Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Am Nat. 2010 Dec;176(6):830-4. doi: 10.1086/657041. Epub 2010 Oct 15.
Batesian mimicry is often imprecise. An underexplored explanation for imperfect mimicry is that predators might not be able to use all dimensions of prey phenotype to distinguish mimics from models and thus permit imperfect mimicry to persist. We conducted a field experiment to test whether or not predators can distinguish deadly coral snakes (Micrurus fulvius) from nonvenomous scarlet kingsnakes (Lampropeltis elapsoides). Although the two species closely resemble one another, the order of colored rings that encircle their bodies differs. Despite this imprecise mimicry, we found that L. elapsoides that match coral snakes in other respects are not under selection to match the ring order of their model. We suggest that L. elapsoides have evolved only those signals necessary to deceive predators. Generally, imperfect mimicry might suffice if it exploits limitations in predator cognitive abilities.
贝氏拟态常常不够精确。对于不完善的拟态，一个尚未被充分探讨的解释是，捕食者可能无法利用猎物表型的所有维度来区分拟态和模型，从而允许不完善的拟态持续存在。我们进行了一项野外实验，以测试捕食者是否能够区分致命的珊瑚蛇（Micrurus fulvius）和无毒的猩红王蛇（Lampropeltis elapsoides）。尽管这两个物种非常相似，但它们身体环绕的彩色环的顺序不同。尽管存在这种不精确的拟态，但我们发现，在其他方面与珊瑚蛇匹配的 L. elapsoides 并没有受到选择来匹配其模型的环序。我们认为，L. elapsoides 只进化出了那些必要的信号来欺骗捕食者。一般来说，如果不完善的拟态利用了捕食者认知能力的局限性，那么它可能就足够了。
