., in conservation management); and
> (2) the fact that formally describing species is becoming 
> an increasingly long-winded, expensive, and complex business, 
> if what you want to do is impress potential employers with 
> your "taxonomic sophistication", and/or taxonomic journals 
> want to compete in the "quality stakes" with each other.

The people I know of who routinely need to deal with "morphospecies" fall
into the former category, for the most part.  Except, it usually has little
or nothing to do with conservation management, and more to do with large
numbers of morphotypes, for groups that tend to have more than one life
stage, and whose biology is not well understood.  It's usually the case that
insufficient information and/or expertise is available to make a confident
judgement as to whether a new species-level name is needed.

> I think subspecies should only ever be used for allopatric 
> populations with consistent morphological differences that 
> are however too small to indicate reproductive isolation

So....it seems to me that we are basically in agreement on this point; as
populations with consistent morphological differences that are deemed to be
too small to indicate reproductive isolation (given available information)
are prime fodder for "candidate" species.

Aloha,
Rich