Darwin (was: Phylogenetic evidence)

[Roberto Keller]

>If I take this literally, then you are arguing that there can exist a clade
>in which the objects have absolutely nothing in common ("...members do not
>share any character state in common...").  If that's the case, then the
>"clade" does not exist - it cannot be supported by any evidence and, in my
>mind, consists of two mutually exclusive classes of unknown affinity.

Can you provide an example of such a clade?

Dick
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Take any monophyletic group you want and the synapomorphies supporting the
group are what all the members of the monophyletic group share. As Pierre
said, you have to interpret the observations (characters) in the light of
the most congruent hierarchical pattern.

Roberto

Roberto A. Keller
Div. Invertebrate Zoology
American Museum of Natural History
New York, NY 10024
USA

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