Deutschlander ME, Phillips JB, Borland SC
Indiana University, Department of Biology (and the Center for the Integrative Study of Animal Behavior), Bloomington, IN 47405, USA.
J Exp Biol. 1999 Apr;202 (Pt 8):891-908. doi: 10.1242/jeb.202.8.891.
Light-dependent models of magnetoreception have been proposed which involve an interaction between the magnetic field and either magnetite particles located within a photoreceptor or excited states of photopigment molecules. Consistent with a photoreceptor-based magnetic compass mechanism, magnetic orientation responses in salamanders, flies and birds have been shown to be affected by the wavelength of light. In birds and flies, it is unclear whether the effects of light on magnetic orientation are due to a direct effect on a magnetoreception system or to a nonspecific (e.g. motivational) effect of light on orientation behavior. Evidence from shoreward-orienting salamanders, however, demonstrates that salamanders perceive a 90 degrees counterclockwise shift in the direction of the magnetic field under long-wavelength (>=500 nm) light. A simple physiological model based on the antagonistic interaction between two magnetically sensitive spectral mechanisms suggests one possible way in which the wavelength-dependent effects of light on the salamander's magnetic compass response might arise. Assuming that the wavelength-dependent characteristics of the avian magnetic response can be attributed to an underlying magnetoreception system, we discuss several hypotheses attempting to resolve the differences observed in the wavelength-dependent effects of light on magnetic orientation in birds and salamanders. By considering the evidence in the context of photoreceptor- and non-photoreceptor-based mechanisms for magnetoreception, we hope to encourage future studies designed to distinguish between alternative hypotheses concerning the influence of light on magnetoreception.
已经提出了依赖光的磁感受模型，该模型涉及磁场与位于光感受器内的磁铁矿颗粒或光色素分子的激发态之间的相互作用。与基于光感受器的磁罗盘机制一致，蝾螈、苍蝇和鸟类的磁定向反应已被证明会受到光波长的影响。在鸟类和苍蝇中，尚不清楚光对磁定向的影响是由于对磁感受系统的直接作用，还是由于光对定向行为的非特异性（例如动机）作用。然而，来自向岸定向蝾螈的证据表明，蝾螈在长波长（>=500 nm）光下会感知到磁场方向逆时针旋转90度。基于两种磁敏感光谱机制之间的拮抗相互作用的简单生理模型表明了一种可能的方式，即光对蝾螈磁罗盘反应的波长依赖性效应可能由此产生。假设鸟类磁反应的波长依赖性特征可归因于潜在的磁感受系统，我们讨论了几种假设，试图解决在光对鸟类和蝾螈磁定向的波长依赖性效应中观察到的差异。通过在基于光感受器和非光感受器的磁感受机制的背景下考虑证据，我们希望鼓励未来的研究，以区分关于光对磁感受影响的替代假设。
