Department of Biological Sciences, University of Southern California, 3616 Trousdale Parkway, Los Angeles, CA 90089, United States of America.
Department of Biological Sciences, University of Southern California, 3616 Trousdale Parkway, Los Angeles, CA 90089, United States of America.
Comp Biochem Physiol A Mol Integr Physiol. 2019 Dec;238:110562. doi: 10.1016/j.cbpa.2019.110562. Epub 2019 Sep 4.
The planktonic larval phase of scleractinian coral life-history represents a crucial stage when dispersal takes place and genetic diversity among populations is maintained. Understanding the dynamics influencing larval survival is especially relevant in the context of climate change, as larvae may be more vulnerable to environmental disturbances than adults. Several physiological parameters of coral larvae have been shown to vary by release time and past environmental history. However, the contribution of parental or genetic effects is largely unknown. To investigate these potential familial effects, we collected adult Porites astreoides colonies in April 2018 from two reef zones in the lower Florida Keys and quantified physiological traits and thermal tolerance of the newly released larvae. Family accounted for more variation than day of release and reef origin, with >60% of the variation in chlorophyll a and protein content explained by family. The survivorship of larvae under 36 °C acute temperature stress was also tightly linked to what parent colony they were released from. During a 32 °C moderate temperature stress experiment, inshore larvae tended to bleach less than offshore larvae, mirroring the enhanced bleaching resistance previously observed in inshore adult coral populations. The significant familial effects identified in the present study suggest that researchers should be cautious when interpreting results of studies which pool larvae among families, and that future studies should take care to account for this variation.
造礁石珊瑚浮游幼虫阶段是其生活史中的关键阶段，在此阶段珊瑚进行扩散，种群间的遗传多样性得以维持。了解影响幼虫存活的动态变化在气候变化的背景下尤为重要，因为幼虫可能比成体更容易受到环境干扰。已有研究表明，珊瑚幼虫的几个生理参数会随释放时间和过去的环境历史而变化。然而，父母或遗传效应的贡献在很大程度上仍是未知的。为了研究这些潜在的家族效应，我们于 2018 年 4 月在佛罗里达群岛的两个礁区收集了成年石珊瑚 Porites astreoides 群体，并量化了新释放幼虫的生理特征和耐热性。结果表明，家族比释放日期和礁区起源解释了更多的变异，叶绿素 a 和蛋白质含量的变异中有超过 60%可以用家族来解释。幼虫在 36°C 急性温度胁迫下的存活率也与它们来自的母群体紧密相关。在 32°C 的温和温度胁迫实验中，近岸幼虫的白化程度比近海幼虫低，这与先前在近岸成年珊瑚种群中观察到的增强的抗白化能力相呼应。本研究中确定的显著的家族效应表明，研究人员在解释将幼虫混合在一起的研究结果时应谨慎，并且未来的研究应注意到这种变异。
