Seminar "SARS-Cov2 meets the ecological niche" by Dr. Robert Dan Holt

Speaker: Prof. Robert Dan Holt

Title: SARS-Cov2 meets the ecological niche

Affiliation: Affiliate Eminent Scholar, Center for African Studies, University of Florida, USA

Hosted by Dieckmann Unit

Venue: L4E01, Lab 4

*Zoom is available: https://oist.zoom.us/j/95598939235?pwd=nz81LVb2Bc8Z0eBsEjZipntLfsxFXa.1

Abstract:

This talk will weave together aspects of understanding the pandemic — and how a failure of such understanding led to degradation in public health responses around the globe — with  fundamental conceptual issues in ecology. The most basic concept in  ecology is exponential population growth and decline — which the pandemic clearly showed. But such growth rates can depend upon environmental conditions, an insight formalized in the Hutchinsonian niche. The ecological niche of pathogens is multiscale, because it involves processes within individual hosts, and in and among populations of hosts. Metapopulations can persist even if average growth rates of a population (births minus deaths) are everywhere negative, if there is temporal variability in growth rates among sites, that variability is sufficiently uncorrelated., and there is movement among sites. This is called an 'inflationary effect'. Known in general population ecology, there is good reason to think that it occurs and is important in epidemics. Successful public health regimes for COVID-19 push below unity the longterm regional Rt — the average number of secondary cases caused by an infectious individual. A susceptible-infectious-recovered (SIR) model for two coupled populations helps make the conceptual point that asynchronous, variable local control of transmission, together with movement between populations, elevates long-term regional Rt, and cumulative cases, and may even prevent disease eradication that is otherwise possible. There is empirical reason this believed to the failure of control of the covid pandemic. For effective pandemic mitigation strategies, it is critical that models encompass both spatiotemporal heterogeneity in transmission and movement. This effect illustrates how general metapopulation processes are at play and important for human well-being.

Biosketch:

Robert D. Holt is an ecologist particularly known for theoretical and conceptual contributions to population and community ecology, and for fostering the integration of ecology with evolutionary biology. His research examines how species interact, both directly and indirectly, in complex webs and he addresses the ecological and evolutionary consequences of such interactions, and how such interactions unfold across space, contributing for instance to geographical range limits. He was born and raised in Tennessee. He graduated from Princeton in 1973 with a degree in physics, but fortunately each semester took for fun an upper-level course in biology. This allowed him to pursue graduate studies in biology at Harvard, where he received his doctorate in 1979. He then moved to the University of Kansas, where he was on the faculty and a curator in the Museum of Natural History. In 2001 he shifted to the University of Florida to take the titles of Eminent Scholar and Arthur R. Marshal Jr. Chair in Ecological Studies. He is a Fellow of the American Academy of Arts and Sciences as well as the National Academy of Sciences, and has been president of the American Society of Naturalists. He is a keen naturalist and has participated in expeditions to many remote corners of the globe.