polarized and unpolarized
taxacom at IBSS.DVO.RU
Wed Jan 9 17:02:04 CST 2002
Some comments in connection with Pierre Deleporte' (very important) letter (January 7, 2002).
1. He wrote that one "can polarize characters (states) a priori... or a posteriori" and the latter process is a kind of ckecking of tentative polarization.
I never polarize states (it seems unnecessary for polarization of characters) but there is a deepest truth in the fact that a priori delineation of states needs a posteriori verification. This is even more true for the polarization (or ranking) of characters since taxonomists often change ranks after their hard work.
2. He wrote that different states are given a different weight, but, actually, states of the same character are of equal weight since 'weight' of a character means its position in a hierarchy. (If two genera differ in some character, and one genus possess a primitive state of this character, while another genus has an advanced state, one can trace a phylogenetic line but both states are equal in level, consequently in weight).
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