Collaborative Research: Phenotypic and lineage diversification after key innovation(s): multiple evolutionary pathways to air-breathing in labyrinth fishes and their allies

某些解剖结构或行为可能会在进化规模上改变某些有机体的游戏规则。这些被称为“关键创新”的特征从根本上改变了有机体与环境的互动方式，并可能带来竞争优势。例如，创新能够避免与其他物种的竞争或捕食，或者允许获得新的栖息地和资源。对于一些鱼类来说，一项潜在的关键创新是能够用独特的呼吸器官呼吸大气中的空气。这些呼吸空气的器官在斗鱼、蛇头和蛇头等鱼类中进化了几次，可能是它们在数百万年前成功传播到世界各地的关键，也可能是它们在最近的生物入侵(例如蛇头)期间再次传播的关键。这个项目将研究呼吸空气的结构是否是关键的创新，然后回答这些结构如何改变内在的(解剖学)或外部的(生态)进化动态。这个项目将使用高分辨率的微型计算机断层成像(MicroCT)，结合对比染色和组织学，提供对Anabantaria(金枪鱼、乌贼、刺鳗和沼泽鳗)呼吸空气器官的多样性的洞察。利用系统发育比较框架，研究小组将评估不同呼吸空气结构在脊椎动物之间的同源性。三维几何形态测量学将被用来捕捉这些鱼类的头骨形状多样性，无论是呼吸空气的还是非呼吸空气的物种。最后，研究小组将测试呼吸空气的结构是否是关键的创新，然后回答这些结构如何改变进化动力学，要么是通过(1)为大陆入侵提供新的机会，(2)促进身体形状多样化，要么(3)通过改变头骨(呼吸空气器官所在的头骨)如何适应变化的角色的基本原理。对于这项研究的更广泛影响，路易斯维尔大学的研究团队将与密歇根大学自然历史博物馆的同事合作，进行外联和培训。路易斯维尔大学研究团队、PI、博士后和学生将与路易斯维尔动物园社区项目办公室合作，在旨在提高儿童对动物和彼此的共鸣的现有项目的基础上再接再厉。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。

Some anatomical structures or behaviors can be game-changing at evolutionary scales for certain groups of organisms. Such traits, called “key innovations”, radically alter how an organism interacts with its environment, and may confer competitive advantages. Examples are innovations that enable avoiding competition or predation with other species, or allowing access to new habitats and resources. A potential key innovation for some fishes is the ability to breathe atmospheric air with a unique air-breathing organ. These air-breathing organs have evolved several times in fishes such as bettas, gouramis, and snakeheads, and may have been the key to their success in spreading across the world millions of years ago and again during more recent biological invasions (e.g., snakeheads). This project will examine whether air-breathing structures are key innovations and then answer how these structures alter intrinsic (anatomical) or extrinsic (ecological) evolutionary dynamics.This project will use high resolution micro-computed tomographic imaging (microCT), coupled with contrast-staining and histology to provide insight into the diversity of air-breathing organs across the Anabantaria (gouramis, snakeheads, spiny and swamp eels). Using a phylogenetic comparative framework, the research team will assess the homology of different air-breathing structures across anabantarians. Three-D geometric morphometrics will be used to capture skull shape diversity in these fishes, air-breathing and non-air-breathing species alike. Finally, the research team will test whether air-breathing structures are key innovations and then answer how these structures alter evolutionary dynamics, either by (1) providing new opportunities for continental invasions, (2) facilitating body shape diversification, or (3) by changing the fundamentals of how the skull, which houses the air-breathing organ, adapts to changing roles. For the Broader Impacts of this study, the research team at University of Louisville will partner with colleagues at the University of Michigan Museum of Natural History for outreach and training. The University of Louisville research team, PI, post docs and students, will partner with the Louisville Zoo community programs office to build on existing programs aimed at increasing children’s empathy towards animals and each other.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.