2009年10月8日 星期四

警戒性與貝氏擬態是否一定需要醒目顏色配合? 研究顯示歐洲蝮蛇的隱匿但具辯識性的斑紋可避免掠食者的攻擊

文獻來源: WüSTER W, ALLUM CSE, BIRTA BJARGARDOTTIR I, BAILEY KL, DAWSON KJ, GUENIOUI J, LEWIS J, MCGURK J, MOORE AG, NISKANEN M, POLLARD CP. 2004. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings. Proceedings of the Royal Society of London. Biological sciences 271(1556): 2495-2499. [全文下載]

Abstract
Predator avoidance of noxious prey, aposematism and defensive mimicry are normally associated with bright, contrasting patterns and colours. However, noxious prey may be unable to evolve conspicuous coloration because of other selective constraints, such as the need to be inconspicuous to their own prey or to specialist predators. Many venomous snakes, particularly most vipers, display patterns that are apparently cryptic, but nevertheless highly characteristic, and appear to be mimicked by other, non-venomous snakes. However, predator avoidance of viper patterns has never been demonstrated experimentally. Here, the analysis of 813 avian attacks on 12 636 Plasticine snake models in the field shows that models bearing the characteristic zigzag band of the adder (Vipera berus) are attacked significantly less frequently than plain models. This suggests that predator avoidance of inconspicuously but characteristically patterned noxious prey is possible. Our findings emphasize the importance of mimicry in the ecological and morphological diversification of advanced snakes.

圖片連結: wikipedia (photo credit: Marek Szczepanek)