Collaborative research: Coral community resilience: testing the role of hidden diversity in Pocilloporid corals at Mo'orea

Understanding how diversity influences ecological resilience is a fundamental research question, and one that is of central importance for predicting and managing the biological effects of global change. Among reef-building corals, diversity is often studied in terms of differences in morphology or life history among species defining the roles of live coral cover in supporting fish and invertebrate communities, community net calcification, buffer zones for coastal areas, and nutrient cycles (e.g., functional diversity). However, several studies have advocated that community resilience also critically depends on species with similar morphological or life history traits that respond in contrasting ways to disturbance or environmental heterogeneity (response diversity). Response diversity is provides ?ecological insurance?, where the absence or loss of any one species may be compensated by the presence of other species with similar morphological or life history traits that perform similar functions. An important way that similar species can exhibit differential responses to disturbance is through spatial and temporal heterogeneity in the recruitment, colony growth, survival, and population growth rates of different species. Direct evidence for the effects of response diversity among scleractinian corals on the ecological resilience of coral communities is sparse and equivocal, perhaps due in part to inconsistent species identification and corals with similar gross morphology being classified as a single species. Recent studies in many coral taxa using genetic and genomic data to delineate species have uncovered and redefined species diversity within functional groups of scleractinians, but we still have very little understanding of the extent to which this so-called ?hidden? diversity involves taxa displaying divergence in ecological traits, that are not necessarily linked to gross morphology or general life history, and leads to ecological resilience, as predicted by the concept of response diversity. Using the coral reefs of Mo?orea, French Polynesia, and the Mo?orea Coral Reef (MCR) LTER as a study location and model system, our objective is to understand the roles played by ecological differences among multiple coral species with similar morphology in driving recovery of coral communities on shallow reefs exposed to disturbances. We will test if morphologically similar pocilloporid species have divergent ecological traits, and how multiple species or a few species drive recovery of ecologically dominant scleractinians on the reefs of Mo?orea following disturbances.