29 Jan (GEOL) Jood Al Aswad, Paleobiology
Speaker: Jood Al Aswad, Virginia Tech
Time: Thu, 29 Jan, 4:30pm ET
Location: Exploratory 1309 and via Zoom (for link, email lhinnov@gmu.edu)
Title: Environmental and ecological controls on the global taxonomic homogenization of marine communities in deep time
Abstract: Rapid shifts in global biogeography are commonly attributed to environmental and ecological drivers, but their relative roles and interactions remain poorly tested. In this talk, I explore taxonomic homogenization, a pattern in which biological communities become increasingly similar in species composition through time. I focus on marine invertebrate communities following the end- Permian mass extinction (~ 252 million years ago), the most severe biodiversity crisis in Earth history. By integrating paleontological data; geochemical proxy records and oceanographic models of ocean temperature and oxygenation; and physiological data on organismal tolerance to temperature and oxygen; a mechanistic model is provided to explain the global taxonomic homogenization observed in the immediate aftermath of the extinction: As oceans became more uniformly hot and oxygen-poor, surviving taxa with physiological tolerances to those conditions were able to expand their aerobic habitats, leading to increasingly similar communities worldwide. Comparisons among several other intervals across deep time that experienced extinction; climate change; both; or neither reveal that global taxonomic homogenization in the oceans arises from the combined effects of environmental and ecological drivers.
Bio: Jood Al Aswad is a quantitative paleobiologist, and her research integrates paleobiology with information from oceanography, animal physiology, geochemistry, and stratigraphy to examine how ancient and modern marine invertebrate ecosystems respond to environmental change. She began her academic journey right here at George Mason University, where she earned a BS in Earth Science before attaining an MS in Geological Sciences from Cornell University and a PhD in Geological Sciences from Stanford University. Currently, she is a postdoctoral associate at Virginia Tech.
