Lund Vision Group, Department of Biology, University of Lund, Sölvegatan 35, 22362 Lund, Sweden.
Department of Psychology, Queens University, 62 Arch Street, Kingston, ON K7L 3N6, Canada.
Curr Biol. 2018 Jul 9;28(13):2160-2166.e5. doi: 10.1016/j.cub.2018.05.030. Epub 2018 Jun 21.
Like many birds [1], numerous species of nocturnal moths undertake spectacular long-distance migrations at night [2]. Each spring, billions of Bogong moths (Agrotis infusa) escape hot conditions in different regions of southeast Australia by making a highly directed migration of over 1,000 km to a limited number of cool caves in the Australian Alps, historically used for aestivating over the summer [3, 4]. How moths determine the direction of inherited migratory trajectories at night and locate their destination (i.e., navigate) is currently unknown [5-7]. Here we show that Bogong moths can sense the Earth's magnetic field and use it in conjunction with visual landmarks to steer migratory flight behavior. By tethering migrating moths in an outdoor flight simulator [8], we found that their flight direction turned predictably when dominant visual landmarks and a natural Earth-strength magnetic field were turned together, but that the moths became disoriented within a few minutes when these cues were set in conflict. We thus conclude that Bogong moths, like nocturnally migrating birds [9], can use a magnetic sense. Our results represent the first reliable demonstration of the use of the Earth's magnetic field to steer flight behavior in a nocturnal migratory insect.
和许多鸟类一样，许多夜行动物在夜间进行壮观的长距离迁徙。每年春天，数以十亿计的博贡飞蛾（Agrotis infusa）为了逃避澳大利亚东南部不同地区的炎热气候，会进行高度定向的迁徙，飞行超过 1000 公里，前往澳大利亚阿尔卑斯山的少数几个凉爽洞穴，这些洞穴历史上被用于夏季休眠[3,4]。目前还不清楚飞蛾如何在夜间确定遗传迁徙轨迹的方向，并找到它们的目的地（即导航）[5-7]。在这里，我们表明博贡飞蛾能够感知地球磁场，并将其与视觉地标结合起来引导迁徙飞行行为。通过在户外飞行模拟器中系留迁徙中的飞蛾[8]，我们发现当主要的视觉地标和自然的地球强度磁场一起转动时，它们的飞行方向可以预测地改变，但当这些线索发生冲突时，飞蛾在几分钟内就会迷失方向。因此，我们得出结论，博贡飞蛾和夜间迁徙的鸟类一样[9]，可以利用磁场感来导航。我们的研究结果首次可靠地证明了利用地球磁场来引导夜间迁徙昆虫的飞行行为。
