BACKGROUND The Radical Pair model proposes that magnetoreception is a light-dependent process. Under low monochromatic light from the short-wavelength part of the visual spectrum, migratory birds show orientation in their migratory direction. Under monochromatic light of higher intensity, however, they showed unusual preferences for other directions or axial preferences. To determine whether or not these responses are still controlled by the respective light regimes, European robins, Erithacus rubecula, were tested under UV, Blue, Turquoise and Green light at increasing intensities, with orientation in migratory direction serving as a criterion whether or not magnetoreception works in the normal way. RESULTS The birds were well oriented in their seasonally appropriate migratory direction under 424 nm Blue, 502 nm Turquoise and 565 nm Green light of low intensity with a quantal flux of 8 x 10(15) quanta s(-1) m(-2), indicating unimpaired magnetoreception. Under 373 nm UV of the same quantal flux, they were not oriented in migratory direction, showing a preference for the east-west axis instead, but they were well oriented in migratory direction under UV of lower intensity. Intensities of above 36 x 10(15) quanta s(-1) m(-2) of Blue, Turquoise and Green light elicited a variety of responses: disorientation, headings along the east-west axis, headings along the north-south axis or 'fixed' direction tendencies. These responses changed as the intensity was increased from 36 x 10(15) quanta s(-1) m(-2) to 54 and 72 x 10(15) quanta s(-1) m(-2). CONCLUSION The specific manifestation of responses in directions other than the migratory direction clearly depends on the ambient light regime. This implies that even when the mechanisms normally providing magnetic compass information seem disrupted, processes that are activated by light still control the behavior. It suggests complex interactions between different types of receptors, magnetic and visual. The nature of the receptors involved and details of their connections are not yet known; however, a role of the color cones in the processes mediating magnetic input is suggested.

中文翻译：

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鸟类中与光有关的磁感受：单色光强度的增加改变了响应的性质。

背景技术自由基对模型提出，磁接收是一个与光有关的过程。在来自光谱的短波长部分的低单色光下，候鸟显示出其迁徙方向的方向。然而，在更高强度的单色光下，它们显示出对其他方向或轴向方向的偏爱。为了确定这些反应是否仍受各自的光照方式控制，欧洲知更鸟，斑马Erithacus rubecula在紫外线，蓝光，蓝绿色和绿色光下以增加的强度进行了测试，以迁移方向的取向作为是否接受磁感受的标准以正常方式工作。结果在424 nm蓝光下，这些鸟类在季节性迁徙方向上定向良好，低强度的502 nm绿松石和565 nm绿光，其定量通量为8 x 10（15）s（-1）m（-2），表明磁接收不受损害。在373 nm的相同数量通量的UV下，它们不在迁移方向上取向，而是显示了对东西轴的偏爱，但是在较低强度的UV下它们在迁移方向上取向很好。强度超过36 x 10（15）量子s（-1）m（-2）的蓝色，蓝绿色和绿色光会引起多种响应：迷失方向，东西方向的航向，南北方向的航向或“固定”方向趋势。随着强度从36 x 10（15）量子s（-1）m（-2）增加到54和72 x 10（15）量子s（-1）m（-2），这些响应发生了变化。结论在迁移方向以外的其他方向上响应的具体表现显然取决于环境光的状况。这意味着，即使正常情况下提供磁罗盘信息的机制似乎已被破坏，由光激活的过程仍然可以控制行为。它表明了不同类型的受体（磁性和视觉）之间的复杂相互作用。尚不清楚所涉及的受体的性质及其连接的细节。但是，建议了色锥在介导磁输入的过程中的作用。它表明了不同类型的受体（磁性和视觉）之间的复杂相互作用。尚不清楚所涉及的受体的性质及其连接的细节。但是，建议了色锥在介导磁输入的过程中的作用。它表明了不同类型的受体（磁性和视觉）之间的复杂相互作用。尚不清楚所涉及的受体的性质及其连接的细节。但是，建议了色锥在介导磁输入的过程中的作用。