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Re: Some thoughts on AVES



> Fortunately, I don't have to.  We only have to classify the specimens we
> actually discover.  For this reason, abstract apomorphy-based definitions
> like the one I gave do not bother me overly much.

Again, not only are you relying on a lack of knowledge (which we all labor
to fill), but are setting up a system which inherently has limitations. 
One of these limitations is the fact that you can only work with fossil
taxa.  Yeah, the biases in the fossil record are great for this type of
character-based classification system, but it doesn't work for extant
organisms.  Evolution is still happening, and we'll need to deal with
speciation in the future.  But contemporaneous 
speciation won't happen with those gaps that are inseparable from the
fossil record; the overnight-character-acquisition system cannot apply
today.

> Not necessarily (see above).  And besides, any adaptation, if defined
> strictly enough, must indeed have been acquired overnight.

I don't know if that's true.  We'd need a complete genomic understanding
of every individual in the population that speciates, which we can't even
define, and then a complete understanding of the future heredity patterns
of those individuals.  That's not possible.

And aside from all the problems listed above, the system is _still_ more
arbitrary that phylogenetic taxonomy!

-Demetrios Vital