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ARCHAEOPTERYX PNEUMATICS & TEETH, etc



Hello all. A minor disconformity in the workload allows me to make a 
minor input. On _Dromaeosaurus_, Tom said that the pedal elements 
referred to this genus by Colbert and Russell have not been figured: 
they have, in Colbert and Russell 1969. Mickey M (I think) said that 
_Archaeopteryx_ teeth lack serrations. Some of you may recall Josh's 
comment ages back that he'd seen serrations figured on an 
_Archaeopteryx_ tooth but had since forgotten his source - well, the 
Guimarota _Archaeopteryx_ sp. teeth have microscopic serrations. I 
don't have Weigert (1995) or Zinke (1998) to hand but I do have the 
new Guimarota volume. Oliver Rauhut's chapter on the dinosaurs 
_mentions_ the serrations, but they are clearly figured in Wiechmann 
and Gloy's chapter on 'pterosaurs and urvogels'. The serrations are 
minute and only visible under SEM, but they are there (Wiechmann 
and Gloy 2000).

These chapters (which, like the whole book, are a must have) are...

Rauhut, O. W. M. 2000. The dinosaur fauna from the Guimarota 
mine, pp. 75-82. In: Martin, T. and Krebs, B. (eds) _Guimarota - A 
Jurassic Ecosystem_. Verlag Dr. Friedrich Pfeil, Munchen. ISBN 3-
931516-80-6. 

Wiechmann, M. F. and Gloy, U. 2000. Pterosaurs and urvogels from 
the Guimarota mine. In: Martin, T. and Krebs, B. (eds), pp. 83-86.

Like most good academic books these days, it is offensively expensive 
and unavailable to you unless you're on an obscene salary. Oliver's 
chapter includes discussion and figures of the Guimarota 
_Stokesosaurus_ ilium (to which the tyrannosauroid premax teeth 
described by Zinke (1998) may be referable), possible 
_Ceratosaurus_, compsognathid, troodontid, dromaeosaurine and 
velociraptorine teeth. Most, but not all, of these taxa were reported by 
Zinke - the possible _Ceratosaurus_ record predates Mateus' report of 
this genus from Lourinha.

To get back to _Archaeopteryx_, have just seen this...

Christiansen, P. and Bonde, N. 2000. Axial and appendicular 
pneumaticity in _Archaeopteryx_. _Proceedings of the Royal Society 
of London, Biological Sciences_ 267: 2501-2505.

Per told me about this paper last year but other than this I haven't 
heard anything about it - the cover features Luis Rey's climbing 
_Archaeopteryx_ restoration (I phoned Luis from the library as soon 
as I saw this). Examination of the London specimen reveals pneumatic 
fossae on the sides of the thoracic centra (which are reoriented from 
de Beer's interpretation) and a pneumatic fossa on the proximomedial 
surface of the pubis - thus clear evidence of pneumaticity in this 
specimen. Neognaths don't have pneumatic pubes like this but 
Christiansen and Bonde demonstrate that palaeognaths do (they have 
a foramen in the same location). This data refutes Britt et al's 
statement that the non-axial skeleton of _Archaeopteryx_ was non-
pneumaticised and, needless to say, also contradicts Ruben et al's 
(1997, 1999) contention that _Archaeopteryx_ had simple lungs and 
was apparently apneumatic. The discussion section of this paper is a 
refutation of the theropod physiology model invoked by Ruben et al.

Interestingly, Christiansen and Bonde do regard the Eichstatt 
specimen as a distinct taxon - it may possibly require its own genus 
they say. They cite Bonde (1996) [Continental Jurassic volume], Mayr 
1973, Stephan 1987 [a German book called _Urvogel_] and... 
Howgate as support for this (Mike will be pleased, he was about Nick 
Pharris' comments:)).

Among other new things...

von Euler, F. 2001. Selective extinction and rapid loss of evolutionary 
history in the bird fauna. _Proc. R. Soc. London B_ 268: 127-130.

As species are lost, so is our ability to reconstruct evolutionary 
history. Sounds obvious but this is the first empirical test of the theory 
(I think). The removal of taxa via anthropogenic effects has a direct 
effect on tree imbalance - this is substantial and will increase as more 
taxa are lost. 

Podos, J. 2001. Correlated evolution of morphology and vocal signal 
structure in Darwin's finches. _Nature_ 409: 185-188.

Bill shape is correlated with song evolution and thus with 
reproductive isolation. This is a continuation of Podos' work on the 
mechanics of passerine song - should be read in conjunction with 
Grant and Grant and Grant et al's studies on Galapagos finch 
phylogeny, ecology and speciation.

Finally, we'll all heard an awful lot about David Marjanovic's article 
in _Quarterly Journal of the Dinosaur Society_ (which is now peer-
reviewed), but there were other articles in there that may also be of 
interest to some...

Liston, J. 2000. _Archaeopteryx_ and evolution of feathered flight: 
the hidden story. _QJDS_  4 (1): 6-14.

Massive historical review of everything about flight origins and 
discovery of key taxa, with (I think) discussion of Jeff's theory about 
crypsis and the evolution of feathers.

Naish, D. 2000. 130 years of tree-climbing dinosaurs: 
_Archaeopteryx_, 'arbrosaurs' and the evolution of avian flight. 
_QJDS_ 4 (1): 20-23.

Unfortunately submitted before _Microraptor_ and recent SVP 
presentations by Alan Gishlick and Scott Hartmann, so it's pretty 
naive.

Tarsitano, S. F., Russell, A. P., Rodriguez, D. S. and Stegall, L. 2000. 
Aerodynamic evidence for the evolution of protofeathers and avian 
sister group relationships. _QJDS_ 4 (1): 24-25.

Wing-tunnel studies show how protofeather models aid flow in the 
boundary layer in water tunnel tests. Need to reread it but they seem 
to argue that theropods could not evolve flight because the ventrally 
projecting pubis would generate too much turbulence. That proves it 
then.

Also an intelligent review of Feduccia (1996) by Richard Maddra.

***USA: STOP LOW FREQUENCY ACOUSTIC SONAR***

"Has not the whole of history been a search for false monsters?"
    - - Chatwin.

DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
Burnaby Building
Burnaby Road                           email: darren.naish@port.ac.uk
Portsmouth UK                          tel (mobile): 0776 1372651     
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