Magnetic information calibrates celestial cues during migration
Magnetic information calibrates celestial cues during migration
复制标题
磁信息校准迁移过程中的天体线索
作者：
R. Sandberg;J. Bäckman;F. Moore;M. Lõhmus
候鸟利用天体和地磁方向信息来确定繁殖地和越冬地之间的路线。涉及这两个方向提示系统的提示冲突实验表明，方向信息可以通过校准从一个系统转移到另一个系统。我们设计了四种北美鸣禽的实验，目的是：（1）检查这些物种是否校准从一个系统到另一个系统的方向信息； (2) 确定校准中是否存在物种特异性差异。在秋季迁徙期间，用两种不同的技术记录迁徙方向：笼子测试和自由飞行释放测试。黄昏时在当地地磁场中进行的笼子测试揭示了物种特异性差异：红眼绿鹀（Vireo olivaceus）和北水鸫（Seiurus noveboracensis）选择了适合季节的南向，而靛蓝鹀（Passerinayanea）和灰猫鸟（Dumetella carolinensis）则朝向日落方向。当在偏转磁场中进行测试时，绿鹃和水鸫的反应是根据磁场的偏转改变方向，但鹀和猫鸫没有对治疗表现出任何反应。在释放测试中，所有四个物种都表明它们已经根据刚刚在笼子测试中经历的磁场重新校准了它们的恒星罗盘。由于释放测试是在当地地磁场中进行的，因此很明显，一旦确定了迁徙方向（很可能是在黄昏期间），鸟类就会在出发时使用重新校准的星罗盘来确定方向。版权所有 2000 动物行为研究协会。
Migratory birds use celestial and geomagnetic directional information to orient on their way between breeding and wintering areas. Cue-conflict experiments involving these two orientation cue systems have shown that directional information can be transferred from one system to the other by calibration. We designed experiments with four species of North American songbirds to: (1) examine whether these species calibrate orientation information from one system to the other; and (2) determine whether there are species-specific differences in calibration. Migratory orientation was recorded with two different techniques, cage tests and free-flight release tests, during autumn migration. Cage tests at dusk in the local geomagnetic field revealed species-specific differences: red-eyed vireo, Vireo olivaceus, and northern waterthrush, Seiurus noveboracensis, selected seasonally appropriate southerly directions whereas indigo bunting, Passerina cyanea, and grey catbird, Dumetella carolinensis, oriented towards the sunset direction. When tested in deflected magnetic fields, vireos and waterthrushes responded by shifting their orientation according to the deflection of the magnetic field, but buntings and catbirds failed to show any response to the treatment. In release tests, all four species showed that they had recalibrated their star compass on the basis of the magnetic field they had just experienced in the cage tests. Since release tests were done in the local geomagnetic field it seems clear that once the migratory direction is determined, most likely during the twilight period, the birds use their recalibrated star compass for orientation at departure. Copyright 2000 The Association for the Study of Animal Behaviour.