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

许多不同形式的眼睛在动物身上进化了无数次。然而，生产、使用和维护眼睛的能源成本很高。因此，生活在暗光环境中的动物往往有眼睛，最大限度地提高捕捉光线的能力，但代价是产生清晰的图像。因此，不同的光环境会产生选择性压力，预计会影响眼睛的数量、形状和表现。该项目将测试有关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。为了解决感觉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，同时将眼睛作为可接近的例子来解决下一代科学标准(NGSS)的目标。通过与两名沉浸在研究项目中的教育工作者合作，将在高中水平上创建关于进化的新课程。教学计划将通过网站(例如，国家科学教学协会)公开提供，教学数据将发表在同行评议的期刊上。为了扩大培训机会，该小组将在第三年为另外12名高中教师开发一个关于教学演变的工作坊。工作坊的影响将通过前后调查进行评估。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。代表不足的群体参与STEM是一个优先事项。理解视觉系统的多样性需要确定导致功能和形态变化的生态和进化机制。扇贝和近亲(扇贝总科)对一种动物有数十到数百只眼睛，水深分布广泛，分布在该分支的分类和生态地貌多样性上。这项拟议的工作将使用Pectinoidae来了解与功能和生态变化相关的眼睛进化，这些变化可能会导致眼睛退化和丧失，例如海洋深度。利用果胶动物的真正潜力进行宏观进化研究，取决于对研究较少的类群的强大的、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)深水和浅水物种之间眼睛的形态和功能变化是什么？2)在脊椎动物类群中，眼睛何时退化或完全丧失的？3)昏暗的光线或无光带的入侵是否与眼睛的退化和丧失有关？该项目将使用一种锚定的杂交丰富方法来推断Pectinoidae的系统发生学，以了解眼睛进化和回归的节奏和模式。该项目将1)提供扩展的分类样本、时间校准的系统发育和分类学修订；2)解决在促进视觉系统的进化和多样化的因素和力量方面的主要知识空白；3)使人们更广泛地了解潜在的新特征的进化过程；以及4)为双壳类产生新的遗传资源，双壳类是一个研究较少但表型多样的群体。所有材料都将通过公众可访问的资源库存档。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.