COLLABORATIVE RESEARCH: Natural Selection on Growth and Locomotor Development in Eastern Cottontail Rabbits (Sylvilagus floridanus)

生命的少年阶段可能特别危险。幼小的动物必须在与成年动物相同的环境中生存，尽管它们的体型较小，肌肉较弱，以及其他与生长有关的身体能力限制。因为，根据定义，幼崽还没有繁殖，我们应该期待强大的选择机制，可以潜在地抵消这些年龄相关的身体表现限制，使个体达到成年，繁殖，从而保持进化的适应性。拟议的研究将结合东部棉尾兔（Sylvilagus floridanus）的肌肉骨骼生长、身体表现和存活率的测量，以明确地测试有关哺乳动物生长和发育的适应性本质的大范围假设。东部棉尾虫在三周大的时候就能脱离母亲独立生活，在出生后的第一年里，它们会经历很高的捕食压力，这使它们成为解决这些问题的理想物种。本研究收集的基础数据将有助于更好地理解自然选择如何影响肌肉骨骼的生长和发育，以应对捕食，为进化过程本身提供新的见解。本研究分为三个具体目标。首先，研究人员将收集东部棉尾鱼肌肉骨骼生长的详细数据，包括肌肉和骨骼强度的详细数据。其次，研究人员将对幼兔和成年兔的身体运动能力（即加速和冲刺能力）进行定量测量。最后，无线电跟踪数据将与家境大小、栖息地质量和捕食风险等生态数据相结合，以经验方式记录幼兔的生存情况。这些数据将使研究人员能够全面检查肌肉骨骼解剖、身体表现和进化适应性之间的关系，以正式测试被认为有助于促进幼鱼生存的特征的适应性意义。该项目将在涉及的三个机构之间建立跨学科合作，帮助在俄亥俄州东北部建立一个研究和培训网络。资金还将为本科生提供学习活体生物力学和野外生态学方法的机会。这样的机会是难得的，也是学生重要的教育资源。在此项目中收集的骨骼材料将捐赠给当地的博物馆和学校，为公共教育和研究提供宝贵的工具。最后，在这项研究中产生的存活率估计可以用来为俄亥俄州自然资源部的政策决策提供信息，以便在整个俄亥俄州建立可接受的狩猎和诱捕数量。

The juvenile stage of life can be particularly perilous. Immature animals must survive in the same environments as adults despite smaller body size, weaker muscles and other growth-related limitations on physical ability. Because, by definition, juveniles have yet to reproduce, one should expect strong selection for mechanisms that could potentially offset these age-related limits on physical performance, allowing individuals to reach adulthood, reproduce, and thus maintain evolutionary fitness. The proposed research will combine measures of musculoskeletal growth, physical performance, and survivorship in eastern cottontail rabbits (Sylvilagus floridanus) to explicitly test broad-scale hypotheses about the adaptive nature of mammalian growth and development. Eastern cottontails are independent of their mothers by three weeks of age and experience high predation pressure during the first year of life, making them an ideal species in which to address these issues. The fundamental data collected in this study will provide a greater understanding of how natural selection operates on musculoskeletal growth and development in response to predation, providing novel insight into the process of evolution itself. This research is organized into three specific aims. First, researchers will collect detailed measures of musculoskeletal growth in eastern cottontails, including detailed data on muscle and bone strength. Second, the investigators will generate quantitative measures of physical performance ability (i.e., acceleration and sprinting capacities) in juvenile and adult rabbits. Finally, radio-tracking data will be combined with ecological data on home range size, habitat quality and predation risk to empirically document survivorship in juvenile rabbits. These data will allow the researchers to holistically examine associations among musculoskeletal anatomy, physical performance and evolutionary fitness, as required to formally test the adaptive significance of the traits thought to promote juvenile survival.This project will create interdisciplinary collaborations among the three institutions involved, helping to foster a network of research and training in northeastern Ohio. Funding will also provide opportunities for undergraduates to learn in vivo biomechanical and field ecology methods. Such opportunities are rare and constitute a major educational resource for students. Skeletal materials gathered during this project will be donated to local museums and schools, providing valuable public educational and research tools. Finally, the survivorship estimates generated during this research can be used to inform the policy decisions of the Ohio Department of Natural Resources in order to establish acceptable numbers for hunting and trapping throughout Ohio.