Thermal Sensitivity of Antarctic Embryos and Larvae: Effects of Temperature on Metabolism, Developmental Rate, and the Metabolic Cost of Development

南极海洋中的冷血动物在几乎不变的极端寒冷条件下生存了数百万年，对水温的微小变化都非常敏感。然而，这种极端的热敏感性对发育中的胚胎的能量、发育和存活的影响还没有被很好地理解。该奖项将研究温度对南极海洋外温动物胚胎和幼虫的新陈代谢、生长速度、发育速度和发育能量的影响。该项目还将测量麦克默多海湾不同地点温度和氧气的年变化，并比较冬季和夏季胚胎和幼虫的新陈代谢，以确定这些生命阶段适应季节性变化的程度。这项研究将为极地海洋动物和生态系统抵御极地海洋变暖的能力提供洞察力。南极海洋外温动物普遍生长缓慢，代谢率低，发育时间长，但它们的许多与生理和代谢有关的速率过程对温度高度敏感。这表明，温度的微小变化可能会导致能量新陈代谢、生长以及发育速度和持续时间的巨大变化。该项目将测量温度对四种常见的、具有生态重要性的南极底栖海洋无脊椎动物新陈代谢、发育速度和开发的能量成本的影响。这些影响将在生物体的功能范围内以及麦克默多海湾周围与环境相关的季节性温度变化的背景下进行测量。最近的资料表明，麦克默多站附近气温升高约1℃，伴随着影响近岸边界层底栖生物的长期高氧事件。这项研究将更全面地了解海湾地区环境氧气和温度的年度变化，以及这种变化是否会导致与生理适应一致的发育速度和能量变化。这些数据将提供有关南极外温带变暖的潜在影响的关键信息。此外，该项目将支持本科生和研究生研究，并与ANNH和AANAPISI Title III少数群体服务机构的大招生本科课程和REU项目合作。该奖项反映了NSF的法定使命，通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Cold-blooded animals in the Antarctic ocean have survived in near-constant, extreme cold conditions for millions of years and are very sensitive to even small changes in water temperature. However, the consequences of this extreme thermal sensitivity for the energetics, development, and survival of developing embryos is not well understood. This award will investigate the effect of temperature on the metabolism, growth rate, developmental rate, and developmental energetics of embryos and larvae of Antarctic marine ectotherms. The project will also measure annual variation in temperature and oxygen at different sites in McMurdo Sound, and compare embryonic and larval metabolism in winter and summer to determine the extent to which these life stages can acclimate to seasonal shifts. This research will provide insight into the ability of polar marine animals and ecosystems to withstand warming polar ocean conditions.Antarctic marine ectotherms exhibit universally slow growth, low metabolic rates, and extended development, yet many of their rate processes related to physiology and metabolism are highly thermally sensitive. This suggests that small changes in temperature may result in dramatic changes to energy metabolism, growth, and the rate and duration of development. This project will measure the effects of temperature on metabolism, developmental rate, and the energetic cost of development of four common and ecologically important species of benthic Antarctic marine invertebrates. These effects will be measured over the functional ranges of the organisms and in the context of environmentally relevant seasonal shifts in temperature around McMurdo Sound. Recent data show that seasonal warming of ~1 deg C near McMurdo Station is accompanied by long-lasting hyperoxic events that impact the benthos in the nearshore boundary layer. This research will provide a more comprehensive understanding of both annual variation in environmental oxygen and temperature across the Sound, and whether this variation drives changes in developmental rate and energetics that are consistent with physiological acclimatization. These data will provide key information about potential impacts of warming Antarctic ectotherms. In addition, this project will support undergraduate and graduate research and partner with large-enrollment undergraduate courses and REU programs at an ANNH and AANAPISI Title III minority-serving institution.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.