Orangutan-human clade (brainstorming a little)

[John Grehan]

At 03:34 AM 4/9/2003 +0000, Ken Kinman wrote:
>John,
>     Thanks for posting that list of putative synapomorphies of the
> putative human-orangutan clade.  It was rather impressive at first, but I
> quickly became more skeptical.
>     These characters tend to cluster in areas like the shoulder, lower
> head (incl. teeth), and urogenital system.

If one chooses to be skeptical about characters because they are clustered
in a particular body 'area' then one is free to do so.

>Unfortunately, a single base mutation in a TBox gene can cause changes in
>these same disparate body regions (e.g., Pallister's
>Syndrome).  Therefore, the possibility that some mutation or two could
>likewise have caused convergence (homoplasy) between humans and orangutans
>must be raised.

One could invoke the same possibility for the other phylogenies.

>     I don't have the time to explore this possibility more deeply right
> now, but perhaps it is something you might want to consider.  I can only
> speculate whether this could be a rather complex "peanut butter sandwich"
> phenomenon, but I certainly wouldn't rule it out.

So could the other phylogenies.

Thanks for the feedback.

Dr. John Grehan
Director of Science and Collections
Buffalo Museum of Science
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