Collaborative Research: Testing hypotheses about diversity, gene flow, and effective population size in marine planktonic ciliates

环境微生物学的分子方法和经典方法的分离并没有取得成果，这是该领域在未来几年面临的最重要的挑战之一。经典的方法以数百年的传统为中心，通过细致的观察和分析来描述单个物种，以生成专著，就像对植物和动物所做的那样。不幸的是，对新分子技术的匆忙有时会忽视这一传统，关于新的谱系的说法前所未见，以及基于环境DNA样本的微生物真核生物惊人多样性的报道，甚至连最基本的显微镜观察都没有支持。面对传统和分子之间的这种脱节，该项目是研究海洋纤毛虫多样性和基因流动的两种方法的结合。初步数据显示，在浮游纤毛虫的一些分支中，确实存在着相对较少的形态种下的高水平的分子多样性。在其他支系(一些编舞)中，相反的情况似乎是真的，基于分子数据，形态异质性被明显的克隆线所支撑。目前，我们不了解是什么维持了一些支系的多样性；我们也不知道为什么其他支系表现出低多样性。这个问题既适用于实验方法，也适用于观察方法。这个项目将采取双管齐下的方法，结合分子(克隆文库、DGGE、FISH)和传统(光学显微镜)技术来解决三个广泛的问题：1)。影响浮游海洋纤毛虫分布和多样性的最重要的物理和生物因素是什么？海洋纤毛虫种群的有效种群数量是多少，这与普查种群数量相比如何？与分子描述相比，传统的纤毛虫物种形态描述效果如何？使用分子和显微镜相结合的方法，研究人员将在沿海浮游纤毛虫中解决这些问题。对结果数据的分析将使人们深入了解北大西洋纤毛虫物种的性质和基因流动的模式。这项提议的更广泛影响包括培训和接触K-12教育工作者。私人投资机构过去的记录表明，他们在培训本科生和研究生方面都取得了成功。这两家私人投资机构在指导来自传统代表人数不足的群体的学生方面都有良好的记录，他们将继续以扩大这一项目参与者多样性的招聘活动为目标。PIS还将通过与位于康涅狄格州康涅狄格州的私人非营利性海洋教育组织Project Ocean建立伙伴关系，参与教师培训。每年夏天，他们将接待两名K-12教师，他们将获得学费奖学金，在私人投资促进机构的监督下，获得纤毛虫生物学和生态学研究经验的研究生学分。最后，该项目产生的数据将通过互联网和出版物提供。

The decoupling of molecular and classical approaches to environmental microbiology has not been fruitful and it represents one of the most important challenges for the field in the coming years. Classical approaches center on the centuries-old tradition of describing individual species via meticulous observation and analysis to generate monographs, such as is done for plants and animals. Unfortunately, the rush to new molecular techniques has sometimes ignored this tradition, with claims about new lineages never seen before and reports of staggering diversity of microbial eukaryotes based on environmental DNA samples not backed up by even the most elementary microscopic observations. In the face of this disconnect between the traditional and the molecular, this project is a marriage of the two approaches in the study of marine ciliate diversity and gene flow. Preliminary data show that in some clades of planktonic ciliates (Strombidiidae) there is indeed a high level of molecular diversity underlying a relatively small number of morphospecies. In other clades (some choreotrichs), the opposite appears to be true, with morphological heterogeneity underlain by apparently clonal lines, based on molecular data. Currently, we do not understand what sustains diversity in some clades; nor do we know why other clades show low diversity. This problem is amenable to both experimental and observational approaches. This project will follow a two-pronged approach, combining molecular (clone libraries, DGGE, FISH) and traditional (light microscopy) techniques to address three broad questions: 1). What are the most important physical and biological factors that affect distribution and diversity of planktonic marine ciliates? 2). What is the effective population size for marine ciliate populations, and how does this compare to census population sizes? 3). How well do traditional morphological descriptions of ciliate species fare when compared with molecular characterizations? Using a combination of molecular and microscopy methods, the investigators will address these questions in coastal planktonic ciliates. Analyses of the resulting data will yield insights into the nature of ciliate species and patterns of gene flow within the North Atlantic.The broader impacts of this proposal include training and outreach to K-12 educators. The PIs have a past record that demonstrates success in training both undergraduate and graduate students. Both PIs have proven track records in mentoring students from traditionally underrepresented groups, and they will continue to aim recruitment activities towards broadening diversity of participants in this project. The PIs will also participate in teacher training through a partnership with Project Oceanology, a private non-profit marine education organization located at UConn. Each summer of the project they will host two K-12 teachers who will receive tuition scholarships to earn graduate credit for research experiences in ciliate biology and ecology under the supervision of the PIs. Finally, resulting data from this project will be made available through the internet as well as in publications.