Comparative Biogeography of Paleozoic Invertebrates

Authors: Julia Zottola, Michael A. Holowiak, Elizabeth B. Altier, Joseph E. Panzik, Jennifer E. Bauer, Adriane R. Lam, James C. Lamsdell, Sarah L. Sheffield

Field of Study: Biological Sciences

Faculty Mentors: Sarah Sheffield

Easel: 56

Timeslot: Afternoon

Abstract: Large climatic shifts occurred across the Paleozoic (541–251 million years ago), influencing evolutionary trajectories across Earth’s history. Herein, the biogeographic patterns of marine invertebrates published in previous analyses spanning the Paleozoic were studied through an evolutionary framework. These datasets were analyzed using various statistical methods, then combined with stratigraphic ranges and basins of origin from published literature. The evolutionary (phylogenetic) and stratigraphic data were incorporated together to infer time-calibrated evolutionary trees. The resulting phylogenetic estimations and associated biogeographic data were imported into the R package ‘BioGeoBEARS’ to perform a biogeographic analysis for each tree to examine range shifts, relationships, and speciation events. Results from the most statistically supported analyses were compared to explore the biogeographic patterns variations across different invertebrate groups, specifically looking at the dispersal to distinct basins, the rate and directions in which taxa dispersed, and when in time they occurred.