Modern-day Aquatic Species Comparisons to Trabecular Development in the Early Tetrapod Ossinodus and its Significance to the Vertebrate Conquest of Land

Nearly 350 million years ago, early tetrapods made a critical transition from living in water to living on land. To better understand how early tetrapods may have spent their time on land during their lifetimes, I examined a growth series of femora from an early Australian tetrapod, Ossinodus. I then compared these to modern-day turtle specimens with the goal of relating Ossinodus to either more aquatic or more terrestrial species. Preliminarily results indicate that Ossinodus may have lived their lives between the two environments. More comparisons to modern-day species may further these results.