polarized and unpolarized
taxacom at IBSS.DVO.RU
Wed Jan 9 17:00:01 CST 2002
It seems the theme 'polarized and unpolarized' to be exhausted, and the discussion to change its course (through 'polarized'/holophyletic). Nevertheless, some comments...
In reply to Gianluca Polgar's letter I sent my opinion to her address directly and I see now (after the reading the views of taxacomers) an inaccuracy in my letter to Gianluca. It was as follows (January 6, 2002): "Dear Gianluca, before to speak of polarized and unpolarized characters, one should distinguish terms 'character' and 'character states'. Only states may be polarized, i. e. designated as primitive or advanced. As for characters, they may be polarized, if states are successive, but if states are simultaneous (as in Mendelian inheritance), characters are unpolarized".
I'm glad that my opinion is in agreement with Curtis Clark's ("polarization refers to deciding which among a set of character states is acenstral and which are derived") and Herbert Jacobson's (if polarization = dividing into states, there is no unpolarized characters, and one of terms is superfluous; coding is also superfluous), but Ken Kinman's suggestion that "there is a difference between polarizing characters and polarizing character states" gave me a quite different idea (in comparison with the last sentence in my letter to Gianluca:
In fact, characters themselves (in all the diversity of their states) can be polarized too, but this 'polarization' is called a HIERARCHY of characters. Terminology here is not 'primitive' or 'advanced' but higher or lower (in level): one cannot say that higher characters are 'primitive' or 'ancestral' to lower characters, though they appeared earlier in evolution.
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