The next UCD School of Earth Sciences online seminar will be presented by Dr Robert Brocklehurst (Harvard University) on 'The present as the (skeleton) key to the past: How functional anatomy of modern vertebrates illuminates major deep-time evolutionary transitions'.
The vast majority of species which have ever existed on Earth are now extinct, leaving behind a rich fossil record documenting what has gone before and how modern biodiversity came to be. Unfortunately, rich as it is, the fossil record only readily preserves form; the bones (and on rare occasions soft tissues) that make up an animal's anatomy. Function - the animal's behavior, lifestyle and ecology - must therefore be inferred. These inferences are based on form-function relationships established in living taxa, for which functional data should be readily available. However, there is still much we do not know about the inner workings of modern vertebrates, which limits what we can reliably infer from fossils. Here, I will discuss the functional and anatomical transformation of different body systems in vertebrates during three major evolutionary transitions; feeding across the "water-land" transition and the origin of terrestrial tetrapods; breathing across the "land-air" transition and the origins of birds; and locomotion (particularly forelimb use) across the "sprawling-erect" transition during the evolution of mammals. In each case, new biomechanical or anatomical data from related species which are still alive today has forced us to re-evaluate previous hypotheses on how these transitions occurred and altered or refined our interpretations of the fossil record. Modern biomechanical simulation and experimental tools are offering unprecedented insights into how skeletal form relates to whole-animal function; insights that can readily be applied to the fossil record in order to better understand organismal evolution in deep time.