Data from: Locomotor mode and the evolution of the hindlimb in Western Mediterranean Anurans

The evolutionary association between morphology, locomotor performance and habitat use is a central element of the ecomorphological paradigm, and it is known to underlie the evolution of phenotypic diversity in numerous animal taxa. In anuran amphibians the hindlimb acts as the propulsive agent, and as such, it is directly associated with jumping performance. In this study we combine individual- and species-level analyses to examine the effects of locomotor mode on body size and hindlimb morphology of Western Mediterranean anurans. In addition to the commonly studied hindlimb traits, we also examine the ratio between tibiofibula and femur length. Body size shows no signs of an evolutionary association to locomotor mode. Instead, hindlimb traits are significantly differentiated between locomotor groups, both at the individual and species levels. Specifically, we observe a gradient of tibiofibula to femur ratio values that matches biomechanical predictions. The analysis of adult static allometries indicates that these differences arise early in ontogeny. By comparing the fit of distinct evolutionary models we provide evidence that the locomotor mode adopted by each species to match the requirements of the habitat it frequents has shaped the evolution of the hindlimb, but not body size.

形态特征、运动性能与生境利用之间的演化关联是生态形态学范式（ecomorphological paradigm）的核心内容，且已知其支撑着众多动物类群的表型多样性演化。对于无尾两栖类（anuran amphibians）而言，后肢是其运动的推进器官，因此直接与跳跃性能相关联。本研究整合个体水平与物种水平的分析方法，探究运动模式对西地中海无尾类体型与后肢形态的影响。除了常规研究的后肢性状外，本研究还分析了胫腓骨（tibiofibula）与股骨（femur）的长度比值。研究结果显示，体型并未表现出与运动模式存在演化关联的迹象。相反，无论是个体水平还是物种水平，不同运动类群的后肢性状均存在显著分化。具体而言，我们观察到胫腓骨-股骨长度比值的变化梯度符合生物力学（biomechanical）的预测结果。对成体静态异速生长（static allometries）的分析表明，这类形态差异在个体发育早期就已形成。通过比较不同演化模型的拟合效果，本研究证实：各物种为适配其栖息生境需求而采用的运动模式，塑造了其后肢的演化，但并未对体型产生影响。