NSF Postdoctoral Fellowship in Biology FY 2017: Evolutionary morphology and cranial constraints in piranhas, pacus, and their allies

这项行动资助了2017财年的NSF生物学博士后研究奖学金，扩大了生物学中代表性不足的群体的参与。该奖学金支持研究员以创新方式利用生物收藏的研究和培训。食人鱼和他们的盟友数量近100个物种，尽管看似简单的下巴，这些鱼吃的猎物从整个鱼到坚果，水果和树叶等植物物质。研究人员可以通过研究捕食者及其猎物的历史来了解生物材料和结构如何以及为什么发生变化，并注意哪些行为，结构和材料保持同步进化（进化趋同）。理解解剖学如何进化的第一步是建立一个活的食人鱼、帕库及其亲属的进化谱系（epigeny），作为一个框架。该项目将研究食人鱼及其盟友的摄食解剖结构是如何构建的，这些结构在捕食不同猎物时如何表现，并在这些鱼类的进化历史中绘制这些特征。该研究员将使用靶向外显子捕获方法构建一个尖端的锯脂鲤基因组树。这些进化关系将被用来作为一个框架，了解喂养性状的演变，可视化通过碘增强对比染色结合显微计算机断层扫描（micro-CT）。 该研究员将使用FEA（有限元分析）等生物力学建模方法来研究不同的头骨形状如何在喂食过程中抵抗应力，并通过分析肌肉形态和从微CT成像测量的颌杠杆动力学来量化喂食性能。该项目提出，食人鱼的头骨将显示出颅结构强度，牙齿形状和进食性能之间的进化权衡。这些特征的某些组合也将与特定的饮食相关，如吃鳞片，吃水果和食鱼等。这个项目利用博物馆的分子收藏品来进一步了解像食人鱼这样有魅力的鱼类的进化关系。博物馆标本的形态成像将生成一个用于教学和推广方法的食人鱼CT模型数据库，任何人都可以免费下载和3D打印。培训目标包括研究员获得一些最先进的技术，用于可视化解剖和建模这些结构的材料和建筑行为的经验。更广泛的影响包括针对有语言障碍的大学生和大学预科生的教育推广，使这些学生对科学感兴趣，并加强他们进入学术界和其他研究型职业的信心和能力。 这些研究的结果也将发表在同行评审的期刊上，并在科学会议上分享。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2017, Broadening Participation of Groups Under-represented in Biology. The fellowship supports research and training of the fellow utilizing biological collections in innovative ways. Piranhas and their allies number almost 100 species and despite deceptively simple jaws, these fishes consume prey ranging from whole fishes to plant matter like nuts, fruits, and leaves. Researchers can understand how and why biomaterials and structures have changed by studying the history of predators and their prey, and noting which behaviors, structures, and materials keep evolving in tandem (evolutionary convergence). The first step in understanding how anatomy has evolved is building an evolutionary genealogy (phylogeny) of living piranhas, pacu, and their relatives to use as a framework. This project will then examine how the feeding anatomy of piranhas and their allies is constructed, how these structures perform when feeding on different prey, and map these traits across the evolutionary history of these fishes.The fellow will construct a cutting-edge phylogenomic tree for serrasalmid fishes using targeted exon capture methods. These evolutionary relationships will be used as a framework for understanding feeding trait evolution, visualized through iodine-enhanced contrast staining coupled with micro-computed tomography (micro-CT). The fellow will use biomechanical modeling methods like FEA (finite-element analysis) to examine how different skull shapes resist stresses during feeding, and quantify feeding performance by analyzing muscle morphology and jaw lever dynamics measured from micro-CT imaging. This project proposes that the skulls of piranhas will show evolutionary trade-offs among cranial architectural strength, tooth shape, and feeding performance. Certain combinations of these traits will also be correlated with specific diets like scale-eating, fruit-eating, and piscivory, among others. This project utilizes molecular collections from museums to further our understanding of the evolutionary relationships of charismatic fishes like piranhas. Morphological imaging of museum specimens will generate a database of piranha CT models for teaching and outreach methods, free for anyone to download and 3D print. Training goals include the fellow gaining experience in some of the most advanced techniques for visualizing anatomy and modeling the material and architectural behavior of these structures. Broader impacts include educational outreach targeting university and pre-university students with speech disabilities, engaging these student's interests in science, and reinforcing their confidence and ability for entering academia and other research-based professions. Results from the studies will also be published in peer-reviewed journals and shared at scientific meetings.