[Taxacom] Mona Lisa Smile
Thomas G. Lammers
lammers at uwosh.edu
Thu Jul 27 09:41:24 CDT 2006
At 09:21 AM 7/27/2006, pierre deleporte wrote:
>Tom's specification below gives some partial clues for a real, constructive
>discussion: he seems to need a phylogenetic classification - but I must
>notice that he doesn't states why: the nature of the desired classification
>is rather explicit, but a clear statement of the context of relevance for
>such a phylogenetic classification is missing.
Any classification seeks to express "relationships." Items are classified
together because they relate to one another in some fashion: appearance,
function, use, origin, etc.
The question then is what relationship shall we examine among living
things? To my thinking, the relationship that results from descent from a
common ancestor is likely to yield the best classification. Things
that share a common ancestor more often than not will have the maximal
number of things in common. This is not always the case, and that is where
I differ from strict cladists. Depending on the environment a lineage
faces, it may diverge considerably from its sister group as it maximizes
survivorship and fecundity. I have no problem lopping off such discordant
elements and leaving behind a homogeneous if paraphyletic group. I have no
problem with groups like "fish" or "reptiles" -- they are useful.
Thomas G. Lammers, Ph.D.
Associate Professor and Curator of the Herbarium (OSH)
Department of Biology and Microbiology
University of Wisconsin Oshkosh
Oshkosh, Wisconsin 54901-8640 USA
e-mail: lammers at uwosh.edu
Plant systematics; classification, nomenclature, evolution, and
biogeography of the Campanulaceae s. lat.
"Today's mighty oak is yesterday's nut that stood his ground."
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