Jan 12
Biology Seminar: Sebastian Schreiber, Professor of Evolution and Ecology, University of California, Davis, “When do environmental rhythms alter ecological outcomes?”
We live in a world where environmental conditions are constantly changing: some years are warmer than others, some days are wetter than other days. It is well-known that this environmental variation can result in population declines or mediate coexistence between competing species. However, it is less well-known how the rhythm of this environmental variation impacts ecological outcomes. In this talk, Professor Schreiber will show that the temporal structure of environmental fluctuations—not just their magnitude—can fundamentally alter ecological outcomes. For competing species, positive autocorrelation in environmental conditions can promote coexistence while negative autocorrelations can generate alternative stable states. For structured populations, the tempo and mode of environmental change (random versus periodic) can determine whether populations persist or go extinct. Together, these results suggest that understanding when and how environments fluctuate may be just as important as understanding that they fluctuate.