Chondrichthyans, what we today know as sharks and rays, have been around for hundreds of millions of years. During that time they have changed significantly. With such a long evolutionary history, studying this group allows scientists to investigate the changes they have undergone through time, particularly during significant biological events during that time. Body size is hard to use with chondrichtyans as they are cartilaginous fishes, however more complete fossils are known which makes collecting this data laborious but important.
Maastrichtian raptor dinosaurs
Chondrichthyan body size evolution
Fossil pond turtles (emydids) are known for at least the last 35 million years or so. I am working on understanding the evolution of this group through their fossils along with describing multiple new fossil species.
Fossil emydids - pond turtles
I'm describing a new raptor dinosaur (dromaeosaurid) from the end of the time of the dinosaurs in the southern United States.
With several colleagues I am investigating differences in the myology (musculature) or various carnivoran mammals. While the focus has currently been on felids (cats), it will extend out to others, particularly mustelids (ferrets and minks).
Carnivoran postcranial variability
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