[Taxacom] Paraphyletic species and paraphyletic higher taxa
lists at curtisclark.org
Tue Dec 14 22:08:52 CST 2010
On 12/14/2010 8:17 AM, Chris Thompson wrote:
> first on yours
> "With a clade, you can always say "show me your synapomorphies". A
> paraphyletic group is argument by authority."
> Not exactly as a paraphyletic group is merely clade A minus clade B. A
> polyphletic group is merely clade A minus clades B, C, etc. So, it is
> not argument by authority.
But where, exactly, do you draw the line? Because every paraphyletic
group precludes the existence of many others, that's where it's argument
by authority. Clades can be nested, and every synapomorphy can diagnose
a named clade, but one has to choose one paraphyletic group over others
with slightly larger or smaller excluded clades.
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