Australopithecus and orangutans

[Jason at]

Dear John,

I will remain in the sideline of the Chimp-Orang dispute. However, your
remark regarding molecular synapomorphies is just not true. Molecular
synapomorphies are determined during alignment (if you do multiple
alignment) or as the analysis proceeds (optimization alignment).
Polarization of the characters does indeed take place a posteriori based on
your outgroup... and so it should be regardless of the nature of your
characters. Making a priori judgments on the polarization of characters is
"unusual".

Maybe your criticism regards the shot-gun approach of molecular data, in
which "good" characters and "bad" characters are used. Although this is
maybe true, the only problem is extra noise, and hence loss of resolution.
But I rather have this than cherry-picking/ selection of characters...
either molecular or morphological.

Nevertheless the remark by Jason is also incorrect since you can't
objectively compare molecular and morphological data: at least the
comparison of number of characters is not useful .

I think that this on-going discussion underlines the great difficulties
encountered in systematics. For if we can't yet agree on this small problem,
what hope do we have with other more obscure groups?

Cheers

Jason

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