Wednesday, February 1, 2017
1403 Solano Ave, Albany, CA
Mass extinctions – episodes during which many groups of previously successful organisms disappeared from Earth in a geologically short timespan – are one of the most striking and earliest recognized features of the fossil record. As the modern biodiversity crisis unfolds, scientists are increasingly turning to these events to understand the relationship between environmental changes and biodiversity losses. Yet despite decades of study, many questions about the causes and consequences of mass extinctions remain open.
Dr. Finnegan will talk about the history of thinking about mass extinctions, the different kinds of information that paleontologists and geologists draw on to understand them, and some of the current debates surrounding them. He will touch on several major events, including his work on the first major mass extinction: the Late Ordovician Mass Extinction, 445 million years ago.
Seth Finnegan is broadly interested in the processes that have shaped the composition of the marine biota and the development of marine ecosystems from the origin of animals in the late Neoproterozoic to the present day. Research in his lab integrates data from a variety of sources including field observations, lab work, and literature databases to ask and answer questions about the nature of organism-environment interactions through time. He is particularly interested in (1) Patterns of extinction selectivity, and what they can tell us about the changing drivers of the extinction process and how differential extinction has shaped evolution through time, (2) Using environmental proxy data (stable isotopes, biomarkers, stratigraphy) to understand the physical context of major evolutionary and ecological events recorded by the fossil record, and (3) Developing taxon-free methods to reconstruct the structure and function of marine ecosystems (e.g. as energy- and nutrient-exchange networks) through time.