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FEDUCCIA IN AUK/BEAST OF GEVAUDAN
Courtesy Luis, yesterday I received and read Feduccia's
'Birds are dinosaurs: simple answer to a complex problem'
(_The Auk_ 119, 1187-1201). If someone writes a rebuttal,
I suggest they use the same title. It seems there's little point
in arguing against most of the article, as the author has
made it fairly clear what he will acknowledge/cite/comment
Overall though, it's quite hilarious and here's why: pp.
1187-1197 explain why dromaeosaurs cannot be, and are
not, ancestral to/sister-group to birds. Then, pp. 1198,
Feduccia says dromaeosaurs might be flightless birds. Oh. I
see. In other words: dromaeosaurs definitely definitely
definitely cannot be anything to do with birds at all but, by
the way, they might be birds. As many have noted by now,
the idea that some maniraptans might be birds but that,
nevertheless, birds are not part of Dinosauria is as
defensible as saying that humans are not primates.
-- Much discussion and a table show how theropod and bird
teeth are fundamentally different. Even if this is true, so
what? Evolution. One can easily marshall a huge list of
features showing how radically different humans are from
other great apes, thus humans cannot be apes.
-- Carpals: he states that _Archaeopteryx_ has four carpals
and that the semilunate is a single carpal, not a compound
element. Old argument. In addition to the semilunate,
_Archaeopteryx_ seems to have two carpals (and I was
actually looking at _Archaeopteryx_ yesterday in the NHM
collections).. well, this is the same as bird-like theropods
(though three carpals in addition to the semilunate have
been suggested for _Microraptor_). It still makes no sense
why Feduccia argues that the bird semilunate cannot be
homologous with that of other maniraptorans.
-- Hands. Fair enough, this is still controversial even though
the frame-shift hypothesis has proposed an answer. But
what seems philosophically difficult is Feduccia's position
that 'if one key synapomorphy were falsified, it would
reduce all the other synapomorphies to the status of
parallelism or homoplasy'. He cites Howgate (1985) for
this! I really don't understand the logic here. How do we
know when examing characters which proposed
synapomorphy is the 'one key'? And as we know, even
assuming that non-avian theropods and birds DO have
different digital formulae, birds still fall within Theropoda.
-- On 'dino-fuzz' he draws analogy with the internal skin
fibres described on ichthyosaurs by Lingham-Soliar. This is
seriously misleading for a host of reasons and in fact the
ichthyosaur fibres do not resemble those of the theropods in
Here is a critique of this notion from personal
RE: skin fibres/integument.
In the ichthyosaurs the fibres can be seen to either overlay
bone or clearly be _within_ (viz, medial to) the external
skin surface. Furthermore they look nothing like the
structures seen on the theropods: the only ones that _do_ are
arranged in an orthogonal meshwork and are preserved as
overlapping layers that, again, were clearly embedded
within the dermis. Structurally these fibre meshworks are
interpreted by Lingham-Soliar (the describer of these
structures) as analogues of the cross-fibre arrays seen in
sirenian, cetacean and shark skin. Because such cross-fibre
arrays appear to have evolved as a means of keeping the
skin strong, flexible and smooth there is no reason to expect
such fibre types in terrestrial vertebrates like dinosaurs and
indeed, similar structures are not seen in other vertebrates.
The fibres in the theropods are clearly _external_ to the skin
(even in _Sinosauropteryx_ where a layer of resin has been
misinterpreted as an epidermal impression by certain
workers), exhibit a definite tufted or branching morphology
and exhibit barbs in NGMC 91 and _Cryptovolans_. In
NGMC 91 the fibres extend for a substantial distance
beyond the skeleton and in this and the other fibre-bearing
theropods these structures appear morphologically
identifical to the fibres (i.e., not the remiges and rectrices)
of _Caudipteryx_. The simple parsimonious conclusion is
that these theropods therefore possessed integumentary
'fuzz' similar (superficially at least) to that of ratites.
-- He argues that dinosaurs have a fantastic fossil record and
that therefore the idea of Jurassic ghost lineages for
Cretaceous maniraptorans is implausible. He argues that
because hundreds of Jurassic coelophysoid skeletons are
known (p. 1197) then the absence of Jurassic proto-bird
dinosaurs is evidence of absence. Morrison Fm
maniraptorans are said to be nothing more than
'unidentifiable trash'. None of this gets round the fact that
Jurassic small theropods are very poorly represented due to
assorted sampling/palaeobiogeographical regions,
something he refuses to acknowledge. The absence of
evidence here (good evidence) is a weakness though: can
someone please go out this weekend and find a mid-Jurassic
lagerstatte full of small coelurosaurs please?
-- Feduccia seems not to be aware of any work done on non-
avian archosaur phylogenetics since the time of Romer, nor
on the distribution of characters. He indicates that
_Ornithosuchus_, _Postosuchus_, _Lagosuchus_ (ignorance
is bliss) and _Lagerpeton_ pose problems for dinosaur and
archosaur phylogeny, again without citation of any of the
stacks of work done on these forms; follows Chatterjee
(1985) in implying that _Postosuchus_ is strongly theropod-
like; and cites Welman (1985) on the alleged birdiness of
_Euparkeria_. It is academically dishonest to cite works like
these when there are substantial, more recent reappraisals..
or am I wrong in assuming that he is up to date with the
literature? Of Dinosauria, he even writes that there has been
'extreme difficulty in defining this important clade' (oh
really?) and writes that 'if the thecodonts can be termed a
'garbage bag assemblage', then why not the Dinosauria'.
This makes no sense whatsoever... exactly like saying 'If
Gaviomorphae [polyphyletic group including
hesperornithiforms, loons and grebes] is a garbage bag,
what about Passeriformes?'.
In the interests of free speech, Feduccia should of course
continue to say what he likes. But while this article and
others like it will never be cited by anyone excepting three
or four select authors, we must still consider that those who
are not specialists in this field might take his comments at
face value. A quote I half-remember from an article on the
spread of creationism in Turkey was "If intelligent people
keep quiet, it only helps those who spread nonsense".
And now to something seriously off topic but re:
_Brotherhood of the Wolf_, the take in this film is that the
Beast of Gevaudan was an African wolf-like carnivoran
kitted out with a suit of armour (!). It was not intended to be
living creodont (though, it has been suggested it in the
literature that it was a surviving _Machairodus_; however,
has also been suggested it was a hitherto unknown giant
giant mustelid or a werewolf).
Of course the real Beast of Gevaudan (which attacked
people throughout Gevaudan, France, between 1764 and
1767) is still something of an enigma - it is implicated from
the white marking on its chest and the fact that it wagged its
tail as it attacked people that it was a trained dog or
dog/wolf hybrid (this is Jean-Jacques Barloy's theory; IIRC
he is interviewed about this on the _Brotherhood of the
Wolf_ DVD). However, the skin of the animal killed by
Antoine Chastel (sent to kill the beast by Louis XV in 1765)
was recently rediscovered in the collections of the NMNH,
Paris, and is a striped hyaena (_Hyaena hyaena_). Because
attacks and sightings continued after 1765, this animal
cannot have been solely responsible though.
Jullien, F. 1998. La deuxieme mort de la bete du Gevaudan.
_Annales du Museum du Havre_ 59, 1-9.
I didn't think the dubbing was so good, plus all the fight
scenes were a bit daft.
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL
tel: 023 92846045