CAREER: Consequences of Short-Term Food Variability During the Development of Marine Invertebrate Larvae

大多数生活在海底的无脊椎动物都有复杂的生命周期，其中包括远洋幼虫。这些幼虫中的许多在发育、生长和分散到栖息地的过程中以浮游生物为食，在那里定居并蜕变为底栖幼虫。幼虫期的持续时间是任何运输和招募模式的核心。同样，变形期的规模也有助于新入职员工的成功。长期以来，幼虫的发育和生长速度一直被认为受到幼虫营养的影响，最近关于浮游生物小规模斑块的数据强调了自然界中普遍存在的短期食物变异性。然而，以前对浮游生物中幼虫发育时食物变异性的影响进行量化的努力是有限的。相比之下，研究两栖动物和昆虫生命周期的生态学家建立了几个理论模型，并进行了全面的实验，以测试环境变化对变态时间和变态大小的影响。这项研究将应用从两栖动物和昆虫变态的生态学研究中获得的经验教训来测试海洋无脊椎动物发育过程中短期食物变异性的影响。将在不同的幼虫(多毛类、双壳类、甲壳类、棘皮类)上进行实验室实验，以测试在短期食物变异性背景下幼虫发育和生长的理论模型的定量预测。理论框架和经验数据将促进对食物变异性的影响的全面理解，然后可以将其纳入海洋扩散和补充的模型。除了在不同的喂养方式下测量变态的时间和大小外，还将测量已知的调节发育时间的microRNAs的时间表达，目的是获得新的工具来在现场分析幼虫。教育和推广将明确地整合到研究计划中，让本科生团队进行许多实验，作为为期一年的顶峰课程(《高级研究经验：海洋无脊椎动物幼虫》)的一部分，并开发一个由高中教师和他们的学生参与的同行指导计划(学习：幼虫生态学和研究网络)。在Capstone课程的第一学期，本科生将学习无脊椎动物幼虫形态的多样性，实践幼虫的培养技术，并制定专注于感兴趣的物种的个人研究方案。学生将审阅同龄人撰写的建议书，并在小组审阅的环境中对建议书进行评估。在第二学期，四名学生组成的小组将合作将提案修改为小组项目，然后进行实验。大多数幼虫饲养实验在技术上并不困难，但它们是非常劳动密集型的。在合作团队中工作和学习将分配工作量，丰富教育体验。本科生团队将在研究过程中编辑视频日记，并将以四种形式展示他们的项目：科学论文、口头陈述、海报和作为学习计划的一部分在高中生物课上的陈述。学习将是一个由PI和他的本科生与高中生物老师和他们的学生合作的项目。该计划将针对市中心和种族多元化的高中。该计划的核心内容将包括高中生物课，对幼虫周期仅持续几天的耐寒甲壳类动物进行幼虫喂养实验。这些简单的实验将与高年级本科生进行的更复杂的实验平行进行，创造一个共同的主题，促进高中生和大学生之间的讨论和同行指导。该项目的设计将在每年由PI和高中教师参加的研讨会上得到改进，另外的研讨会将帮助本科生指导高中生。此外，学习计划将包括高中教师和学生作为暑期实习生参加PI的研究实验室的机会。

Most bottom-dwelling invertebrate animals have complex life cycles that include pelagic larvae. Many of these larvae feed in the plankton as they develop, grow, and disperse to habitats where they settle and metamorphose to benthic juveniles. The duration of the larval period is central to any model of transport and recruitment. Similarly, the size at metamorphosis can contribute to the success of newly settled recruits. The rates of larval development and growth have long been known to be influenced by larval nutrition, and recent data on small-scale patchiness in the plankton underscore the prevalence of short-term food variability in nature. Previous efforts to quantify the effects of food variability as larvae develop in the plankton have, however, been limited. In contrast, ecologists studying the life cycles of amphibians and insects have created several theoretical models and performed comprehensive experiments to test the effects of environmental variability on the timing of and size at metamorphosis. This study will apply lessons learned from ecological studies of amphibian and insect metamorphosis to test the effects of short-term food variability during the development of marine invertebrates. Lab experiments will be performed on diverse larvae (polychaetes, bivalves, crustaceans, echinoderms) to test the quantitative predictions of a theoretical model of larval development and growth in the context of short-term food variability. The theoretical framework and empirical data will foster a comprehensive understanding of the effects of food variability, which then can be incorporated into oceanographic models of dispersal and recruitment. In addition to measuring the timing of and size at metamorphosis in variable feeding regimes, the temporal expression of microRNAs that are known to regulate the timing of development also will be measured, with the aim of acquiring new tools to assay larvae in situ.Education and outreach will be integrated explicitly into the research program by having teams of undergraduate students perform many of the experiments as part of a year-long capstone course ("Senior Research Experience: Marine Invertebrate Larvae") and by developing a peer-mentoring program involving high-school teachers and their students (LEARN: Larval Ecology And Research Networking). In the first semester of the capstone course, undergraduates will learn the diversity of invertebrate larval forms, practice techniques for culturing larvae, and develop individual research proposals focused on a species of interest. Students will review proposals written by their peers and evaluate the proposals in a panel-review setting. In the second semester, teams of four students will collaborate to revise the proposals into group projects and then perform the experiments. Most larval-feeding experiments are not technically difficult, but they are very labor intensive. Working and learning in cooperative teams will distribute the workload and enrich the educational experience. Undergraduate teams will compile video journals during their research and will present their projects in four formats: a scientific paper, an oral presentation,a poster, and a presentation to a high-school biology class as part of the LEARN program. LEARN will be a program involving the PI and his undergraduate students collaborating with high-school biology teachers and their students. The program will target inner-city and ethnically diverse high schools. The program's centerpiece will encompass high-school biology classes performing larval feedingexperiments on hardy crustaceans that have larval periods lasting just a few days. These simple experiments will parallel the more elaborate ones performed by the senior undergraduates, creating a common theme to facilitate discussion and peer mentoring between the high-school and college students. The program's design will be refined each year during workshops involving thePI and the high-school teachers, and additional workshops will aid the undergraduates in mentoring the high-school students. Furthermore, the LEARN program will include opportunities for the high-school teachers and students to participate as summer interns in the PI's research lab.