Wiltschko Wolfgang, Möller Andrea, Gesson Marcus, Noll Catrin, Wiltschko Roswitha
Fachbereich Biologie und Informatik, Zoologie, J. W. Goethe-Universität Frankfurt, Siesmayerstrasse 70, D-60054 Frankfurt am Main, Germany.
J Exp Biol. 2004 Mar;207(Pt 7):1193-202. doi: 10.1242/jeb.00873.
In previous experiments, migratory birds had been disoriented under 635 nm red light, apparently unable to use their magnetic compass. The present study with European robins, Erithacus rubecula, confirms these findings for red light at the levels of 6 x 10(15) quanta s(-1) m(-2) and 43 x 10(15) quanta s(-1) m(-2), suggesting that the disorientation under red light was not caused by the test light being below the threshold for magnetoreception. However, pre-exposure to red light for 1 h immediately before the critical tests under red light of 6-7 x 10(15) quanta s(-1) m(-2) enabled robins to orient in their seasonally appropriate migratory direction in spring as well as in autumn. Pre-exposure to darkness, by contrast, failed to induce orientation under red light. Under green light of 7 x 10(15) quanta s(-1) m(-2), the birds were oriented in their migratory orientation after both types of pre-exposure. These findings suggest that the newly gained ability to orient under red light might be based on learning to interpret a novel pattern of activation of the magnetoreceptors and hence may represent a parallel to the previously described enlargement of the functional window to new magnetic intensities. Mechanisms involving two types of spectral mechanisms with different absorbance maxima and their possible interactions are discussed.
在之前的实验中，候鸟在635纳米的红光下迷失了方向，显然无法使用它们的磁罗盘。目前对欧洲知更鸟（欧亚鸲）的研究证实了在6×10¹⁵ 量子·秒⁻¹·米⁻² 和43×10¹⁵ 量子·秒⁻¹·米⁻² 水平的红光下的这些发现，这表明红光下的迷失方向并非由测试光低于磁感受阈值所致。然而，在6 - 7×10¹⁵ 量子·秒⁻¹·米⁻² 的红光下进行关键测试前1小时预先暴露于红光，使知更鸟能够在春季和秋季按照季节性适宜的迁徙方向定向。相比之下，预先暴露于黑暗中未能在红光下诱导定向。在7×10¹⁵ 量子·秒⁻¹·米⁻² 的绿光下，两种类型的预先暴露后鸟类都能按其迁徙方向定向。这些发现表明，新获得的在红光下定向的能力可能基于学习解读磁受体激活的新模式，因此可能类似于之前描述的功能窗口向新的磁场强度扩大。文中讨论了涉及具有不同最大吸收波长的两种光谱机制及其可能相互作用的机制。
