Spinks Rachel K, Bonzi Lucrezia C, Ravasi Timothy, Munday Philip L, Donelson Jennifer M
ARC Centre of Excellence for Coral Reef Studies James Cook University Townsville Queensland Australia.
Red Sea Research Center Division of Biological and Environmental Sciences and Engineering King Abdullah University of Science and Technology Thuwal Saudi Arabia.
Evol Appl. 2021 Jan 13;14(4):1145-1158. doi: 10.1111/eva.13187. eCollection 2021 Apr.
Global warming can disrupt reproduction or lead to fewer and poorer quality offspring, owing to the thermally sensitive nature of reproductive physiology. However, phenotypic plasticity may enable some animals to adjust the thermal sensitivity of reproduction to maintain performance in warmer conditions. Whether elevated temperature affects reproduction may depend on the timing of exposure to warming and the sex of the parent exposed. We exposed male and female coral reef damselfish () during development, reproduction or both life stages to an elevated temperature (+1.5°C) consistent with projected ocean warming and measured reproductive output and newly hatched offspring performance relative to pairs reared in a present-day control temperature. We found female development in elevated temperature increased the probability of breeding, but reproduction ceased if warming continued to the reproductive stage, irrespective of the male's developmental experience. Females that developed in warmer conditions, but reproduced in control conditions, also produced larger eggs and hatchlings with greater yolk reserves. By contrast, male development or pairs reproducing in higher temperature produced fewer and poorer quality offspring. Such changes may be due to alterations in sex hormones or an endocrine stress response. In nature, this could mean female fish developing during a marine heatwave may have enhanced reproduction and produce higher quality offspring compared with females developing in a year of usual thermal conditions. However, male development during a heatwave would likely result in reduced reproductive output. Furthermore, the lack of reproduction from an average increase in temperature could lead to population decline. Our results demonstrate how the timing of exposure differentially influences females and males and how this translates to effects on reproduction and population sustainability in a warming world.
由于生殖生理对温度敏感的特性，全球变暖会干扰繁殖或导致后代数量减少且质量下降。然而，表型可塑性可能使一些动物能够调节繁殖的温度敏感性，以在更温暖的条件下维持繁殖性能。温度升高是否会影响繁殖可能取决于暴露于变暖的时间以及受影响亲代的性别。我们在发育、繁殖或两个生命阶段将雄性和雌性珊瑚礁雀鲷暴露于与预计海洋变暖相符的升高温度（+1.5°C）下，并相对于在当前对照温度下饲养的配对，测量了繁殖输出和新孵化后代的性能。我们发现，在升高温度下发育的雌性增加了繁殖的可能性，但如果变暖持续到生殖阶段，繁殖就会停止，而与雄性的发育经历无关。在较温暖条件下发育但在对照条件下繁殖的雌性也会产出更大的卵和具有更多卵黄储备的幼体。相比之下，在较高温度下发育的雄性或配对产出的后代数量更少且质量更差。这种变化可能是由于性激素的改变或内分泌应激反应。在自然界中，这可能意味着与在正常温度年份发育的雌性相比，在海洋热浪期间发育的雌性鱼类可能繁殖能力增强并产出更高质量的后代。然而，热浪期间雄性的发育可能会导致繁殖输出下降。此外，温度平均升高导致繁殖停止可能会导致种群数量下降。我们的结果表明了暴露时间如何对雌性和雄性产生不同影响，以及这如何转化为对变暖世界中繁殖和种群可持续性的影响。
