Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, USA.
Integr Comp Biol. 2020 Jul 1;60(1):202-214. doi: 10.1093/icb/icaa011.
Specialist species often possess adaptations that strongly distinguish them from their relatives, obscuring the transitional steps leading to specialization. Sidewinding snakes represent an example of locomotor specialization in an elongate, limbless terrestrial vertebrate. We typically think of sidewinding as a gait that only a handful of very specialized snake species perform, mostly vipers from sandy desert environments. Some of these desert-dwelling vipers are so specialized that they only rarely use more common types of locomotion. However, some non-viper species sidewind facultatively in particular circumstances, and a few may regularly sidewind under natural conditions. Numerous accounts report facultative sidewinding in species that more typically perform other types of locomotion. I have compiled these accounts, uncovering evidence that dozens of species perform sidewinding with varying proficiency under a variety of conditions. These facultative sidewinders can reveal insight into the evolution and biomechanics of sidewinding, and they provide ample opportunities for future study.
特化物种通常具有使其与其亲缘物种明显区分的适应性，从而掩盖了导致特化的过渡步骤。侧身蛇是一种在细长、无肢的陆地脊椎动物中出现的运动特化的例子。我们通常认为侧身蜿蜒是一种步态，只有少数非常特化的蛇种会采用，主要是来自沙质沙漠环境的蝰蛇。这些生活在沙漠中的蝰蛇中有一些非常特化，以至于它们很少使用更常见的运动方式。然而，一些非蝰蛇物种在特定情况下会偶然侧身蜿蜒，而少数物种在自然条件下可能会经常侧身蜿蜒。许多报道都报告了一些物种在其他类型的运动中具有特化的侧身蜿蜒能力。我已经收集了这些报告，发现了证据表明，在各种条件下，数十种物种以不同的熟练程度进行侧身蜿蜒。这些偶然侧身蜿蜒的动物可以揭示侧身蜿蜒的进化和生物力学方面的见解，并且为未来的研究提供了充分的机会。
