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Re: Essentialism and such (was a bunch of previous subject lines)



Water-land transition, as it currently stands, could
conceivably used by ID supporters as "proof", because
the fossil record is still bad enough to allow
speculation of "guided" evolution.

Doesn't look like it, though, with all the diversity that is accumulating around *Ichthyostega*, and with all the weirdness that accumulates the longer people look at *Ichthyostega*.


Returning to typology, Barsbold's "ornithization" adds
a nice twist to the issue. Initially it seems like
typology, but it can't be farther from that.

The way you describe it it sounds like orthogenesis... :-S

"Ornithization" is the best I have yet seen to explain
alvarezsaurids, Nomonia, Microraptor, Rahonavis,
Vorona, Mei, Caudipteryx, Yandangornis etc pp:

What's so weird about *Vorona*? It clearly belongs to Ornithothoraces.

I believe that the distinction between cladistics and
phenetics is not as clear-cut as it may seem: any
cladistic approach which has a too broad scope of
characters essentially *becomes* phenetics: Cracraft's
infamous 1982 "Phylogenetic relationships and
monophyly of loons, grebes, and hesperornithiform
birds" was methodologically cladistics, as clean as it
could get at that time - but what he *did* was present
a conclusion that could only be considered phenetics
because his choice of characters was too coarse and
thus he ended up with a cladistic comparison of
overall similarity.

I disagree.

You are right when you say his choice of characters was too coarse. You are clearly wrong when you say it had a too broad scope of characters. It had too few characters. Far too few -- and among those select few there happened to be too many that had been subject to convergence. There can never be too many characters in a cladistic analysis :-)