w/Randi Rotjan at Boston University

We are working to discern the reproductive energetic tradeoffs associated with a facultative symbiosis between the temperate coral, Astrangia poculata, and its single algal symbiont, Symbiodinium psygmophilum. A. poculata inhabits subtidal coastal waters from southern New England into the Gulf of Mexico. Environmental conditions, ecological parameters, and measures of organismal (i.e. colony) performance vary along this range. However, the most intriguing life history difference among colonies in this system is the fact that symbiotic state is facultative and adjacent colonies, seemingly subjected to the same environmental conditions, can be found with either numerous (=symbiotic), few (=aposymbiotic), or zero (=asymbiotic) associated algal symbionts.

w/Amy Moran at Clemson University (now at University of Hawaii)

We have long been interested in the effects that egg size, egg composition, and egg energy have on larval performance. In a large, comprehensive study we examined egg provisioning and larval growth in multiple geminate species pairs of sea urchins (in the genera Diadema, Echinometra, and Eucidaris). These species were separated by the closure of the Central American Seaway approximately 3.2 MYA and have been evolving in isolation since that time. This model system has facilitated our understanding of the evolution of egg size and its implications for a wide range of life history correlates among marine invertebrates. Our data set and sample collection are large and we are still finding novel insights.