[Taxacom] Elimination of paraphyly: sensible or not?

[Richard Zander]

Paraphyly is not a process in nature. It models nothing real. It is a gimmick used by cladists because there is no innate taxon concept in cladistics.  It occurs when one taxon generates one or more other taxa of the same taxonomic level.



Phylogenetics is not the study of evolution. It is the study of dichotomous trees generated by non-ultrametric cluster analysis using character state changes. Cladistics is better at grouping evolutionarily related taxa than cluster analysis by overall similarity, but it does not model an evolutionary tree.



To study evolutionary trees you need to be aware of (have information about) radiation of descendants from progenitors. Trees restricted to sister groups do not allow hypotheses of serial evolution.



This discussion is about classification based on a particular kind of cluster analysis, not evolution. Classification should reflect what we know about evolution, not cluster analysis.



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Richard H. Zander

Missouri Botanical Garden – 4344 Shaw Blvd. – St. Louis – Missouri – 63110 – USA

richard.zander at mobot.org

Web sites: http://www.mobot.org/plantscience/bfna/bfnamenu.htm and http://www.mobot.org/plantscience/resbot/