Modulation of Light-Enhancement to Symbiotic Algae by Light-Scattering in Corals and Evolutionary Trends in Bleaching

• DOI: 10.1371/journal.pone.0061492
• Publication Date: 2013-04-22T23:06:53Z
• Authors: Luisa A. Marcelino; Mark W. Westneat; Valentina Stoyneva; Jillian Henss; Jeremy D. Rogers; Andrew Radosevich; Vladimir Turzhitsky; Margaret Siple; Andrew Fang; Timothy D. Swain; Jennifer Fung; Vadim Backman
• Keywords: Coral bleaching; Symbiodinium; Zooxanthellae

Calcium carbonate skeletons of scleractinian corals amplify light availability to their algal symbionts by diffuse scattering, optimizing photosynthetic energy acquisition. However, the mechanism scattering and its role in coral evolution dissolution symbioses during "bleaching" events are largely unknown. Here we show that differences skeletal fractal architecture at nano/micro-lengthscales within 96 taxa result an 8-fold variation light-scattering considerably alter environment. We identified a continuum properties fall between two extremes: (1) with low fractality efficient transporting redistributing throughout colony scatter but higher risk bleaching (2) high inefficient lower bleaching. While levels excess derived from skeleton is similar both groups, low-scatter have rate light-amplification increase when symbiont concentration reduced bleaching, thus creating positive feedback-loop exposes remaining increasingly intensities. By placing our findings evolutionary framework, conjunction novel empirical index susceptibility, find significant correlations susceptibility despite rich homoplasy characters; suggesting cost enhancing algae revealed decreased resilience partnership stress.