different taxonomies, Re: Farewell to Species - reticulation

Thomas Schlemmermeyer termites at USP.BR
Wed Feb 16 11:30:50 CST 2000

Tom,now trying to answer this one sent a few days ago:

On (         Mon, 14 Feb 2000 10:35:41 -0500),         Thomas DiBenedetto
<TDibenedetto at DCCMC.ORG> wrote:

>If, by traditional, you mean pre-evolutionary, then I agree. Phylogenetic
>concerns in the field of taxonomy are still relatively new. For me though,
>that does not mean in any way that a non-phylogentic, a non-evolutionary
>taxonomy should be considered acceptable anymore. How much longer will it be
>until the evolutionary perspective is fully integrated into the conceptual
>architecture of biological thought?

Every problem has its own structure. The evolutionary perspective is only one
pilar in the building of biology. Pretty much of biology are simply problems
that come up and are consequently solved. I read, for example, that they now
engineer genetically a new type of bacteria, pertinent to the human mouth
flora, which transforms sugar into alcohol, instead of lactic acid, thereby
avoiding caries.

>The first goal [of taxonomy] mentioned (storage and retrieval of
>information) can be obtained already without available phylogeny. Or should
>one start to name species only when the complete phylogeny is known?
>Certainly, this would be nonsense.
 I think your last comment is a bit of a
>strawman. No phylogenetic taxonomist has ever felt restrained from naming
>species until the phylogeny is known. Naming a species entails simply
>recognizing it as distinct from all other species, and hypothesizing a
>higher level grouping ( a genus) of which it is a part. That hypothesis
>might change,,,so what?

OK, now you admitted it!  The hypothesis of a new species is a highly
sofisticated one which requires much expertise and knowledge. Yet, this
hypothesis is a purely typological one. At this stage of work, no phylogenetic
reasoning is necessary, it may be even of strong disadvantage (premature theory

>Thus, it is only logical that taxonomy itself cannot and should not be based
>on ancestor-descendant relationships already in the first take, rather
>ancestor-descendants relationships may be products that come out of good
>I dont see systematics or taxonomy having much of anything to do with
>ancestor-descendant relationships. "Alpha" taxonomy is about identifying
>distinct, previously unrecognized terminal taxa (new species), or
>revistiting previous proposals of that type.

OK, again you admitted that there are whole subdisciplines of biology which
proceed without evolutionary perspective.

>Ancestor-descendant relationships seem to me to be outside of the purview of
>empirical science.

If these relationships are outside the purview of empirical science, in which
drawer shall we put them?

>But to your more general point that taxonomy should not be based on
>systematics, but rather vice versa, I disagree. How could one discover
>anything about phylogeny through the use of non-phylogenetic taxonomy?

Why should we bother about phylogeny? Phylogeny in the traditional sense is the
search for rooted trees. Rooted trees however are not part of purely
descriptive taxonomy, as they require aditional knowledge from paleontology,
embryology and geology.
As I already tried to put clear, the morphological systematist who works,
usually, with the alfa-taxonomy of a small group may put up unrooted networks
at most. But it does not behoove to him to establish phylogenies, as, as you
yourself remarked, this would be outside empirical science.

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