MAGNETOSENSORY ORIENTATION

有证据表明，某些动物能够探测并确定自己的方位， 地球的磁场。 这一能力可用于以下方面： 例如归巢、寻找配偶和寻找食物来源。 虽然 用于转换地磁生物传感器的存在可以 从不同动物的定向反应中推断， 已知的机制转导的地磁能量到 任何多细胞动物的神经系统。 发现了一种动物，它有两个不寻常的特征， 提供了一个机会，以实现对 地磁感觉的物理/生物学基础。 海洋 裸鳃类软体动物Tritonia diomedia对地球磁场的反应 当其他线索不可用时，通过适当地定向来确定字段。 其次，在最近的实验中，一对对称的可重新识别的 已经发现动物大脑中的神经元对大脑的变化做出反应。 环境磁场的方向通过发射电 冲动 在这个建议中，实验描述了行为， 神经生理学和分子水平，旨在（1.） 建立正常的行为环境和使用地磁 信息，（2）在携带信息的感觉输入之间建立相互作用 关于趋流（水流）和地磁线索的信息，以及 (3)细胞/分子实验，以确定生理作用 在与磁感应有关的神经元中发现的独特肽 一体化 很少有人知道动物的感觉或其他过程， 与地球磁场的相互作用，或与更强的磁场相互作用， 领域的 这些研究可能有助于阐明这些关系。

Evidence indicates that certain animals detect and orient themselves to the earth's magnetic field. This capacity may be used in the context of homing, finding mates, and locating food sources, for instance. Although the existence of biosensory apparatus for transducing geomagnetism can be inferred from the orienting responses of diverse animals, little is yet known of the mechanisms of transduction of geomagnetic energy into the nervous system of any multicellular animal. An animal has been found which has two unusual features and which provides an opportunity to achieve an understanding of the physical/biological basis for the geomagnetic sense. The marine nudibranch mollusc, Tritonia diomedia responds to the earth's magnetic field by orienting appropriately when other cues are unavailable. Secondly, in recent experiments, a symmetrical pair of re-identifiable neurons in the animal's brain have been found which respond to changes in the direction of the ambient magnetic field by firing electrical impulses. In this proposal, experiments are described at the behavioral, neurophysiological and molecular level that are designed to (1.) establish the normal behavioral context and use of geomagnetic information, (2) establish interaction between sensory inputs carrying information about rheotactic (water current) and geomagnetic cues, and (3) cellular/molecular experiments to determine the physiological roles of unique peptides found in neurons involved in magnetosensory integration. Little is know of the sensory or other processes in animals which mediate interactions with the earth's magnetic field, or with stronger magnetic fields. These studies may help elucidate these relationships.