Leach Terence S, Hofmann Gretchen E
Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA, United States.
Front Physiol. 2023 Aug 4;14:1230590. doi: 10.3389/fphys.2023.1230590. eCollection 2023.
Marine heatwave (MHW) events, characterized by periods of anomalous temperatures, are an increasingly prevalent threat to coastal marine ecosystems. Given the seasonal phenology of MHWs, the full extent of their biological consequences may depend on how these thermal stress events align with an organism's reproductive cycle. In organisms with more complex life cycles (e.g., many marine invertebrate species) the alignment of adult and larval environments may be an important factor determining offspring success, setting the stage for MHW events to influence reproduction and development . Here, the influence of MHW-like temperatures on the early development of the California purple sea urchin, , were explored within the context of paternal thermal history. Based on temperature data collected during MHW events seen in Southern California from 2014-2020, adult urchins were acclimated to either MHW or non-MHW temperatures for 28 days before their sperm was used to produce embryos that were subsequently raised under varying thermal conditions. Once offspring reached an early larval stage, the impact of paternal and offspring environments were assessed on two aspects of offspring performance: larval size and thermal tolerance. Exposure to elevated temperatures during early development resulted in larger, more thermally tolerant larvae, with further influences of paternal identity and thermal history, respectively. The alignment of paternal and offspring exposure to MHW temperatures had additional positive benefits on larval thermal tolerance, but this tolerance significantly decreased when their thermal experience mismatched. As the highest recorded temperatures within past MHW events have occurred during the gametogenesis of many kelp forest benthic marine invertebrate species, such as the purple sea urchin, such parental mediated impacts may represent important drivers of future recruitment and population composition for these species.
海洋热浪（MHW）事件以异常高温期为特征，对沿海海洋生态系统构成的威胁日益普遍。鉴于海洋热浪的季节性物候特征，其生物学后果的全面程度可能取决于这些热应激事件如何与生物体的繁殖周期相契合。在具有更复杂生命周期的生物体（例如许多海洋无脊椎动物物种）中，成体和幼体环境的契合可能是决定后代成功的一个重要因素，为海洋热浪事件影响繁殖和发育奠定了基础。在此，在父本热历史的背景下，探讨了类似海洋热浪温度对加利福尼亚紫海胆早期发育的影响。根据2014年至2020年在南加州观测到的海洋热浪事件期间收集的温度数据，将成年海胆在其精子用于产生胚胎之前，使其适应海洋热浪或非海洋热浪温度28天，随后将胚胎在不同的热条件下饲养。一旦后代达到早期幼虫阶段，就从后代性能的两个方面评估父本和后代环境的影响：幼虫大小和热耐受性。早期发育期间暴露于高温导致幼虫体型更大、热耐受性更强，分别受到父本身份和热历史的进一步影响。父本和后代暴露于海洋热浪温度的契合对幼虫热耐受性有额外的积极益处，但当它们的热经历不匹配时，这种耐受性会显著降低。由于过去海洋热浪事件中记录到的最高温度发生在许多海带森林底栖海洋无脊椎动物物种（如紫海胆）的配子发生期间，这种亲代介导的影响可能是这些物种未来补充和种群组成的重要驱动因素。
