Repeated evolution of eye regression and loss: phylogenomics of scallops and relatives (Bivalvia: Pectinoidea)

在动物身上，眼睛的许多不同形式已经进化了无数次。然而，眼睛的生产、使用和维护在能量上是昂贵的。因此，生活在昏暗光线环境中的动物往往会有一双眼睛，以牺牲产生清晰图像为代价，最大限度地提高捕捉光线的能力。因此，不同的光环境产生的选择性压力预计会影响眼睛的数量、形状和性能。该项目将测试过渡到昏暗或完全黑暗的海洋环境可能与眼睛退化和丧失有关的假设。为了解决感官生物学中的这些基本问题，该项目将在进化框架下收集和分析遗传、形态和生态数据。更广泛的社会影响包括通过将分子概念纳入进化论教学中，同时将眼睛作为一个平易近人的例子，实现下一代科学标准（NGSS）的目标。通过与两位致力于该研究项目的教育工作者的合作，将创建高中水平的新进化论课程。课程计划将通过网站（如国家科学教学协会）公开，教学数据将发表在同行评议的期刊上。为了扩大培训机会，该小组将为另外12名高中三年级教师开设一个关于进化论教学的讲习班。工作坊的影响将通过前后调查来评估。这项工作还将直接支持博士后研究人员和本科生的跨学科培养。让代表性不足的群体参与STEM是一个优先事项。理解视觉系统的多样性需要确定负责功能和形态变化的生态和进化机制。扇贝及其亲戚（扇贝科）在单个动物身上有数十至数百只眼睛，并且在分类和生态形态学上具有广泛的等深线分布。拟议的工作将使用Pectinoidea来了解与可能导致眼睛退化和丧失的功能和生态变化相关的眼睛进化，例如海洋深度。利用果胶纲在宏观进化研究中的真正潜力，取决于对这一研究较少的分类群的可靠的、经过时间校准的系统发育和解剖学知识的解决。这项工作将解决三个核心问题：1)在深栖和浅栖物种中眼睛的形态和功能变化是什么？2)眼在什么时候、多少次退化或完全消失？3)暗光区或失光区的侵入是否与视力退化和丧失有关？该项目将使用锚定杂交富集方法推断果胶idea的系统基因组学，以了解眼睛进化和回归的速度和模式。该项目将1)提供扩展的分类群采样、时间校准的系统发育和分类修订；2)解决导致视觉系统进化和多样化的因素和力量知识方面的主要差距；3)对新特征背后的进化过程有更广泛的理解；4)为双壳类（一个未被充分研究但表型多样化的群体）创造新的遗传资源。所有材料将通过可公开访问的存储库存档。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Eyes in their many different forms have evolved numerous times in animals. However, eyes are energetically expensive to produce, use, and maintain. As a result, animals that live in dim light environments tend to have eyes that maximize the ability to capture light at the expense of generating clear images. Thus, different light environments produce selective pressures that are predicted to affect eye number, form, and performance. The project will test hypotheses of how the transition into dim or totally dark marine environments may be related to eye regression and loss. To address these fundamental questions in sensory biology, the project will collect and analyze genetic, morphological, and ecological data under an evolutionary framework. Broader societal impacts include addressing goals of the Next Generation Science Standards (NGSS) by incorporating molecular concepts in the teaching of evolution while using the eye as an approachable example. Novel curriculum on evolution at the high school level will be created through a collaboration with two educators immersed in the research project. Lesson plans will be publicly available via websites (e.g., National Science Teaching Association) and pedagogical data will be published in peer-reviewed journals. To expand training opportunities, the team will develop a workshop on teaching evolution for 12 additional high school teachers in Year 3. Workshop impact will be assessed with pre- to post- surveys. The work also will directly support the cross disciplinary training of postdoctoral researchers and undergraduate students. Participation of underrepresented groups in STEM is a priority.Understanding visual system diversity requires determining ecological and evolutionary mechanisms responsible for functional and morphological changes. Scallops and relatives (Pectinoidea) have tens to hundreds of eyes on a single animal and broad bathymetric distributions spanning the taxonomic and ecomorphological diversity of the clade. The proposed work will use the Pectinoidea to understand eye evolution in association with functional and ecological changes that may drive eye regression and loss, such as oceanic depth. Harnessing the true potential of pectinoideans for macroevolutionary research is contingent on the resolution of a robust time-calibrated phylogeny and anatomical knowledge for the poorly studied taxa. This work will address three central questions: 1) What are morphological and functional changes of eyes among deep- and shallow- dwelling species? 2) When and how many times have eyes been regressed or completely lost among pectinoidean taxa? 3) Could the invasion of dim light or aphotic zones be related to eye regression and loss? The project will infer the phylogenomics of Pectinoidea using an anchored hybrid enrichment approach to understand the tempo and mode of eye evolution and regression. The project will 1) provide extended taxon sampling, a time-calibrated phylogeny, and taxonomic revision; 2) address major gaps in knowledge of the factors and forces that have contributed to the evolution and diversification of visual systems; 3) inform a broader understanding of evolutionary processes underlying new traits; and 4) generate new genetic resources for bivalves, an understudied, but phenotypically diverse, group. All materials will be archived through publicly accessible repositories.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.