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TERRESTRIAL ARCHAEOPTERYX?



Having just picked up the new _Nature_ paper on _Eoalulavis_, I'm
interested in particular in the overview given on pp. 400-401 by
Dr. Kevin Padian. I'm concerned here with the debate over the life
habits of _Archaeopteryx_ (not again!), as here we find a refutation
of the arboreal theory which I'd otherwise thought to be well
supported.

We are all aware of Feduccia's conclusions on this issue (_Science_
259: 790- ->) - he found that _A_ shared marked claw curvature with
arboreal birds *only*, and that all terrestrial birds clustered
elsewhere on a graph. Elsewhere, he has stated that the ellipsoid wing
of _A_ is identical to that of extant woodland birds, and furthermore
_A_ totally lacks abrasion of the tail feathers - apparently always
observed in terrestrial birds with long tail feathers. His conclusion
is that _Archaeopteryx_ was 'fully a bird in the modern sense'.

Major objection to the notion of an arboreal _A_ is the absence of
trees from Solenhofen. Advocates of the arboreal _A_ say this is
reliance on negative evidence - furthermore there were apparently
numerous retrieved gingkos and other plants (many large) from
Solenhofen, all of which were destroyed in WW II.  I recall this being
debated on dino-l ages ago: can anyone support it from the literature?

Of course, we also experience problems with the *significance* of
_Archaeopteryx_ in littoral deposits - a large number of non-littoral
animals, including lions, komodo monitors, carrion crows and garter
snakes, turn up there in the modern environment. As ankylosaur fans
know, Coombs and others have reported on several nodosaurids found in
littoral deposits, but do we conclude from this that nodosaurs were
paddling in the Cretaceous shallows? With these complications in mind,
it is surely best _not_ to allocate _Archaeopteryx_ to a single
specific habitat and/or lifestyle: ornithologists have referred to it
as a good 'generalised' bird, in any case. Feduccia may be guilty of
this in that his vision of a purely arboreal _Archaeopteryx_ would
preclude notions of beach-combing in the animal..

But is this arboreal argument _really_ good? I know nothing of
statistics or anything, but I have been assured that sample size
etc. in Feduccia's claw curvature study is sufficient, and the case is
strong enough to provide a serious problem to those who want a
terrestrial _A_. Even John Ostrom has said that he believes Feduccia's
data to be on good grounds. So, I am interested to find Padian
writing: '...(_Archaeopteryx'_) claws are as similar to those of
ground birds as they are to those of climbing or perching birds, and
it has no obvious arboreal adaptations' (Nature 382: 401). He cites
the following paper as advancing this view: PETERS, D.S. & GORGNER,
E. 1992. _Sci. Ser. Nat. Hist.  Mus. Los Angeles Co._ 36: 29-37.

I'm not aware of this paper, and haven't seen it. Can someone please
tell me what it says? This is all beginning to sound like the Speakman
and Thompson conclusions....

"Guess it means the power's off"

"What do you mean _they_ turned the power off -  - they're animals man!"

DARREN NAISH