[Taxacom] Morphology vs Molecular

[Richard Zander]

In one way, molecular is indeed phenetic. There is no weighting for phyletic importance. Well, there is one case, codon bias, in which selection on a pool of messenger RNA emphasizes one synonymous codon over another (if I have this right), but all other weighting (I think) is purely part of the analysis, e.g. avoiding 3rd codon positions because they may be over-saturated with changes. Basically the Dirichlet priors are all 1 in Bayesian analysis. In some cases certain site positions are weighted differently but I'm not sure how this is part of pre-weighting for phyletic importance.

(Now ask me what phyletic importance is.)

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Richard H. Zander 
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-----Original Message-----
From: taxacom-bounces at mailman.nhm.ku.edu [mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of Jason Mate
Sent: Monday, August 17, 2009 7:09 PM
To: Taxacom
Subject: [Taxacom] Morphology vs Molecular

Your counterargument is to say that molecular data is phenetic (how you got here is anybody´s guess) and that
a unique and intimate knowledge of the characters (read, I have been doing this for years so trust me) trumps any
amount of contradictory data (information that it not of the right kind).