Autapomorphy

[Cristiano Moreira]

On Wed, 15 Sep 2004 15:42:07 -0500, Vernie Sagun <sagun at UIUC.EDU> wrote:

>Dear Taxacomers,
>I would like to ask about the term "autapomorphy", as I
>understand this is a character state present in a taxon that
>is not present in other taxa and is therefore
>phylogenetically uniformative.

Actually, that character state can be present in other taxa as well, it can
even be synapomorphic for a different clade. So, this character may be very
informative in the cladogram, but not for the taxon in which it is
autapomorphic. Unless, of course this is a supraspecific taxon and you want
to extrapolate the observed character state to all species within it, as a
synapomorphy to that group.

Cheers,
Cristiano.