Adaptive radiation in the Triassic ichthyosaurs, its ecological and environmental background

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Work for the past two years has focused on the incredibly rich fossil faunas of marine reptiles in the Triassic rocks of northeastern British Columbia. This region has over 1200 meters of continuous Triassic marine sedimentation, spanning the Early, Middle and Late Triassic. The Triassic sediments in British Columbia contain a diverse assemblage of fossil fish, ichthyosaurs, thalattosaurs and sauropterygians, many of which are new to science. This study has involved the collection and preparation of new fossil material, and comparative study of critical collections in other institutions. The collection of a giant ichthyosaur specimen was completed. The excavation of the world's largest marine reptile was awarded the Rolex Award for Enterprise in 2000.All of the specimen was collected and is now undergoing preparation at the Royal Tyrrell Museum. Preparation completed to date includes the skull, both humeri, radii, ulnae, cervical and caudal vertebrae and pubis. Additional focus of this work was the depositional environment in an ecological context. Ammonites and bivalves from the locality are being studied by Paul Johnston (RTMP), conbdont analyses are being under taken by Mike Orchard (GSC- Vancouver), stratigraphy is being done by J-P. Zonneveld (GSC - Calgary), and palynological investigations were under taken by Dennis Braham (RTMP). Reese Barrick (North Carolina) took samples of both bone and surrounding matrix for geochemical isotope analysis.