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SVPCA 50, REPORT III
Alas, parental and other duties have so restricted what time
I have available for research/email etc that I now face the
dreadful prospect of being literally _days_ out of date with
the latest news in dinosaur research. Some quick notes
before I get back to reporting SVPCA 50...
This just in..
Modesto, S. P., Damiani, R. J. & Sues, H.-D. 2002. A
reappraisal of _Coletta seca_, a basal procolophonoid
reptile from the Lower Triassic of South Africa.
_Palaeontology_ 45, 883-895.
Re: Oli Rauhut's new paper on the dinosaur teeth from Una
(Cuenca, Spain) in _Cret. Res._ 23.. Assuming that what is
in the final paper is similar to what was in review versions,
one significant thing in this paper not mentioned by Ben is
that Oli suggests that paronychodonts are
Re: SVPCA 50, last time I got as far as Fastnacht's talk on
dsungaripterids in the pterosaur section. This time round
let's see if I can get through dinosaurs...
Two talks focused on trackways. Jesper Milan looked at
undertrack preservation using live emus as trackmakers.
Anatomical details disappeared in transmitted tracks while
the track shape remained recognisable. Whether undertracks
ever form has recently been contested by Nadon.
Peter Griffiths talked about a fantastic trackway from
Crayssac where a small theropod (approx. hip height 47
cm), running at approx. 4 m/s, suddenly executed a dynamic
turn and then clearly ran back 180 degrees to its original
line of travel. Why it performed this abrupt about-turn is
unknown BUT it does so at the exact same point as another
dinosaur trackway is observed (thus implying avoidance
behaviour). At the turning point, the tracks show that the
animal rotated rapidly on one foot. As it did its tail swiped
along the ground, cutting into the sediment and leaving a
prominent trace. The turn was clearly abrupt, dynamic and
executed 'on a sixpence' thus, contra Carrier et al's recent
paper about inertia preventing long-tailed theropods from
being rapid turners, the trackway indicates that long-tailed
dinosaurs _could_ turn abruptly, and used their tails
dynamically as they did so.
GENERAL DINOSAUR STUFF
Michael Parrish discussed rib angulation and
scapulocoracoid position in dinosaurs. Ribs should be swept
backwards, obviously. Looking at sauropod ribs, Parrish
noted concave areas on the dorsal surfaces of sauropod
thoracic ribs that appear to correlate with scap-coracoid
position. Adjusting the pectoral girdle accordingly, he
found that the scap-coracoid was located a bit more
ventrally than normally recontructed, and consequently that
the sternal plates became somewhat 'flattened out' and lay
closer to the ventral surface of the thorax than normally
thought. The implications this has for dinosaurian
musculature were discussed.
Angela Milner showed that proteinaceous material
(specifically proteoglycans) could be detected in
_Iguanodon_ bones from Smokejack's Pit, Surrey. This is
the first report of proteoglycans from fossil bone.
Darren Naish discussed newly recognised material of
_Eotyrannus_ and its possible implications, a large
brachiosaurid cervical vertebra that shares some features
with _Sauroposeidon_, and the palaeopathologies seen in
the holotype of _Neovenator_ and the _Iguanodon_ found
with it. Both animals were bristling with injuries and the
_Neovenator_ preserves evidence of osteoarthritis: the first
report of this in Dinosauria excepting _Iguanodon
bernissartensis_ and chickens. Judging from the feedback I
got, this was technically the weakest and stylistically the
crappest SVPCA talk of them all. Still, you gotta laugh.
Colette Cherry spoke about bone histology in
_Thecodontosaurus_ and Anusuya Chinsamy reviewed
bone depositional rates among Dinosauria. Depositional
rates are significantly affected by environmental conditions
and, following experiments on quails, I _think_ Chinsamy's
point was that the short development time of extant birds
may cut down on the variation (development of LAGs etc)
seen in the bone development of other dinosaurs. She did
state that LAG development was not simply a
plesiomorphic thing (contra Padian et al.) seeing as
herrerasaurs apparently lack LAGs.
Adam Yates reviewed the prosauropods of the Lowenstein
Formation (better known as the Stubensandstein) of
Germany. Employing a specimen-based analysis of 34 (I
think) characters, _Sellosaurus gracilis_ was found to share
derived characters with _Plateosaurus_ and thus was sunk
into the latter genus. Meanwhile, _Efraasia_ was resurrected
from _Sellosaurus_ and lacks the derived characters of
_Plateosaurus_ (and in fact of the Plateosauria). It was
shown that _Teratosaurus minor_ has the same diagnostic
characters as _E. diagnosticus_, so _minor_ is the oldest
available name for the species. In Adam's phylogeny,
_Efraasia_ is a stem-sauropodomorph (as is
_Thecodontosaurus_ and _Satunalia_ I think [couldn't copy
down the whole cladogram fast enough]) while
_Riojasaurus_ + Plateosauria form a monophyletic
Prosauropoda that is sister to Sauropoda.
Kent Stevens talked about a specimen close to my
proverbial heart, an articulated, complete sauropod forelimb
from the Isle of Wight discovered by local collector Keith
Simmonds. Discovered adjacent to other vertically-mired
sauropod limbs (see my previous comments on these
specimens in the writeup for the Portsmouth SVPCA
meeting), this specimen definitely lacks a pollex claw and
carpals, has an ulnar olecranon and has tightly bundled
metacarpals in which mets I and IV (nearly touching at the
back of the hand) may have worked as a functional heel.
The big surprise is the identity Kent proposed for this form
(it wasn't a surprise to me as I'd had it discussed to me at
length prior to the talk, but anyway...): based mostly on the
proportions, he argued that it was a diplodocid, and more
specifically was closest to _Apatosaurus_. The glenoid was
1.8 m off the ground suggesting a total length of 9.8 m, so if
this is an apatosaur it's a dwarfed, thumbless form with
more columnar limbs than Jurassic diplodocids. However...
Paul Upchurch was not happy with this and, as you may
gather from the lack of a pollex ungual and ulnar olecranon
(and other characters), argued that a diplodocid ID was
unlikely and that the specimen seems instead to be a basal
Eric Buffetaut showed how new skull material of
_Phuwiangosaurus_ definitively links it with the
nemegtosaurids (e.g. _P. sirindhornae_ has the same caudal
quadrate fossa as does _Quaesitosaurus_, slit-like
supratemporal fossae etc) and is in agreement with a
titanosaur affinity for nemegtosaurids. Eric also showed that
_Huabeisaurus_ agrees with _Phuwiangosaurus_ in many
features and is probably a close relative. _Tangvayosaurus_
is also similar.
I initially thought Eric was talking about _Hudeisaurus_
(which resulted in a very confused conversation with
Sasidhorn Khansubha). The paper presenting these results
Buffetaut, E., Suteethorn, V., Le Loeff, J., Cuny, G., Tong,
H. & Khansubha, S. 2002. A review of the sauropod
dinosaurs of Thailand. In _The Symposium on Geology of
Thailand, 26-31 August 2002, Bangkok, Thailand_, pp. 95-
Jeff Wilson discussed trends of neck elongation among
sauropods. Early sauropod evolution is characterised by
duplication and incorporation events (i.e., eusauropods
incorporated a dorsal into a cervical and exhibit a
duplication of two cervicals relative to the ancestral
condition) but, excepting diplodocids (which incorporate
two more dorsals into cervicals), later sauropod clades are
not characterised by any neck-lengthening events. Instead,
individual genera seem specialised for their own neck
Theropods and ornithischians to come in next email...
Happy birthday to me.
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL
tel: 023 92846045