Polly's research focuses on quantitative evolution, phylogeny, and paleoecology of vertebrates. Much of his work has been on the
phylogenetics and functional evolution of
mammals, especially
Carnivora and
Creodonta, on the correspondence between phenotypic and genetic differentiation, on the role of functional traits in structuring mammalian communities, and on the evolution of multivariate quantitative morphological traits. With lead author Jason Head and other co-authors, he helped describe the giant fossil snake
Titanoboa and the associated methods for estimating paleotemperature from the size of extinct reptiles. ==Education and organisational affilitations==