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Feduccia's work is not unscientific. His book
on the origins of birds is of cours,e not a standard scientific work. His
real objection to saying BAD things is that BAD things are based on the
assumption that certain traits are homologous. He has concluded thru non
cladistic means, by means of "expertise" that the proposed synapomorphies are
actaully homoplasius. Forget about feduccia attacking BAD ideas, he is at
base attacking using the phylogenetic system itself. He attacks cladistics
by saying that cladistics gives BAD, while his own studies (using cladistics and
other methods, but whith the overiding emphasis on other methods) have given us
the BAND. The arguement against fedduccia is often that the synapomorphies
yeild BAD. This of course is neither an arguement against the BAND nor is
it a response to the BAND. To do that you need to argue that the
supporting synapomorphies are in fact synapomorphies, or agrue that the
explantions given for homoplasy are wrong.
Having said that, the death blow
to Feduccia is the discovery of uneqivocal feathers on unequivocal
theropods. Feduccia cant argue that Caudipteryx is on HIS
proposed bird line, nor can he argue that Caudipteryx and the like are not
on THE bird line, (or some branch there off ofthese lines to qualify the
statement). Things like Caudipteryx dont need detailed cladistic analysis
to demonstrate that they are theropods and that they are somewhere on the bird
line or a branch off of it. They quite obviously are. Furthermore,
something like archaeopteryx was a problem, becuase it is so close to the bird
line that it is blurry as to whether or not it is a theropd dinosaur. But
caudipteryx seems to be more theropod like, but still obviously having to do
with bird evolution. The only way to support the BAND now is to say that
dinosaurs and birds share a commyn ancestor that is neither dinosaur nor bird,
and that the theropod line retains the primitive trait of posessing, amoung
other things, feathers, while sauropods lost it, and the ornithischians lost it
also. In other words (look, its actually written out!!) the shared
traits between theropods and birds are synplesieomorphies (which would have to
be lost in the stem ornithischian and also a different set of characters would
have to be lost in sauropodomorpha) I think it is not possible to argue
that feathers evolved twice. Anyway, regardless of congruence of the
semilunate carpal, or underwhat selective pressures feathers arose, or the
origin of flight for that matter, feathers CANT be congruent, and they cant be
shut off for a while (phylogentically) and then switched back on.....at least i
dotn think they can be!?
~R.
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