[Taxacom] ALL angiosperms in just one Subclass Magnoliidae???
kennethkinman at webtv.net
Thu Mar 17 10:02:06 CDT 2011
Thanks for the clarification, that Chase and Reveal, 2009, is
separate from APGIII per se. However, the Royal Botanical Gardens (Kew)
is promoting this as though it is a package deal. In their press
release ("Easy as APG3"), RPG Kew made a HORRIBLE statement near the
very top: "Flowering plants are less significant than scientists
thought: downgraded from a class to a subclass."
That kind of statement cannot go unchallenged, especially
downgrading their significance as well as their Linnaean rank. Further
down it indicates that Chase and Reveal took "age of groups" (a
Hennigian proposal) into consideration in demoting flowering plants to
It is very similar to demoting Aves (birds) from Class status
because they evolved from reptiles. Otherwise, Hennigianism maintains
that you have to raise a bunch of reptile groups as separate Classes.
Thus various taxa have to be either promoted or demoted to different
ranks to avoid paraphyly (such as a single Class Reptilia).
In the case of angiosperms, that group makes gymnosperms
paraphyletic, so if one is paraphylophobic, one feels the need to demote
angiosperms in rank or promote a bunch of gymosperm taxa in rank. It
makes a lot more to have a Class Gymnospermae giving rise to a Class
Angiospermae (or even both as equal Phyla/Divisions).
It has everything to do with paraphyly, even if the word paraphyly
is not explicitly used. It is certainly implied in phrases like "age of
groups is taken into consideration". And finally, a rebuttal to John's
argument. Paraphylophobia is real and being widely taught as if it is a
necessary part of modern taxonomy (which it isn't). I see no evidence
whatsoever that "monophylophobia" exists---where people would suppress
clades (strictly monophyletic taxa) in a way that paraphylophobics
suppress paraphyletic taxa.
Anyway, here is the RBG Kew press release if you want to read it.
I still can't believe they said that "Flowering plants are less
significant than scientists throught". Would they say that about birds
Paul (dipteryx) wrote:
It has nothing whatsoever to do with paraphyly,
but with assigning a rank to the taxonomic group that is informally
known as Angiosperms. Rank is relative, a matter of context. There is no
inherent reason why treating the Angiosperms as a subclass (with the
name Magnoliidae) would be either 'right' or 'wrong'. It is perfectly
silly (not to say highly arrogant) to make an ex cathedra statement like
"Magnoliidae are such-and-such a group"; a context must be specified for
it to make any sense (for instance: "according to Chase and Reveal the
Magnoliidae are the Angiosperms").
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