Hi folks,



I hope to learn something, so that I can understand



phylogenetic analysis usually are based on molecular data, such as mtDNA (e.g. cyt b gene). On the other hand, Wiens (2000a) describes the use of morphological data in phylogentic analysis mentioning different "ideologies" of character selection and character exclusion from the analysis.

Some taxonomists seem to exclude even any character that shows (even slightly) infraspecific variation, others code them as "?" (=unknown or variable) and even other taxonomists use them all. Wiens seems to support the use of characters showing infraspecific variation, too, but how reliable are the trees when using morphological characters showing infraspecific variation. I guess the phylogeny becomes even more tendable, right?



How would you (professional) guys i) select and ii) code morphological characters? What about the use of quantitative and qualitative characters? When it comes to body scales, are there rules for subdividing the characters (e.g. in Kluge 1993)



Character: Ventrals

240-252 ; coding 0

258-265 ; coding 1

270-275 ; coding 2 and so on...



I recognized a gap between the numbers of scales for the states.



Cheers,

Wulf



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References:



Wiens, J.J. 2000a, In Phylogenetic analysis of morphological data, Smithonian Institution Press, Washington D.C.
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