The degree to which an organism can plastically modify its morphology or physiology by changing gene expression helps set the range of environments to which it can acclimate. As an alternative to acclimation, organisms may deal with environmental differences by adaptive alteration of allele frequencies across generations. However, the same genomic changes that facilitate acclimation over ecological scales may provide substrate for change over evolutionary time. This project will study genes involved with acclimation and adaptation to depth in Caribbean corals. In candelabrum corals (genus Eunicea), variation in depth generates adaptive phenotypic differences that may lead to the formation of new species at different depths. This study will use transplanted fragments from coral colonies collected at and acclimated to different depths to measure plasticity in gene expression and test if two depth-segregated species have diverged in their acclimation response to depth. The proposed research represents an innovative attempt to evaluate the role of plasticity in providing initial variation during adaptive divergence of closely related species with different ecologies.
Understanding how organisms cope with environmental variation provides basic knowledge on how to implement restoration plans in changing ocean. This is of paramount importance for Caribbean reefs, where coral cover has decreased by > 80% since the eighties, coral bleaching is becoming more frequent, and the billion-dollar income it generates in Florida alone through recreation is in peril. PIs in this proposal will also continue engaging high school and undergraduate women with science.
