Physical Sciences and Mathematics | Open Access Articles

Physiological Integration Of Coral Colonies Is Correlated With Bleaching Resistance, Timothy D. Swain, Emily C. Bold, Phillip C. Osborn, Andrew H. Baird, Mark W. Westneat, Vadim Backman, Luisa A. Marcelino

Timothy Swain

Inter-module physiological integration of colonial organisms can facilitate colony-wide coordinated responses to stimuli that strengthen colony fitness and stress resistance. In scleractinian corals, whose colonial integration ranges from isolated polyps to a seamless continuum of polyp structures and functions, this coordination improves responses to injury, predation, disease, and stress and may be one of the indications of an evolutionary origin of Symbiodinium symbiosis. However, observations of species-specific coral bleaching patterns suggest that highly integrated coral colonies may be more susceptible to thermal stress, and support the hypothesis that communication pathways between highly integrated polyps facilitate the dissemination of toxic byproducts …

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Skeletal Light-Scattering Accelerates Bleaching Response In Reef-Building Corals, Timothy D. Swain, Emily Dubois, Andrew Gomes, Valentina P. Stoyneva, Andrew J. Radosevich, Jillian Henss, Michelle E. Wagner, Justin Derbas, Hannah Grooms, Elizabeth M. Velazquez, Joshua Traub, Brian J. Kennedy, Arabela A. Grigorescu, Mark W. Westneat, Kevin Sanborn, Shoshana Levine, Mark Schick, George Parsons, Brendan C. Briggs, Jeremy D. Rogers, Vadim Backman, Luisa A. Marcelino

Timothy Swain

Background At the forefront of ecosystems adversely affected by climate change, coral reefs are sensitive to anomalously high temperatures which disassociate (bleaching) photosynthetic symbionts (Symbiodinium) from coral hosts and cause increasingly frequent and severe mass mortality events. Susceptibility to bleaching and mortality is variable among corals, and is determined by unknown proportions of environmental history and the synergy of Symbiodinium- and coral-specific properties. Symbiodinium live within host tissues overlaying the coral skeleton, which increases light availability through multiple light-scattering, forming one of the most efficient biological collectors of solar radiation. Light-transport in the upper ~200 μm layer …

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Modulation Of Light-Enhancement To Symbiotic Algae By Light-Scattering In Corals And Evolutionary Trends In Bleaching, Luisa A. Marcelino, Mark W. Westneat, Valentina P. Stoyneva, Jillian Henss, Jeremy Rogers, Andrew J. Radosevich, Vladimir Turzhitsky, Margaret Siple, Andrew Fang, Timothy D. Swain, Jennifer Fung, Vadim Backman

Timothy Swain

Calcium carbonate skeletons of scleractinian corals amplify light availability to their algal symbionts by diffuse scattering, optimizing photosynthetic energy acquisition. However, the mechanism of scattering and its role in coral evolution and dissolution of algal symbioses during “bleaching” events are largely unknown. Here we show that differences in skeletal fractal architecture at nano/micro-lengthscales within 96 coral taxa result in an 8-fold variation in light-scattering and considerably alter the algal light environment. We identified a continuum of properties that fall between two extremes: (1) corals with low skeletal fractality that are efficient at transporting and redistributing light throughout the colony with …

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Language Learning Under Classroom Conditions During The Transition To Hybrid Instruction: A Case-Study Of Student Performance During The Implementation Of Instructional Technology, Lisbeth O. Swain, Timothy D. Swain

Timothy Swain

We examined the unmanipulated performance of students under real classroom conditions in order to assess the effect of a technology-enhanced hybrid learning approach to second language, (L2) instruction on beginning and advanced Spanish language learners. This research focused on the transition period of technology implementation when the entire section of Spanish of a modern language department of a liberal arts university transitioned from traditional face-to-face instruction, to a technology-enhanced hybrid learning approach with concurrent reduction in face-to-face classroom hours. This implementation provided an opportunity to compare the performance of students prior to and during the transition to hybrid model of …

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Full-Text Articles in Physical Sciences and Mathematics

Physiological Integration Of Coral Colonies Is Correlated With Bleaching Resistance, Timothy D. Swain, Emily C. Bold, Phillip C. Osborn, Andrew H. Baird, Mark W. Westneat, Vadim Backman, Luisa A. Marcelino

Timothy Swain

Timothy Swain

Timothy Swain

Language Learning Under Classroom Conditions During The Transition To Hybrid Instruction: A Case-Study Of Student Performance During The Implementation Of Instructional Technology, Lisbeth O. Swain, Timothy D. Swain

Timothy Swain