[Taxacom] ordinal splitting (vs. lumping)
kennethkinman at webtv.net
Tue Sep 20 22:03:06 CDT 2011
A paper in last week's issue of Proc. Natl. Acad. Sci., is very
interesting in that it further documents the mass extinction of higher
bird taxa at the very end of the Cretacous, especially in North America.
No big surprise, being geographically so close to the impact off
Yucatan. Most of the bird survivors (Archaeornithes or Neornithes) were
clearly (and luckily) in the southern hemisphere (Gondwanaland), while
it was just bad luck if you were in North America at the time.
However, the erection of a new Order Palintropiformes is totally
unwarranted, as it is preoccupied by the name Apsaraviformes Livezey and
Zusi 2007. Furthermore, it is most likely a subclade of the even
earlier (and more inclusive) Order Ambiortiformes (which is the name I
used in my bird classifications as sister group to Hesperornithiformes
and higher birds).
Granted, the ICZN does not mandate priority for the names of taxa
above family group, but this kind of extreme splitting (and ignoring
previous classifications) seems a clear result of the proposed PhyloCode
and authors positioning themselves to get PhyloCode recognition (at some
level). Never mind that it is likely with Palintropiformes ending up
(at best) as a subclade of an even larger ordinal grouping.
The galling thing is that splitters tend to get more press
coverage, and perhaps therefore get a better chance at future funding.
The squeaky wheel tends "to get the grease" (as in many other aspects of
human endeavor), and in taxonomy it seems like splitters (no matter how
extreme) often tend to get more "grease" (i.e., media attention and
But as was recently quoted here (from Asimov), there are always
exceptions. When it comes to angiosperm Orders, lumping in the last
dozen years has become the "in thing" to do, whether or not such extreme
lumping is always the best policy in the long run. In my experience,
bird Orders are too oversplit and angiosperm Orders (at least in APG)
are somewhat overlumped (an overreaction to traditional angiosperm
classifications, which were usually badly oversplit). One extreme often
generates an overreaction that tends to overshoot and generate an
opposite extreme (although thankfully only a few overreactions in the
case of angiosperm Orders). At least the pendulum swings for
angiosperms are now becoming less extreme (which seems to be some
measure of progress and stability).
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