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Re: Non-serpentine lacertids (was RE:WHAT'S GOING ON?)
In a message dated 7/3/00 1:00:37 PM EST, firstname.lastname@example.org writes:
<< It is never natural to remove a descendent from a supraspecific taxon. >>
I'd like to see a good reason for this opinion. It lies at the heart of the
differences between cladistic taxonomies and non-cladistic taxonomies and the
disputes between their respective adherent taxonomists. To me, a "natural"
group must include its common ancestor but need not include all the
descendant subgroups of this common ancestor (though it usually does). The
criteria for removing such a subgroup into an independent taxon are
qualitatively no different from the criteria that distinguish one species
from another. There is no difference in phyletic information content between
the statements "birds are dinosaurs" and "birds descended from dinosaurs."
Why should one be preferred and the other rejected?