[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Dinosaur gastralia and their function in respiration



  Communicated to usergroup by D. Tanke for new Tyrrell student Leon Claessens.

 For my current research on gastralia and their respiratory function in
dinosaurs, undertaken at the Royal Tyrrell Museum of Palaeontology, Alberta,
Canada, I would like to request information from anyone interested.

 The (preliminary) findings are the following:

 Gastralia are present in theropods, in prosauropods and in primitive
ornithischians. As relatively fragile, floating bone structures, they are
only recovered under relatively good fossilization conditions. In
tyrannosaurids they consist of two large medial pieces, connecting in the
mid-ventral line, and two small, sometimes fused lateral splints. All
tyrannosaurid gastralia interconnect in a zig-zag pattern. The bone exhibit
pronounced ridges and rugosities for muscle attachment, as well as
distinctive mid-ventral joints. Contraction of the belly wall musculature
makes the gastralia-system move as a ventrally situated rib analogue, and
therefore implies an important function in respiration.
 Although not necessarily always connected in a zig-zag pattern, the
gastralia in theropods most likely all consisted of two medial and two
lateral elements per segment. The description of Antrodemus (Allosaurus)
gastralia by Gilmore (1920) is incorrect and based on pathologic bone.
Therefore, at least in theropods, I suspect a uniform respiratory function
of the gastralia-system.

 The research on gastralia will approximately be fisnished in April/May,
1996. A few months later, after doing some (unrelated) fieldwork, I will
return to Utrecht University in the Netherlands. The research is funded by
the Canadian Government Graduate Student Research Award and by a grant from
the Molengraaff Fund.

 My questions are the following:
 -I would appreciate any information on gastralia present in the collections
of any institution. Furthermore, any information on articles that refer to
gastralia, as well as in dinosaurs and extant reptiles, is greatly welcomed
as an extension to my present listing.
 -At the moment I am particularly interested in the fact if there has ever
been any work done on the bone histology of gastralia (even though exo- or
endothermic ontogenetic origin histological differences generally do not
exist in adult vertebrates), and any (modern) articles on the function of
gastralia in extant reptiles (if any in existance).

 Any answers or questions can be posted at Darren Tankes' e-mail at (
dtanke@dns.magtech.ab.ca ) who has kindly allowed usage of his e-mail
number, or I can be reached by phone in the evenings or weekends at (403)
823-8941. My mailing address is:
 
 Leon Claessens
 Royal Tyrrell Museum of Palaeontology
 Box 7500
 Drumheller, AB, Canada
 T0J 0Y0

 Kind Regards, Leon Claessens.   
 Darren Tanke, Technician I, Dinosaur Research Program, Royal Tyrrell Museum
of Palaeontology, Box 7500, Drumheller, AB, Canada T0J 0Y0. (403) 823-7707;
(403) 823-7131 (fax); e-mail= dtanke@dns.magtech.ab.ca
 Paleo Interests: fossil identification and preparation, ceratopsians, Upper
Cretaceous vertebrate faunas of North America and East Asia, paleopathology;
senior editor on annotated bibliography  of extinct/extant vertebrate dental
pathology, osteopathy and related topics (2,000+ pages as of Dec. 1995).