Ocean Acidification:Collaborative Research: Effects of Ocean Acidification on Larval Competence, Metamorphosis, and Juvenile Performance in a Planktotrophic Gastropod

空气中的二氧化碳含量比200年前工业革命开始时高出约40%。 至少有1/3的过量二氧化碳被海洋吸收，使其酸性更强，因为二氧化碳形成碳酸。 了解这种海洋酸化（OA）对海洋动物和生态系统的可能影响是复杂的，因为环境的其他特征预计也会发生明显变化（例如，海水温度会上升，食物供应和营养价值可能下降），因为早期发育过程中经历的压力可能产生持久影响，而且对这些反应的分子机制知之甚少。 本研究探讨了OA在不同的环境条件下将如何影响海洋蜗牛Crepidula fornicata的发育，扩散和变态，Crepidula fornicata是一种常见的原产于美国东部的物种，现已在太平洋西北部，欧洲和其他地方建立。 本研究将包括：1）OA对幼虫组织和壳生长的相对速率的影响; 2）幼虫暴露于OA对幼体存活和生长的长期影响; 3）OA对幼虫和幼体基因表达模式的影响; 4）OA对变态时间和对环境诱导物的变态反应能力的影响; 5）温度升高对OA反应的影响; 6）幼虫饮食对OA易感性的影响;以及7）OA对幼虫游泳能力和定居行为的影响。 该物种原产于美国东海岸，但现在已成为世界许多其他地区的重要入侵物种。这些结果将对了解该物种的持续传播具有重要意义。此外，这项工作还包括为研究生和本科生提供培训机会，与高中教师进行外联，并开发新的课堂练习。预计软体动物幼虫在未来几年特别容易受到海洋酸化（OA）的影响，因为它们的外壳钙化很薄。 此外，水温预计会放大OA的一些影响。 有些影响，如可能降低生长速度，减少壳厚度，改变扩散能力可能是立即的，而其他（潜在的影响）可能只出现在发展后期，变态发生后很久。 此外，OA-有或没有海洋变暖-可能会改变幼虫的行为和生理的方式，影响变态的时间和青少年的健身，从而改变分散的潜力和脆弱性捕食者。 OA也可能改变浮游植物的丰度和营养质量。 我们将调查OA的后果在不同的环境情景下的海洋腹足动物Crepidula fornicata，一个容易培养的物种，正在受到越来越多的关注，作为一个一般的模式lophotrochozoan发展和作为一个生态上重要的入侵者在底栖潮下带社区的幼虫。 我们的研究将包括：结果表明：OA对幼虫组织和壳生长速率的影响，OA对幼鱼存活和生长的潜在影响，OA对温度的影响，OA对幼虫和幼鱼基因表达的影响，OA对变态能力发育的影响，OA对幼鱼生长发育的影响。6）OA对有能力的幼虫对各种变态诱导剂的反应的影响; 7）幼虫饲料质量对OA的脆弱性的影响，无论是在幼虫阶段还是在变态之后（潜伏效应）;和8）OA对幼虫游泳和定居行为的影响，以及这些行为的神经相关性。

Levels of CO2 in the air are now about 40% higher than they were 200 years ago at the start of the Industrial Revolution. At least 1/3 of excess CO2 production has been absorbed by the ocean, making it more acidic as the CO2 forms carbonic acid. Understanding the likely impact of this increasing ocean acidification (OA) on marine animals and ecosystems is complicated by the fact that other features of the environment are also expected to change appreciably (e.g., seawater temperatures will increase and food availability and nutritional value may decline), by the fact that stresses experienced in early development can have lasting effects, and because the molecular mechanisms of the responses are poorly understood. This study examines how OA under different environmental conditions will impact the development, dispersal, and metamorphosis of the marine snail Crepidula fornicata, a common species native to the eastern U.S. that has now become established in the Pacific Northwest, Europe, and elsewhere. This study will include: 1) the impact of OA on relative rates of tissue and shell growth in larvae; 2) long-term impact of larval exposure to OA on the survival and growth of juveniles; 3) influence of OA on gene expression patterns in both larvae and juveniles; 4) impact of OA on time until metamorphosis and on the ability to metamorphose in response to environmental inducers; 5) effect of elevated temperature on responses to OA; 6) impact of larval diet on vulnerability to OA; and 7) impact of OA on larval swimming ability and settlement behavior. The study species is native to the East coast of the United States but has now become an important invasive in many other parts of the world. The results will have important implications for understanding the continued spread of this species. In addition, the work includes opportunities for graduate and undergraduate student training, outreach to high school teachers and development of new classroom exercises. Molluscan larvae are expected to be especially susceptible to the effects of ocean acidification (OA) in the coming years, due to their thinly calcified shells. In addition, water temperatures are expected to amplify some impacts of OA. Some effects, such as potentially reduced growth rates, reduced shell thickness, and altered dispersal capability are likely to be immediate, while others (latent effects) may appear only later in development, well after metamorphosis has taken place. In addition, OA--with or without ocean warming--may alter larval behavior and physiology in ways that affect the timing of metamorphosis and the fitness of juveniles,thus altering dispersal potential and vulnerability to predators. OA may also alter the abundance and nutritional quality of phytoplankton. We will investigate the consequences of OA under different environmental scenarios for larvae of the marine gastropod Crepidula fornicata, an easily cultured species that is receiving increasing attention both as a general model for lophotrochozoan development and as an ecologically significant invader in benthic subtidal communities. Our study will include: 1) impact of OA on rates of larval tissue and shell growth; 2) latent effects of larval exposure to OA on juvenile survival and growth; 3) effect of elevated temperature on responses to OA; 4) influence of elevated OA on larval and juvenile gene expression; 5) impact of OA on the development of competence for metamorphosis; 6) impact of OA on the response of competent larvae to a variety of metamorphic inducers; 7) impact of larval diet quality on vulnerability to OA, both in the larval stages and following metamorphosis (latent effects); and 8) impact of OA on larval swimming and settlement behaviors, and the neural correlates of those behaviors.