standardized taxonomy (an old node on the thread that occurred while we were in the field)

Karstad-Schueler bckcdb at ISTAR.CA
Sat Sep 12 20:18:47 CDT 1998


JOSEPH E. LAFERRIERE wrote:
>
> I suggest picking up a copy of Linnaeus's Species Plantarum. There, you
> will find plants grouped into families and orders based not on
> phylogenetic considerations but rather simply on the number of
> stamens and pistils. Linnaeus, knew
> nothing of evolution nor phylogeny. He developed what to him seemed
> a perfectly rational, sensible, scientific system.

* but he knew that some of his groups were more 'natural' (which probably
meant 'supported by multiple characters') than others, and that some of
the flower-parts-count groups were among the least 'natural.'

> Over 100 years later, some other scientists proposed that
> we should use phylogeny rather than arithmetic as the basis for
> grouping species

* Or more precisely, that evolutionists could regard the more 'natural'
groups in the pre-evolutionary classification as descendents of a common
ancestor, so that they took over the Linnean structure, sub-posing their
own theories because they felt that their theories better explained the
classifications than previous numerological or mind-of-God theories had.
And it was partly because the characteristics of the most-natural taxa
suggested descent-with-whatever-modification that evolutionists had
arisen.

More recently, paraphyletic groups became the ugly ducklings that
parts-count or numerologically-forced groups were in the early 19th
century, and classification has been taken over by new criteria (strict
monophyly) of what the taxa should mean. Again, the groups regarded as
'most natural' had turned out to be strictly monophyletic, and this led
cladists to propose that all taxa be formed on this model.

> You say that accepting Liguliflorae would be "wrong."
> It is wrong because it violates the human-generated criteria which
> you have been taught by other humans.

* but those criteria for 'wrong' have undergone the same kind of
winnowing as ways of judging 'good' orbital mechanics underwent in the
Copernicus-Kepler-Newton-Einstein sequence in the 'easy' sciences.
There's a whole body of theory that underlies the criteria for a
maximally 'natural' group at any time or in the mind of any systematist.

fred schueler,
Curator
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         Eastern    Ontario    Biodiversity    Museum
                Grenville Co, Ontario, Canada
(RR#2 Oxford Station, K0G 1T0) (613)258-3107   bckcdb at istar.ca
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