[Taxacom] Molecular data and synapomorphies

[John Grehan]

From: taxacom-bounces at mailman.nhm.ku.edu
[mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of J. Kirk
Fitzhugh
> Ah, but only if the requirement of total evidence could be so easily
dismissed!  It can't -- which should 
> come as no surprise, given that no philosophers of science have shown
how one could rationally do without it.  

But maybe we could rationally do without the philosophers of science
since they always seem to be playing catch up.

> The causal questions being asked of sequence data are no different
from those asked of any other 
> properties of organisms to which phylogenetic theories are being
applied.

Perhaps so, but whether the data are capable of answering the same
question is, for me, the critical problem. If sequence data only provide
measures of overall similarity (with or without parsimony) then it would
appear that it cannot address phylogeny in the same way as cladistic
morphological data.

John Grehan