How did vertebrates evolve? When did vertebrate traits such as paired fins and jaws arise? How do the earliest fossil vertebrates compare with living jawless and jawed vertebrates? To answer these questions, I study fossil armoured jawless fishes that lived 350 - 500 million years ago. 

What were the earliest vertebrate skeletons made of? How did they grow? How did vertebrate skeletal cell and tissue types evolve? I use CT scanning and electron microscopy to study ancient and modern vertebrate skeletons. I characterise vertebrate skeletal diversity and reconstruct the evolutionary history of skeletal traits. 

How are different animal groups related to each other? When did these groups diverge from each another? How can we estimate accurate relationships? I use anatomical trait data and DNA to estimate evolutionary trees. I evaluate different methods for estimating trees using sophisticated computer simulations.  

How do anatomical traits evolve? What is the best model of trait evolution? How do evolutionary rates, diversification and extinction change through time? I develop computational methods using R programming to address these questions.