SICB Division of Phylogenetics and Comparative Biology (DPCB)

DPCB Researchers Database Entry

Patrick OConnor

Evolutionary Morphology and Paleontology
I am interested in the evolution of archosaurs (birds, crocodyliforms and dinosaurs) and integrate laboratory, museum and field studies in an attempt to address various topics related to the morphological evolution and diversification of different archosaurian clades. My laboratory and museum research utilizes an integrated-systems anatomy approach in extant birds and crocodylians, whereas my paleontology work focuses on the morphology, systematics and paleobiogeography of mid-late Mesozoic terrestrial vertebrate faunas from Gondwana--with the latter focused on Cretaceous-age birds, crocodyliforms, and dinosaurs from Tanzania and Madagascar.

Among other topics, I am currently investigating the evolution of notosuchian crocodyliforms, an amazing group of small-bodied, terrestrial crocodyliforms that exhibit a variety of craniodental specializations that can best be described as "mammal-like." Many members of this group exhibit a reduction in the total number of teeth per quadrant concomitant with marked regionalization (heterodonty) reminiscent of carnivorous mammals (see the image of Pakasuchus kapilimai from the middle Cretaceous of Tanzania illustrated above). I am involved with ongoing field research in Tanzania, Madagascar, Egypt, Zimbabwe and Antarctica.