I am a broadly-trained paleobiologist who reconstructs the evolution of vertebrate ecology through major Earth transitions in the context of changing environment and biota. My work combines aspects of biology, geology, anatomy, and physiology to better understand how dramatic environmental perturbations influenced the evolutionary history of organisms.

Lizard dental morphology

Living reptiles display a remarkable range of diets which is matched by a variety of tooth shapes. My research on dentigerous reptiles seeks to establish links between ecology and dental morphology. In particular, I investigate a broad suite of dentitions from all major branches of crocodylians and squamates to explore the relationships between diet, ontogeny, and phenotypic tooth complexity.


Already my work demonstrated a clear pattern, with carnivores having simple teeth and herbivores having much more complex dentitions. This relationship follows the patterns previously found in mammal teeth, despite dramatically different morphologies, suggesting that dental complexity may aid in the reconstruction of diet in extinct taxa.

Crocodylomorph ecology

Extinct crocodylomorphs have a remarkably complete fossil record from the past 230 million years, including the survival and recovery from two mass extinctions. This record allows for the investigation of the relationship between survivorship and ecological role through major Earth system perturbations. My research uses a combination of dental complexity and skull shape to reconstruct the ecology of these extinct organisms and examine how they changed in response to mass extinctions.

 © 2019 by Keegan Melstrom