Polycom available at the Darling Marine Center.
The School of Marine Sciences and the School of Biology and Ecology present
Dr. Mónica Medina
Pennsylvania State University
Coral holobiont members – which include the coral host, the algal symbiont and a poorly characterized consortium of diverse microbial
taxa – have different generation times and effective population sizes. These differences can have pronounced evolutionary and
ecological consequences for holobiont members, especially under a rapidly changing climate. Corals tend to have slow generation times
relative to their microbes, on the order of decades. Algal symbionts with different physiological adaptations to light and temperature are
known to shift in abundance within a host in response to perturbations (e.g., increasing SST) over months to years. Coral associated
prokaryotic microbial assemblages not only have very fast generation times, but their community composition can shift rapidly under
changing environmental conditions.
Metabolic complementary analysis has revealed a keystone role for the coral microbiome in holobiont homeostasis. We have performed
reciprocal transplant experiments and temperature stress time series on the Caribbean corals in the Orbicella species complex, and used
photobiology to examine coral fitness. These studies have uncovered differential mortality linked to locally adapted host/algal
genotypes. In these experiments, metagenomic and microbial diversity analysis have also revealed a significant response of the
microbiome to perturbation.
We have only scratched the surface of complex holobiont dynamics, yet these studies highlight the need for additional data and a
comprehensive theoretical framework that integrates ecological and evolutionary time scales.
Host: Susan Brawley