[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
SVPCVA 2000, part 2
Onto my patchy garbled recollections of SVPCA. Apologies if I have
misrepresented any talks (I did a particularly bad job with Adam's and
Max'). Yes there is an abstract volume. It was edited by Stig Walsh but
is officially anonymous, being one of those volumes only handed out
at conferences. I suppose copies can be obtained from us (the
organisers) but they will have to be photocopies I'm afraid.
In the last email there were a few dinosaur things I neglected to
mention. Phil Manning, in his talk about new Yorkshire coast
discoveries (mentioned further below), recounted the discovery of
previously unnoticed _Scelidosaurus_ material in the collections of a
Yorkshire museum (possibly Whitby). The material was collected in
the 19th century. What will interest Jim Kirkland (hint) is that the
material - a few caudal verts - had the scutes preserved in the GSP style
(i.e. scutes stick up vertically from dorsal surface: do not project
laterally). Please pass this onto Jim if you are in current
correspondence with him. On the subject of scelidosaurs, this is out....
Martill, D.M., Batten, D.J. and Loydell, D.K. 2000. A new specimen of
the thyreophoran dinosaur cf. _Scelidosaurus_ with soft tissue
preservation. _Palaeontology_ 43: 549-559.
Eric Buffetaut's new Triassic sauropod (mentioned in part 1 email) is
_Isanosaurus_, the new taxon just described in _Nature_. The new
theropod I spoke about is, sigh, the 'cat-like' coelurosaur covered in the
national press last year. As I have explained before the 'cat-like' thing
was a total misunderstanding by a journalist.
Ok, onto the goodies. This time I'll do pterosaurs and marine reptiles.
Dave Unwin: _Sharovipteryx_: what can it tell us about the origin of
_Sharovipteryx_ is more pterosaur-like than previously noticed: there
is a patagium between the femur and thorax and there are aktinofibril-
like rods in the patagia that are IDENTICAL in size, shape and form to
aktinofibrils of pterosaurs. The femur is longer than the tibia, there are
elongate caudal verts and there are 4 sacrals. The foot is pterosaur-like,
the neck is long. Lots of nice photos. In parsimony analysis,
_Sharovipteryx_ is a prolacetiform closest to _Macrocnemus_. Unwin
ran David Dilkes' archosauromorph data set and included pterosaurs:
they are prolacertiforms in a clade with _Protorosaurus_,
_Macrocnemus_ and _Tanystropheus_ (and _Tanytrachelos_ IIRC).
Unwin thus supports the idea that pterosaurs are prolacertiforms and
Dino Frey: Pterosaurs, flying machines and the first 'bottom deckers' in
A new Crato Fm azhdarchid - this is the same specimen that preserves
complete feet and has strongly curved unguals and a scaly food pad
(discussed at SVPCA in Edinburgh last year) - has proved strikingly
complete and well preserved. The whole of the wing and leg (from at
least one side) are there. It is STRANGE. Legs are very very long,
wings proportionally short. The scap-coracoid is constructed such that
the glenoid is very low down in position (no they do not have it the
wrong way up) and the wings would have been positioned very low on
the body. Dino explained at great length the difference between 'top
decker' and 'bottom decker' aircraft: 'bottom deckers' are difficult to
fly, more manoeuvrable but unstable. Azhdarchids (or at least this new
taxon) seem to have been able to hold the wing in a shallow V and thus
confer great stability during flight. The abstract is lengthy and there is a
lot of aerodynamic discussion that I will not recount here. This
morphology is unique for flying vertebrates.
Lorna Steel: Internal helical reinforcing of the pterosaur wing skeleton.
X-shaped cross-bracing inside pterosaur long bones is a method of
internal reinforcing. Cross-struts in long bones are remodelled during
Will have to be brief as I've run out of time.
Mark Evans: The cheek of it: the skull of the plesiosaur
New specimens and interpretations allowed Mark to update the skull
reconstructions he'd produced in 1997 and 1999. A new specimen is
large and chunky: bigger (about 1.5 times) than previous specimens.
Individual variation or a new species? New specimen includes cheek
region (previously unknown) plus parts of suspensorium, lower jaw,
frontals etc. _Muraenosaurus_ is no dainty slim-headed predator: its
skull is deep and quite robust with a prominent sagittal crest and a
peculiar 'broken nose' effect on the frontals (a rugose bump rostral to
the orbits, dorsal to nares). This is not an artefact (is present in other
specimens). Not mentioned in the talk was the fact that the external
nares are rostral to the internal nares (reverse of condition now well
known for plesiosaurs). Despite the large size of the new specimen, it
was less well grown that the other, smaller specimens! In many
respects _Muraenosaurus_ is identical to cryptoclidids.
Les Noe: _Pachycostasaurus dawni_, a Callovian pliosaur (Reptilia,
Sauropterygia): is the new genus a juvenile?
Les showed lots of slides of the skull and how he'd managed to
reconstruct it. It is not a juvenile of a named pliosaurid taxon.
Richard Forrest: Plesiosaur necks, service cores and statistics.
Inspired by Ken Carpenter's recent elasmosaurid phylogeny papers,
Richard took issue with some aspects of cladistics. Am a bit bored
with these kinds of debates so will say no more.
Phil Manning: New discoveries in the Yorkshire Jurassic.
Dig at Kettleness, near Whitby, has yielded new ichthyosaur species. I
was on this dig.. though I didn't actually do any digging. Also new
dinosaur tracks and possible scelidosaur material.
Makoto Manabe: A 23 m ichthyosaur from the Upper Triassic of
Yes, 23 m. That is not a typo. First reported by an archaeologist
looking for Amerindian burial sites and then reported to the Tyrrell, the
specimen has not been easy to excavate and some deforestation has
occurred. Skull is more than 5 m long with enormous supratemporal
fossae which are floored with bone, pierced by tiny foramina. Very
odd. There is a slight tailbend preserved but there are no wedge-shaped
centra. Is not _Shonisaurus_, not does it seem to be a shastasaur.
Gigantic ichthyosaurs thus evolved in the Carnian-Norian and appear
to have died out at the end of the Triassic (but there are Liassic giants,
not mentioned by Makoto). _Utatsusaurus_ is now known from
Canada, suggesting biogeographical link across Panthalassian Ocean.
Still have synapsids, parareptiles and lepidosauromorphs to go. Might
find time later on today. In view of my previous comment (about
theropods being the new rodents), recently found the following quote.
It was written by Robert Wilson, a prominent rodent worker, in a
tribute volume on rodents:
"I still remember my first meeting with Richard Swann Lull when I
came east to study Bridger rodents at the Yale Peabody Museum. I was
ushered into his august presence by Nelda Wright, and after the usual
exchange of pleasantries, Professor Lull volunteered that he only knew
two things about rodents, that they all looked alike, and that they never
changed! Dinosaurs and mice and the twin shall never meet I suppose,
but the meek, as now based on numbers of workers, seem about to
inherit the earth" - - - R.W. Wilson, 1989.
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
Burnaby Road email: firstname.lastname@example.org
Portsmouth UK tel: 01703 446718