Meeting Abstract

P3-9   -   Mechanistic basis of genotype-specific differences in the physiological response of the coral Acropora cervicornis to climate change related stressors Dilworth, J*; Million, W; Ruggeri, M; Hall, ER; Dungan, A; Muller, E; Kenkel, CD; University of Southern California; University of Southern California; University of Southern California; Mote Marine Laboratory; The University of Melbourne; Mote Marine Laboratory; University of Southern California jdilwort@usc.edu

Coral reefs are in decline globally due to the effects of climate change. Increasing sea surface temperatures and ocean acidification are likely to impact the recovery of coral reefs in the Florida Keys, where anthropogenic impacts have already contributed to the deterioration of these ecosystems in recent decades. Understanding how increased temperatures and ocean acidification interact and affect the physiology of corals and the mechanistic basis of these effects will be key to developing effective interventions to restore coral populations in a changing climate. We conducted a 2-month aquaria-based experiment to quantify the individual and combined effects of increased temperatures and pCO2 on 10 genotypes of the endangered coral Acropora cervicornis, a key species in coral restoration efforts. Previous work showed that the combined stressors often caused greater reductions in host, symbiont, and holobiont physiological functioning than temperature or acidification stress alone. There was significant genetic variation for most traits, and no significant negative correlations were found for any measured metrics. This suggests there are no significant trade-offs between adaptation to temperature and acidification stress, and some level of resistance to these threats is already present among genotypes used in restoration. To understand the underlying mechanisms of these physiological responses, we will use weighted gene co-expression analysis of RNA-seq data to quantify the effects of genotype and treatment on gene expression patterns in addition to examining correlations with higher order physiological traits. Understanding the mechanistic basis of differential physiological responses to stress will be essential to leveraging existing adaptive diversity to increase the resistance of restored coral populations.