[Taxacom] Aversion to Paraphyly

[Fred Schueler]

On 9/8/2013 1:09 PM, Ken Kinman wrote:

 > You said: "birds are reptiles, get over it"?  But for over a century 
after Archaeopteryx was discovered, biologists were perfectly correct in 
alternatively saying that "birds are reptile descendants".

* Reptiles are a grade, not a clade, or maybe somebody can explain what 
monophyletic group "Reptilia" can represent that's different from "Amniota"?

 > If we have an aversion, it is simply an aversion to being preached to 
(for decades now) the erroneous notion that paraphyly is bad simply 
because phylogenetics says that it is.  And the strict cladists continue 
to rub it in with dumb jokes like "I bought a dinosaur to cook for 
Thanksgiving".  To me that just illustrates how elitist and silly it is 
to insist that "birds ARE dinosaurs", rather than "birds are dinosaur 
descendants".

* well, there's nothing wrong with including all descendents in the 
vernacular usage of a monophyletic group. It's a good lesson in 
evolutionary relationships to say that one is an Ape, Monkey, Primate, 
Mammal, Amniote, Tetrapod, Fish, and so forth.

The curious thing about paraphyly is that, unless the ranks of taxa are 
described by some sort of genetic, morphological, or temporal metric, 
it's *purely* an artifact of the use of categories in classifications. 
Just to take the easiest of these to implement, if, instead of "Family 
Proteidae" we said "Jurassic Proteidae" we'd preserve the hierarchy 
without commenting on "what category is appropriate in the mind of 
somebody." There could be squabbling about the date of divergence of 
groups, and there'd be guessing about poorly dated groups, but there'd 
necessarily be a monotonic sequence, and at least it would have an 
empirical basis, as opposed to squabbles about lumped/split categories.

 > If Richard's book helps a new generation of biologists realize how 
limiting and destabilizing strict cladism truly is, that would be great.

* and maybe another discussion of it on TAXACOM after we've read it.

fred.
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