Cryptic lineages respond differently to coral bleaching

Coral cover is decreasing worldwide largely as a result of a rise in seawater temperatures that triggers coral bleaching and induces coral mortality. How coral reefs will respond to climate change will be a function of genetic variation and how it is partitioned within and among species. A critical initial step is to accurately delineate species and quantify their physiological potential to cope with heat stress. Cryptic species are morphologically similar but genetically distinct and may respond physiologically different to climate change. A dominant Caribbean reef builder severely affected by climate change is the mountainous star coral, Orbicella faveolata. Recently, Dziedzic et al. (2019) reported quantitative genetic variation in the physiological response to thermal stress in a single population of this species, suggesting that variation within populations will allow these corals to adapt to rising ocean temperatures. We reanalyzed their data and found multiple cryptic lineages ra...全球范围内的珊瑚覆盖率正大幅下降，其主要诱因是海水温度升高——这一现象会引发珊瑚白化并导致珊瑚死亡。珊瑚礁对气候变化的响应方式，将取决于遗传变异情况，以及该变异在物种内部和物种间的分布模式。首要且关键的一步，是精准界定物种种类，并量化其应对热胁迫的生理潜力。隐存种（cryptic species）在形态上相似，但遗传特征截然不同，其对气候变化的生理响应可能存在差异。受气候变化严重影响的加勒比海优势造礁物种为山状星珊瑚（Orbicella faveolata）。近期，Dziedzic等人（2019年）在该物种的单个种群中，报道了其应对热胁迫的生理响应存在数量遗传变异，这表明种群内部的遗传变异可使这类珊瑚适应不断升高的海洋温度。我们对其数据进行了重新分析，发现了多个隐存进化支系……