Palaeobiology of non-avian theropod dinosaurs

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This program represents my continued research on the palaeobiology of non-avian theropod dinosaurs, which are rare but diverse, and tend to be fragmentary. This makes it a challenge to understand the anatomy and interrelationships of an important and interesting group of animals that is represented today by birds. Anatomical and phylogenetic studies provide a foundation for studies of growth and variation, evolution, biomechanics, physiology, palaeoecology and behaviour. Most of my research is done on specimens from Alberta, but I also have long-term projects in Argentina and Asia that are directly relevant to the research program in Alberta. Dinosaur Provincial Park is my main focus in Canada, and is one of the richest dinosaur sites anywhere in terms of species diversity, numbers of skeletons excavated, and the variety of fossil types. The Dinosaur Park Formation arguably has the most diverse assemblage of dinosaurs and associated fauna and flora. More than 800 skeletons have been excavated there, and at least two additional specimens are collected each summer. The best specimen of a small theropod (Saurornitholestes) ever collected in Canada was found in 2014, and is presently being prepared for research. More than 250 dinosaur-dominated bonebeds have been identified in the Park, and there are literally millions of bones exposed at any one time in the badlands. Hundreds of species of non-dinosaurian animals and fossil plants add to one of the richest dinosaur-dominated palaeoecosystems known. An overall picture is emerging of ecologically specific dinosaur communities in which individual taxa are rapidly evolving. And whereas the number of new taxa being identified is exploding, analysis of diversity in monospecific bonebeds is providing constraints by defining the variability (ontogenetic, sexual, individual) within single populations. Evolutionary changes in all dinosaur lineages can also be tracked through a succession of at least five different dinosaur faunas along the Red Deer River. Understanding evolutionary change locally is complicated by the immigration of closely related forms from Asia. My prime focus in Asia will continue to be the Nemegt Formation of Mongolia, which is roughly contemporaneous with the Dinosaur Park Formation. Anatomical projects that I have underway include the description and phylogenetic analysis of dromaeosaurids, oviraptorosaurs and troodontids of North America and Asia, and the analysis of variability and speciation in ceratopsians of western North America. The discovery of feathered dinosaurs in China in 1996 gave me many opportunities to work on specimens intimately related to the origin of birds. This work is continuing with a new taxon of Chinese troodontid. An ornithomimid collected in Alberta in 2009 has the nicest feather impressions known from North America, and is being analyzed with SEM and geochemical techniques.