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I am most interested in how lineages and communities change over long-term time scales. My scientific work reflects my background in biology and geology, with a heavy emphasis on exploratory fieldwork. My research focuses on the rise of modern mammals since the end-Cretaceous extinction. I’m interested in understanding the mechanism that brought mammals from a small portion of terrestrial communities, to the dominant clade we see today.

Lineages

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I often use duplicidentates — rabbits, hares, pikas, and their ancestors — to understand how morphological systems such as teeth, skeletons, and skulls evolve in response to ecological or climatic influences. The basis of this work is comparative anatomy. Because duplicidentates have a well-resolved evolutionary history and a surprisingly good fossil record, they represent an excellent system to test macroevolutionary hypotheses within a phylogenetic framework. 

My research includes qualitative descriptions of Asian fossils that highlight the evolution of the dentition and hind limbs of these animals. This work illustrates patterns of mosaic evolution over scales of tens of millions of years, which resulted in highly transformed modes of locomotion and mastication in modern decendents. My quantative work investigates the origin of modern leporid morphology in the context of ecological and developmental constraints. I am using traditional and geometric morphometrics, incorporating mCT data, to capture the morphological gradient of living lagomorphs. 


Communities

I began fieldwork in Asia to try and understand the nature of mammalian faunal change across the Eocene ­– Oligocene Transition (EOT). That research was the first to tightly constrain the Eocene/Oligocene boundary within Asia, and helps to understand the nature and timing of mammalian turnover on a global scale. I am expanding this work into Tajikistan and western China to better understand the nature of the EOT more broadly, but also, to study other periods of dramatic biotic change in the Paleogene, and to see these biotic events may be coupled to continental-scale tectonism. To better understand the biotic mechanisms of faunal turnover, I work with colleagues to evaluate paleocommunity stability across periods of significant biotic change. We are modeling trophic structure of these paleocommunities to understand why some remain stable during periods of significant climatic perturbations, while others are strongly affected. 


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