Barber Jesse R, Leavell Brian C, Keener Adam L, Breinholt Jesse W, Chadwell Brad A, McClure Christopher J W, Hill Geena M, Kawahara Akito Y
Department of Biological Sciences, Boise State University, Boise, ID 83725;
Florida Museum of Natural History, McGuire Center for Lepidoptera and Biodiversity, University of Florida, Gainesville, FL 32611;
Proc Natl Acad Sci U S A. 2015 Mar 3;112(9):2812-6. doi: 10.1073/pnas.1421926112. Epub 2015 Feb 17.
Adaptations to divert the attacks of visually guided predators have evolved repeatedly in animals. Using high-speed infrared videography, we show that luna moths (Actias luna) generate an acoustic diversion with spinning hindwing tails to deflect echolocating bat attacks away from their body and toward these nonessential appendages. We pit luna moths against big brown bats (Eptesicus fuscus) and demonstrate a survival advantage of ∼ 47% for moths with tails versus those that had their tails removed. The benefit of hindwing tails is equivalent to the advantage conferred to moths by bat-detecting ears. Moth tails lured bat attacks to these wing regions during 55% of interactions between bats and intact luna moths. We analyzed flight kinematics of moths with and without hindwing tails and suggest that tails have a minimal role in flight performance. Using a robust phylogeny, we find that long spatulate tails have independently evolved four times in saturniid moths, further supporting the selective advantage of this anti-bat strategy. Diversionary tactics are perhaps more common than appreciated in predator-prey interactions. Our finding suggests that focusing on the sensory ecologies of key predators will reveal such countermeasures in prey.
动物为转移视觉导向型捕食者的攻击而进化出的适应性特征已多次出现。通过高速红外摄像，我们发现月形天蚕蛾（Actias luna）利用旋转的后翅尾突产生声学干扰，将蝙蝠的回声定位攻击从其身体引向这些非必需的附属物。我们让月形天蚕蛾与大棕蝠（Eptesicus fuscus）对抗，结果表明，有尾突的蛾子比尾突被移除的蛾子的生存优势约为47%。后翅尾突的益处等同于蝙蝠探测耳朵赋予蛾子的优势。在蝙蝠与完整月形天蚕蛾的55%的互动中，蛾尾将蝙蝠的攻击吸引到了这些翅膀区域。我们分析了有无后翅尾突的蛾子的飞行运动学，发现尾突在飞行性能方面作用极小。利用一个可靠的系统发育树，我们发现长勺状尾突在天蚕蛾科蛾类中独立进化了四次，进一步支持了这种抗蝙蝠策略的选择优势。在捕食者与猎物的相互作用中，转移策略可能比我们意识到的更为常见。我们的发现表明，关注关键捕食者的感官生态学将揭示猎物的此类应对措施。
