Join us for this week's Bio at Noon seminar, featuring Dr. Carlos Prada (URI)

Title:  Adaptation across environmental variation in corals: Past and Present

Abstract: 
"Darwin proposed that biodiversity evolves by natural selection, yet geneticists have traditionally stressed the role of physical isolation during evolution.  Local adaptation, the thinking has gone, occurs when environmental differences among populations appear at distances greater than organisms can disperse. Looking at populations of long-lived corals, I will show how adaptation and divergence occurs between colonies separated by just a couple of hundred meters. I will show how coral larvae (with a dispersal potential of > 50 km) reach both shallow and deep habitats but over time natural selection weed out maladapted juveniles. I will present results on how limited recruitment to reproductive age, even under weak annual selection, is sufficient to generate habitat segregation because of the cumulative prolonged pre-reproductive selection. I will conclude the first part of the talk by emphasizing how ecological factors act as filters generating strong barriers to gene flow, altering morphologies, and contributing to the potential for speciation in the sea. In the second part of the talk, I will discuss the evolutionary potential of corals to adapt to ongoing climate change. I will present analysis of previously unknown current and past population sizes in corals, how coral populations have survived drastic changes in climatic conditions and even bypass extinction events. I will blend paleontological and ecological observations, transplant experiments and genomic reconstructions using whole genome sequencing. The focus of my talk will be on the ESA-threatened mountainous coral Orbicella faveolata and the candelabrum Eunicea flexuosa from the Caribbean."