Kaleb Sellers

I am interested in understanding the biomechanics of complex structures such as the skull, particularly during evolutionary transitions. From its ancient origins, the vertebrate skull has evolved into an astounding diversity of forms in various lineages. I study crocodiles and their relatives in order to ask questions about the evolution of form and function.

Crocodylians are an excellent group in which to test evolutionary and biomechanical hypotheses. As crocodylians live in depositional environments like ponds, the group has an outstanding fossil record. This fossil record bears witness to the profound changes experienced by the skulls of crocodiles and relatives.

Modern crocodylians are flat-skulled (platyrostral) with a long rostrum (longirostrine). The crocodylian skull has also evolved a bony secondary palate, broad cranial sutures, and a novel craniomandibular articulation known as the pterygomandibular joint. However, ancestors of crocs had a conservative skull design more typical of archosaurs.

The radical changes seen in the crocodylian skull may represent adaptations to their extreme feeding performance. Extant crocodylians have the highest measured bite forces, and some fossil taxa have been calculated to bite harder than the largest predatory dinosaurs such as Tyrannosaurus. Modern crocodylians also process food by their characteristic “death roll” behavior.

I am currently working on using classical anatomical techniques and computational modeling to investigate the biomechanics of the feeding apparatus in the American alligator. By comparing my findings with in vivo data, I can provide support for my methods and confidently apply them to fossil taxa. Future work will focus on fossil relatives of crocodylians.