Data from: Linking locomotor performance to morphological shifts in urban lizards

Urban habitats are drastically modified from their natural state, creating unique challenges and selection pressures for organisms that reside in them. We compared locomotor performance of Anolis lizards from urban and forest habitats on tracks differing in angle and substrate, and found that using artificial substrates came at a cost: lizards ran substantially slower and frequently lost traction on man-made surfaces compared to bark. We found that various morphological traits were positively correlated with sprint speed and that these same traits were significantly larger in urban compared to forest lizards. We found that urban lizards ran faster on both man-made and natural surfaces, suggesting similar mechanisms improve locomotor performance on both classes of substrate. Thus, lizards in urban areas may be under selection to run faster on all flat surfaces, while forest lizards face competing demands of running, jumping, and clinging to narrow perches. Novel locomotor challenges posed by urban habitats likely have fitness consequences for lizards that cannot effectively use man-made surfaces, providing a mechanistic basis for observed phenotypic shifts in urban populations of this species.

城市生境相较于其自然原始状态已发生剧烈改造，为栖息其中的生物带来了独特的生存挑战与选择压力。我们针对来自城市与森林生境的安乐蜥（Anolis），在不同倾角和基质的实验跑道上开展了运动能力测试，结果发现使用人工基质存在适配代价：相较于树皮基质，安乐蜥在人工表面的奔跑速度显著更慢，且时常出现打滑失稳的情况。我们还发现，多项形态学特征与冲刺速度呈显著正相关，且城市种群安乐蜥的这些特征尺寸显著大于森林种群。此外我们观察到，城市种群安乐蜥在人工基质与天然基质表面的奔跑速度均更快，这提示存在相似的生理机制，可提升两类基质上的运动表现。由此可见，城市生境中的安乐蜥可能正承受着在所有平坦表面提升奔跑速度的选择压力，而森林种群则需兼顾奔跑、跳跃以及攀附狭窄栖木的多重生存需求。城市生境带来的全新运动挑战，可能对无法有效适配人工表面的安乐蜥产生适合度层面的影响，这也为该物种城市种群中已观测到的表型分化现象提供了机制层面的解释依据。