Kikuchi David W, Seymoure Brett M, Pfennig David W
Department of Biology, University of North Carolina, Chapel Hill, NC, USA.
Evol Dev. 2014 Mar;16(2):61-7. doi: 10.1111/ede.12064.
Mimicry, where one species resembles another species because of the selective benefits of sharing a common signal, is especially common in snakes. Snakes might be particularly prone to evolving mimicry if all species share some of the same proximate mechanisms that can be used to produce aposematic/mimetic signals. We evaluated this possibility by examining color pigments in 11 species of snakes from four different families, three species of which participate in a coral snake mimicry complex involving convergence in coloration. We found that all 11 species used combinations of two pteridine pigments and melanin in their coloration, regardless of whether or not they were mimics. Furthermore, the presence or absence of red pteridines was strongly correlated with the relative excitation of medium- and long-wavelength photoreceptors in birds, thereby linking shared pigmentation to perception of those pigments by likely agents of selection. Thus, precise color mimicry might be relatively easy to evolve among snakes owing to symplesiomorphies in pigmentation.
拟态是指一个物种因为共享一个共同信号所带来的选择优势而与另一个物种相似，这种现象在蛇类中尤为常见。如果所有物种都共享一些可用于产生警戒色/拟态信号的相同近因机制，那么蛇类可能特别容易进化出拟态。我们通过研究来自四个不同科的11种蛇的色素来评估这种可能性，其中三种蛇参与了一个涉及颜色趋同的珊瑚蛇拟态复合体。我们发现，所有11种蛇在其体色中都使用了两种蝶啶色素和黑色素的组合，无论它们是否为拟态物种。此外，红色蝶啶的有无与鸟类中长波和中波感光器的相对激发密切相关，从而将共享色素与可能的选择因子对这些色素的感知联系起来。因此，由于色素沉着方面的同形性状，精确的颜色拟态在蛇类中可能相对容易进化。
