NSF Postdoctoral Fellowship in Biology: Ordered Evolution and Muscle-Specific Specializations of Constriction Behaviors in Snakes

该行动资助了2022财年的NSF生物学博士后研究奖学金，即调查基因组，环境和表型之间相互作用的生命规则的综合研究。该研究金支持研究员的研究和培训，以创新的方式为生活规则领域做出贡献。蛇的收缩一直被认为是一个重要的特征，帮助蛇变得非常多样化和广泛。这种行为相当复杂，可能是从简单的版本进化而来的，蛇会与猎物搏斗，而不是盘绕。研究员将研究这种有序的进化是如何发生的，创造一个新的框架来理解复杂的特征是如何在自然界中进化的。这种多方面的方法将涉及在蛇的家谱上绘制不同的“收缩”形式，研究它们肌肉的专门化，并调查这些特征是如何遗传调节的。此外，作为第一代低收入家庭的学生，研究员将把他所经历的机会传递给来自一所高中的学生，那里90%的学生来自代表性不足的群体，参与行为观察和蛇的实际实验。当祖先的特征变得复杂时，新特征往往会出现。然而，反复“构建”这些精细性状的机制，表型多样性的基本方面，仍然不清楚。蛇的“收缩”说明了生理和分子系统如何相互作用以维持生命。“收缩”描述了层次复杂的模式，包括（1）完全环线圈收缩;（2）部分环绕发夹环;和（3）简单的pinioning，类似于摔跤。这些并不是相互排斥的，更复杂的形式具有更高的性能，尽管缺乏肌肉质量或横截面积（力的两个相关因素）的增加。这表明“收缩”是通过一个有序的过程进化而来的，并涉及肌肉专业化以产生复杂性。本计画将利用系统发育比较的方法对蛇的收缩行为进行分类，以确定是否发生了有序的进化。研究员将进行肌肉实验，以确定复杂的收缩肌是否具有专门用于产生力量或抗疲劳的肌肉。这项工作还将确定与以前实验中测量的变化相关的每种“收缩”形式之间的遗传差异。该研究员将获得系统发育比较方法，行为生理学和转录组学的经验，以加强他未来的研究计划，并探索是什么使蛇如此成功。作为该项目的一部分，该研究员将从当地一所高中的弱势群体中招募感兴趣的学生，帮助他们进行实验，提高他们将自己视为未来STEM研究人员的能力。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the Fellow that will contribute to the area of Rules of Life in innovative ways. Constriction in snakes has been long thought to have been an important trait that helped snakes become extremely diverse and widespread. This behavior is quite complex and likely evolved from simpler versions where the snake wrestles its prey instead of coiling. The Fellow will study how this ordered evolution occurred, creating a new framework to understand how complex traits evolve in nature. This multifaceted approach will involve mapping different ‘constriction’ forms on the snake family tree, studying specializations of their muscles, and investigating how these traits are genetically regulated. Moreover, as a first-generation, low-income student, the Fellow will pay forward opportunities he experienced by involving students from a high school, where 90% of the students are from underrepresented groups, in behavioral observations and hands-on experiments with snakes.Novel traits often emerge when ancestral traits gain complexity. However, the mechanisms that iteratively “build” these elaborate traits, fundamental aspects of phenotypic diversity, remain unclear. ‘Constriction’ in snakes exemplifies how physiological and molecular systems intertwine to sustain life. ‘Constriction’ describes hierarchically complex patterns that include (1) fully looping coil constriction; (2) partially encircling hairpin looping; and (3) simple pinioning, similar to wrestling. These are not mutually exclusive, and more complex forms have increased performance despite lacking increases in muscle mass or cross-sectional area (two correlates of force). This suggests ‘constriction’ evolved through an ordered process and involved muscle specialization to produce complexity. This project will categorize constriction behaviors within snakes using phylogenetic comparative methods in order to determine whether ordered evolution occurred. The Fellow will conduct muscle experiments to determine whether complex constrictors have muscles specialized for force production or fatigue resistance. This work will also identify genetic differences between each ‘constriction’ form associated with the variation measured in the former experiments. The Fellow will gain experience with phylogenetic comparative methods, behavioral physiology, and transcriptomics to enhance his future research program and probe what makes snakes so successful. As part of this project, the Fellow will recruit interested students from underrepresented groups at a local high school to assist with experiments that enhance their ability to see themselves as future STEM researchers.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.