Long-term thermal history, not short-term exposure to different variability regimes, drives heatwave tolerance in key reef calcifiers

Long-term thermal history, not short-term exposure to different variability regimes, drives heatwave tolerance in key reef calcifiers | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Long-term thermal history, not short-term exposure to different variability regimes, drives heatwave tolerance in key reef calcifiers Erik Krieger, Lauren Tisdale, Fleur Bruggemann, Lena Li, Gage Mele, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7647146/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Exposure to fluctuating seawater temperatures can increase tolerance of some tropical corals to marine heatwaves. Whether similar variability can influence tolerance in other key calcifying taxa, such as reef-building algae, remains unknown. We experimentally tested whether diurnal temperature variability enhances heatwave tolerance in four species of tropical calcifying algae, and whether responses differ depending on the occurrence of peak temperatures during the day versus the night. Heatwave exposure suppressed calcification and photophysiological performance in three of the four species, and neither temperature variability, nor the timing of peak thermal exposure, significantly altered this response. These results suggest that the thermal tolerance of the study species is controlled by long-term acclimatization rather than by short-term exposure to different variability regimes. Nonetheless, the metabolic suppression induced by the heatwave demonstrates a poorly understood degree of vulnerability in this functional group. Despite these impacts, the algal species demonstrated greater resilience to heat stress than many reef-building corals likely would under equivalent conditions (7–10 Degree Heating Weeks). Differential thermal susceptibility among reef-building taxa, including potentially greater resilience in some algal species, may strongly influence the ecological trajectories of tropical reef communities as heatwaves increase in frequency and intensity. Biological sciences/Ecology/Ecophysiology Biological sciences/Ecology/Climate-change ecology Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SIDiurnalvariabilityandMHWtolerance.pdf SI for Krieger_et_al Long-term thermal history, not short-term exposure to different variability regimes, drives heatwave tolerance in key reef calcifiers Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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