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NEW EVENTS IN GONDWANA & UK



Just received a pile of extended abstracts from _Journal of African 
Earth Sciences_, apparently there was a special volume called 
'Gondwana 10: Event Stratigraphy of Gondwana_ - I don't have the full 
citation: does anyone? Several of these abstracts relate to 
dinosaurs and contemporary fauna. Here are the most interesting 
ones...

ARCUCCI, A.B. New information about dinosaur precursors from the 
Triassic Los Chanares Fauna, La Rioja, Argentina.

_Lewisuchus admixtus_ is a dinosauriform related to _Marasuchus_, and 
_Pseudolagosuchus_ may be a synonym of it. The asymmetrical pes 
previously referred to _L. admixtus_ 'can be identified as belonging 
to a much smaller proterochampsid'. (Time to redraw that little 
cartoon Pete:))

BAEZ, A.M. and MARSICANO, C.A. A heterodontosaurian ornithischian in 
the Upper Triassic of southern Patagonia?

Heterodontosaurs are referred to in this abstract as 
Heterodontosauria (=Heterodontosauridae sensu Weishampel and Witmer, 
1990). A weathered left posterior maxillary fragment with dentition 
was found in the Laguna Colorada Fm of the El Tranquilo Group (late 
Ladinian-early Carnian) of the Santa Cruz Province and exhibits 
derived characters of the _Heterodontosaurus_-_Lycorhinus_ clade. The 
material is closest to _Heterodontosaurus_ in having no cingulum or 
constriction separating crown from root, and in wear patterns.. 
'Thus, a relatively advanced heterodontosaurian, _Heterodontosaurus_ 
or a closely related taxon, is represented in the Upper Triassic of 
southern South America'. Cool!

DE KLERK, W.J., FORSTER, C.A., ROSS. C.F., SAMPSON, S.D. and 
CHINSAMY, A. A review of recent dinosaur and other vertebrate 
discoveries in the Early Cretaceous Kirkwood Formation in the Algoa 
Basin, Eastern Cape, South Africa.

Briefly describes a new ornithopod known from 6 individuals - 
apparently all juvs - appears to be a derived iguanodont - and a new 
small theropod, previously announced at SVP 1997 I think. This 
theropod is pretty complete, and it's suggested that it's a basal 
coelurosaur. Has anyone seen photos of this fossil? ALSO a 
camarasaurid and a diplodocid: 'Diplodocids were previously unknown 
from the Cretaceous of southern Africa'. 

FORSTER, C.A. The continental dance: dinosaur evolution on Gondwana. 

Amongst other things, Forster notes that, if Novas (1997) is right 
about abelisaurids and carcharodontosaurids being close relatives, 
then 'current biogeographic hypotheses involving these clades will be 
vastly altered'.

SAMPSON, S.D., WITMER, L.M., FORSTER. C.A. and KRAUSE, D.W. The 
evolution and biogeography of Gondwanan theropod dinosaurs: new 
information from the Late Cretaceous of Madagascar.

Mentions the (then undescribed) new skull of _Majungatholus_, and 
says why they call it _Majungatholus_ rather than _Majungasaurus_. 
Very importantly, Sampson et al. cite Hay et al's new model of 
Gondwanan fragmentation which suggests that there were 
Indo-Madagascan  - S. American links, via Antarctica, until late into 
the Upper Cretaceous. Expect to hear more of this in the near future.

WELMAN, J. _Euskelosaurus_ and the origin of dinosaurs.

Talks about the transformation from the primitive paired arrangement 
of median eustachian tubes as seen in basal archosauromorphs (but 
basal archosauriform taxa are cited - _Proterosuchus_ and 
_Erythrosuchus_) to the transformed crocodile-style median system 
seen in prosauropods and early theropods. _Euskelosaurus_ is said to 
exhibit an intermediate condition.

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Last Saturday saw the Dinosaur Society conference 'British Dinosaurs 
- Their Lifes and Times', held at the Lapworth Museum, University of 
Birmingham. There were a number of excellent presentations concerned 
with dinosaurs, obviously focusing on the British ones. Here are a 
few of them...

David Norman spoke about historical aspects of Owen's work on 
_Scelidosaurus_. Faced with a complete scelidosaur skeleton - a 
quadrupedal, fairly graviportal dinosaur - why did Owen not take the 
opportunity to point out to his colleagues that he was right in 
reconstructing the other dinosaurs in the same way? Norman addressed 
this very interesting and not previously remarked upon aspect of 
historical dinosaurology.

Dr. Norman also spoke about the morphology of _Probactrosaurus_ and 
how it appears to be a sister-taxon to hadrosauroids. Basal 
hadrosaurs, like _Probactosaurus_, are _Iguanodon_-like in the head, 
without a marked duckbill. In his abstract Dr. Norman also addressed 
the taxonomy of _Probactrosaurus_ - three species have now been 
proposed but not all are valid.

Angela Milner addressed current research on spinosauroids, and lots 
of new/undescribed material was shown, including possible spinosaur 
material from Patagonia and at least two new African taxa, one of
which is huge but very very gracile in the snout. A photo of one 
spinosaur skull, whereabouts unknown, depicted a beast whose head 
would perhaps have been 2.5 m long (as shown previously at SVP 1996). 
_Baryonyx_ is a member of this clade, of course, and _Irritator_ and 
_Angaturama_ are too. Shared features include the lower jaw profile, 
S-shaped premax-max tooth row, maxillary peg that fits into a 
premaxillary socket and some interesting palatal features that I 
don't want to scoop. 

David Martill spoke about _Neovenator_ and the new Isle of Wight 
theropod. Can't remember what he said as I wasn't paying too much 
attention. Steve Hutt also spoke about the new theropod, work on 
which will get underway when Steve finishes his _Neovenator_ thesis.

BTW, why on earth are there rumours that _Neovenator_ might have been
venomous? (current ish of _DinoNews_). I've handled the fossils many 
times and see no basis for this whatsoever.

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Last night (Wednesday 21st) saw the first episode of the BBC's epic 
series _The Life of Birds_, and as it dealt with bird ancestry and 
fossil history, it warrant a mention.

No discussion whatsoever of the theropod-bird thing, and 
unfortunately a _Chlamydosaurus_ was shown transforming into 
_Archaeopteryx_. It was strongly implied that flight arose ground up, 
and that feathers may have evolved as threat display devices, as in 
_Chlamydosaurus_. I do appreciate that the programme makers didn't 
want to go into the bird ancestry thing too much, so I see the 
problem.

The computer generated _Archaeopteryx_ was a bit lame.

Next stop after the late Jurassic was the mid Eocene Messel shales, 
where a few Messel taxa were mentioned or shown, and a fleshed out 
_Diatryma_ was illustrated as a computer animation. Attenborough's 
claim that the biggest Messel mammals were little fox-sized 
protohorses was not correct, as big hyaenodontid creodonts are known 
from the site. Mention was made of a gigantic bird of prey, with a 20 
ft + wingspan.. I was confused: was this a reference to the 
Argentinian teratorn _Argentavis_? It didn't seem to be, as it was 
mentioned in the same breath as the Messel fossils. Is there some 
gigantic Eocene falconiform I have missed? I hope not. Not 
_Messelastur_ surely?

The programme ended with the Land of Birds, New Zealand. The idea 
they were playing with was: what might the world be like had birds 
'won' instead of mammals? NZ provides the answer, and there was great 
footage of kiwis, takahes, wattlebirds etc. Then there were computer 
generated moa - OK I suppose, but they showed exactly the same moa in 
the forests, in the grasslands, and in the mountains, whereas in fact 
different moa species occupied these different environments, and 
these different moa looked, well... different. _Pachyornis_ and 
_Dinornis_, two of the most disparate body plans in dinornithidom, 
differ markedly. The book _The Life of Birds_ does mention 
_Harpagornis_, so I expected a scene where we got to see one of these 
mighty raptors tackle and kill its moa prey. Indeed such a scene was 
enacted, but instead of doing an animation of a real _Harpagornis_, 
they superimposed some sort of forest _Accipiter_ into it all. Looked 
OK, but you could tell that the bird was small.. by _H. moorei_ 
standards, that is. 

I'm off now, and will return some time in middle November. Needless 
to say, I'm going away to get married. Wish me luck.

DARREN NAISH
darren.naish@port.ac.uk