Physiological ecology of intertidal development: linking embryo performance and adult reproductive ecology

潮间带发育的生理生态学：连接胚胎性能和成体生殖生态学在海洋栖息地中，潮间带的变化是极端的：潮汐产生了一系列的物理变化，这些变化不仅改变了环境条件的平均值和方差，而且改变了暴露于压力的频率。对于在这些栖息地发育的物种来说，生存和生长取决于胚胎建立的生化防御，或者取决于成虫选择的繁殖时间或地点。产卵的适应性结果随时间和空间的变化而变化，但成年人对胚胎将面临的未来条件的信息并不完善。虽然成年人的反应有很好的特征，但我们对早期阶段的变异性或压力的后果知之甚少，这对身体条件特别敏感，通常代表着生活史的瓶颈。本项目是潮间带繁殖与发育生理生态学的综合性研究项目。软体动物Melanochlamys diomedea的卵群被拴在沙滩表面的潮池中，在那里它们经历了潮汐交换内部和之间高度变化的发育条件。该物种提供了一个敏感和易于处理的系统，将胚胎生理、生长和存活与实验室和野外的环境变化和压力条件联系起来。此外，跟踪与环境条件相关的成年生殖产出的能力可以检验生殖模式是否具有可塑性和适应性。具体而言，(1)解决胚胎应激蛋白表达的发育和生态条件。将确定在不同季节和不同温度生境收集的胚胎的温度阈值和应激蛋白诱导的发育开始。(2)测量温度变化和应激对发育性能的影响。胚胎将暴露在受控的温度剖面中，以区分温度平均值、方差、应激水平和变化率对生产性能的贡献。(3)估算野外条件下温度变化对发育的影响。将卵块短期暴露于野外条件和紫外线操作将用于模拟温度和紫外线自然变化对发育的影响。(4)评价成虫繁殖时间对发育成功的贡献。该领域的成人生殖模式将用于检验生殖时间是非随机的、与环境条件相关的、对后代有益的假设。知识价值。潮间带栖息地为了解生态条件对海洋发展和生命史进化的影响提供了一个独特的场所。由于早期阶段对自然条件很敏感，并且往往是海洋种群动态的瓶颈，因此在潮间带地区繁殖的种群可能特别容易受到环境挑战的影响。该项目开发了一种独特的方法来理解高度相关的海洋环境中环境变异性、发育生理学和生殖生态学的交叉。它整合了有关应激保护机制、发育性能、野外条件和繁殖时间的信息，以了解生命周期中两个不同但功能相关的阶段对变异性和应激的反应。通过将发育建模为自然条件变化的函数，它对成年生殖决策的适应性结果做出了明确的预测，并进行了测试。由于温度稳定性是海洋发育的主导范式，对自然变率响应的研究将进一步加深我们对海洋早期生活史的基本发育生物学和生理生态学的理解。更广泛的影响。提出的研究和教育目标为处于不同教育阶段的学生创造了参与综合研究的机会。参与FHL眨眼指导计划将允许少数民族学生定期参加PI的实验室和部门荣誉研究计划。与FHL的K-12教育协调员合作，将提供一个机会，开发实验、探究和注重环境的小学学习练习。最后，参与FHL的发育生物学家和海洋生态学家社区将有助于PI和研究生促进生态背景下海洋发展的知识交流、综合和教学。编辑6/3/04 - JRP

Physiological ecology of intertidal development: linking embryo performance and adult reproductive ecologyAmong marine habitats, intertidal areas are extreme in their variability: tides create a suite of physical changes that alter not only the mean and variance of environmental conditions, but also the frequency of exposure to stress. For species that develop in these habitats, survival and growth depend on biochemical defenses mounted by embryos or on the selective timing or location of reproduction by adults. Fitness consequences of spawning vary in time and space, but adults have imperfect information about future conditions that embryos will face. While adult responses are well-characterized, we know relatively little about consequences of variability or stress for early stages, which are especially sensitive to physical conditions and often represent a life-history bottleneck. This project is an integrative research program in the physiological ecology of intertidal reproduction and development. Egg masses of the mollusc Melanochlamys diomedea are tethered in tide pools on the surface of sand flats, where they experience developmental conditions that are highly variable within and between tidal exchanges. This species provides a sensitive and tractable system to relate embryo physiology, growth and survival, in both the lab and field, to conditions of environmental variability and stress. In addition, the ability to track adult reproductive output relative to environmental conditions allows tests of whether reproductive patterns are plastic and adaptive. Specifically, (1) To resolve developmental and ecological conditions for embryonic stress protein expression. Temperature thresholds and the developmental onset of stress protein induction in embryos collected in different seasons and from thermally distinct habitats will be determined. (2) To measure effects of temperature variability and stress on developmental performance. Embryos will be exposed to controlled temperature profiles to distinguish the contributions to performance of temperature mean, variance, stress level, and rate of change. (3) To estimate the developmental consequences of temperature variability under field conditions. Short-term exposure of egg masses to field conditions and manipulation of UV will be used to model the developmental consequences of natural variation in temperature and UV. (4) To evaluate the contribution of adult reproductive timing to developmental success. Adult reproductive patterns in the field will be used to test the hypotheses that the timing of reproduction is non-random, correlated with environmental conditions, and beneficial to offspring. Intellectual merit. Intertidal habitats offer a unique arena for understanding the impact of ecological conditions on marine development and life-history evolution. Because early stages are sensitive to physical conditions, and often represent a bottleneck in marine population dynamics, populations that reproduce in intertidal areas may be especially vulnerable to environmental challenges. This project develops a unique approach to understanding the intersection of environmental variability, developmental physiology, and reproductive ecology in a highly relevant marine environment. It integrates information on mechanisms of stress protection, developmental performance, field conditions, and reproductive timing to understand responses to variability and stress at two distinct but functionally-linked phases of the life cycle. By modeling development as a function of variation in natural conditions, it makes and tests explicit predictions about the fitness consequences of adult reproductive decisions. Because temperature stability is the dominant paradigm in marine development, research on responses to natural variability will further our understanding of both basic developmental biology and the physiological ecology of marine early life histories. Broader impacts. The proposed research and educational goals create opportunities for students at several stages of education to participate in integrative research. Involvement with the FHL Blinks Mentorship program will allow regular participation of minority students in the PI's lab and in the department honors research program. Work with the K-12 education coordinator at FHL will provide an opportunity to develop experimental, inquiry-based and environmentally-focused primary school learning exercises. Finally, participation in the community of developmental biologists and marine ecologists at FHL will help the PI and graduate students to promote intellectual exchange, synthesis, and teaching about marine development in an ecological context. Edited 6/3/04 - JRP