Avedinosauria (was: Understanding evolution problems)
kinman2 at YAHOO.COM
Mon Mar 8 22:08:31 CST 2004
Well, I for one am not hoping for anyone (young turks or even "older" turks, right or wrong) to "burn in hell". Strict cladists aren't really bad guys (ever notice that most are male?), but I just wish they weren't so aggressive and zealously self-righteous about rooting out and destroying every last paraphyletic taxon---not to mention a small minority of which have covertly (or occasionally even overtly) threatened eclectists in various ways (with the loss of job opportunities, funding opportunities, publishing opportunities, etc.). Strict cladists are widely distrusted and disliked for these and other reasons (although it's very encouraging to see that the "younger turk" Phylocodists are actually scaring the hell out of some of the older strict cladists).
Although I have been able to avoid much of that "drama" (having given up biology as an income-producing profession), what really bugs the hell out of me is that strict cladists often erroneously pass off paraphyletic groups as clades (when they are supposedly the ones "protecting" us from such "horrible", "unnatural" groupings). Have you ever seen discussions and cladograms showing Crustacea as sister group to either Hexapoda or Insecta? They probably do form a clade (Pancrustacea), but it is absurd to view them as sister taxa. Crustacea is clearly paraphyletic, so why pretend it isn't just to maintain a zealously pure taxonomy that is paraphyly free. I see this sort of thing quite often, and it is rather hypocritical (whether it is done intentionally or in careless ignorance). There is certainly no good excuse for it either way.
But I am certainly thankful that clear-thinking arthropodologists created a new name (Pancrustacea) for this wider grouping----thus avoiding the mistake made when Dinosauria was simply expanded (by strict cladists) to include birds (see postscript). Thus Crustacea is basically unchanged, and we don't end up with taxa with another dumb-sounding phrase like "non-insectan crustaceans".
The main reason the Three Domains are attractive to strict cladists is that a Kingdom Monera (Prokaryota if you prefer) is clearly paraphyletic. Sad thing is that both prokaryotic Domains are probably paraphyletic (I certainly have no doubts that Eubacteria are, even if you ignore the eukaryotic organelles). And the reluctance by APG to recognize an Order Rafflesiales is probably based in part on a nagging fear that it will make some other angiosperm Order paraphyletic. As I have stated, this will seem a little absurd when some of APG's megaOrders (like Malpighiales and Ericales sensu lato) turn out to be paraphyletic or even polyphyetic. In an effort to avoid small "problems", they end up making even bigger mistakes.
--------- Ken Kinman
P.S. If one needs a name for the clade (Dinosauria + Aves), I proposed the name Avedinosauria a few years ago on the DML (Dinosaur Mailing List). I considered (and even mentioned another possible name, Pandinosauria), but I think Avedinosauria is preferable. Thus the terms Dinosauria (and dinosaurs) can return to their former paraphlyletic meaning (= "non-avian dinosaurs"). Here's a link to that proposal:
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