Life on a Limb: The Evolution of Locomotion in Arboreal Specialists

进化生物学的一个核心问题是形态、功能和栖息地的利用是如何进化的。树栖动物独立地进化出了许多非凡的运动适应能力，比如粘连的趾垫和可抓握的尾巴，使它们能够在复杂的栖息地中移动。然而，大多数关于运动的研究都是在近似陆地栖息地的条件下进行的，然而，由于树木栖息地的表面直径和陡峭的倾角不同，对动物的功能构成了独特的挑战。此外，没有研究调查动物如何根据表面直径和倾角来区分树木栖息地。pi将通过研究一组8种形态多样的树栖Anolis蜥蜴来解决这些问题，这些蜥蜴的进化关系已经得到了很好的理解。实验室研究将揭示表面直径和倾斜度对这些物种的运动模式（运动学）和肌肉活动模式（肌电图）的影响，而实地研究将解决这些物种使用特定表面直径和倾斜度的频率。这种综合方法将对适应的本质和环境变量如何影响运动产生重要的见解。

A central question in evolutionary biology is how morphology, function and habitat use have evolved. Arboreal animals have independently evolved many remarkable adapatations for locomotion, sucha as adhesive toepads and prehensile tails that enable them to move through their complex habitats. However, most studies of locomotion have taken place under conditions that approximate terrestrial habitats, yet arboreal habitats pose unique functional challenges for animals because of varying surface diameters and steep inclines. Futher, no studies have examined how animals segregate arboreal habitats based on surface diameters and inclines. The PIs will address these issues by examining a group of eight morphologically diverse arboreal Anolis lizard species whose evolutionary retationships are well-understood. Laboratory studies will reveal the effects of both surfac diameter and incline on the movement patterns (kinematics) and muscle activity patterns (EMGs) of these species, whereas field studies will address how often these species use particular surface diameters and inclines. This Integrative approach will yield important insights into the nature of adaptation and how environmental variables affect locomotion.