[Taxacom] Why Australians are more real than Americans: implications for taxonomy!

[Stephen Thorpe]

I don't wanna enter the debate either, but I will just say:

>First, don't fall into the trap of assuming that if species lack "real" boundaries, then we would see a perfect continum in nature right now.  While
this *is* true if you look at total biodiversity over its entire history on Earth; it is *not* a logical expectation at any given snap-shot in time

You are in the right ballpark, but playing the wrong game! 

>First, don't fall into the trap of assuming that if species lack "real" boundaries, then we would see a perfect continum in nature right now
It isn't a trap, it is a fact that if there were no "real" boundaries, then we would indeed see a perfect continuum in nature right now!

>While this *is* true if you look at total biodiversity over its entire history on Earth; it is *not* a logical expectation at any given snap-shot in time
It may well be true that there in fact aren't "real" boundaries if you look at total biodiversity over its entire history on Earth, but a lack of "real" boundaries over all time doesn't prevent there being "real" boundaries in any given snap-shot, including right now, but that is my point, not yours! THERE ARE 'REAL' BOUNDARIES RIGHT NOW, WHICH IS WHY WE DON'T SEE A CONTINUUM RIGHT NOW! This is independent of whether or not there are "real" boundaries over entire history ...

Taxonomists describe morphological diversity and the gaps between them. They don't specify or impose the gaps, they describe the gaps by looking at nature ...

Stephen


________________________________________
From: Richard Pyle [deepreef at bishopmuseum.org]
Sent: Monday, 7 September 2009 10:31 a.m.
To: Stephen Thorpe; TAXACOM at mailman.nhm.ku.edu; 'Jim Croft'
Subject: RE: Why Australians are more real than Americans: implications for taxonomy!

Seriously...I don't want to enter in this debate again.  My views on this
are well-documented in the Taxacom archives.

But I do feel compelled to clear a couple of things.

First, don't fall into the trap of assuming that if species lack "real"
boundaries, then we would see a perfect continum in nature right now.  While
this *is* true if you look at total biodiversity over its entire history on
Earth; it is *not* a logical expectation at any given snap-shot in time.

Second, as long as you conceed that the boundaries are fuzzy, then we are
really only arguing about the average degree of fuzziness across
biodiversity.  In your view, most species boundaries have a scale of fuzz on
par with the beaches of Australia.  In my view, the fuzziness of most
species boundaries is more on a scale such that Australia, Indonesia, and
New Guinea have overlapping (sometimes broadly overlapping) fuzz.

Third, humans are a bad example, both because of our sudden and dramatic
increase in dispersal potential in the past couple of centruries, and
because it's too close to home.

Aloha,
Rich


> -----Original Message-----
> From: Stephen Thorpe [mailto:s.thorpe at auckland.ac.nz]
> Sent: Sunday, September 06, 2009 11:53 AM
> To: Richard Pyle; TAXACOM at mailman.nhm.ku.edu; 'Jim Croft'
> Subject: RE: Why Australians are more real than Americans:
> implications for taxonomy!
>
> >So... if I understand you correctly... you're under the
> delusi...err....impression that "real" species boundaries
> exist in nature outside of human imagination and convenience
> -- correct?
>
> It is manifestly self-evidently so! To deny this is up there
> with Grehanian denial of the evidence that points to the
> human-chimp relationship!
> Importantly, though, I am NOT saying that species boundaries
> are ALWAYS absolutely precise and clear, and indeed, there
> isn't an absolutely precise boundary between Australia and
> ocean either - the tide goes in and out and it is a fuzzy
> boundary. Nevertheless, Australia does have "real" boundaries
> in nature outside of human imagination and convenience -- correct?
>
> To see the "real" species boundaries, you only have to
> imagine a world in which there were none. I hope you have the
> capacity for imagination! :) In such a world, every
> morphotype would grade imperceptibly into every other
> morphotype. Species boundaries would have to be imposed
> completely arbitrarily.
>
> I repeat a previous analogy: there are heavy people and there
> are light people, but it is not a very useful classification
> because of the continuum between them. But if all people of a
> certain intermediate weight class died out, then we could
> classify people usefully by weight. It would not be a
> taxonomic classification, but it could be! Imagine a world
> with two extant species of Homo, morphologically identical
> except that one species were 30-60kg, and the other species
> 70-120kg as adults...
>
> Stephen
>
> ________________________________________
> From: Richard Pyle [deepreef at bishopmuseum.org]
> Sent: Monday, 7 September 2009 9:36 a.m.
> To: Stephen Thorpe; TAXACOM at mailman.nhm.ku.edu; 'Jim Croft'
> Subject: RE: Why Australians are more real than Americans:
> implications for taxonomy!
>
> > Yes, Richard, species ARE real entities in the world! They
> might not
> > have existed in a world where there was an unbroken
> continuum between
> > diverse morphologies, but in our world there are "gaps" which break
> > the biotic realm up into species.
>
> Please... for the sake of us all... don't get me started. :-)
>
> So... if I understand you correctly... you're under the
> delusi...err....impression that "real" species boundaries
> exist in nature outside of human imagination and convenience
> -- correct?
>
> If so, we are operating under fundamentally different
> presumptions about the nature of biodiversity, so we will
> never arrive at a mutual understanding of what is meant by a
> "taxon concept circumscription"*.
>
> No sense cluttering the list again with this debate -- there
> are enough iterations of it in the Taxacom archives.
>
> Aloha,
> Rich
>
> *Note: My use of the elaborated term "taxon concept
> circumscription" is to disguish it from "species concept" (in
> the sense of "biological species concept", "phylogenetic
> species concept", etc.) -- which is an equally contentious
> and very-much related debate, but still quite different from
> the "species are real" debate.=