The Development of Orientation Mechanisms in Birds

候鸟定向行为的研究及其它 很多动物都非常依赖定向笼 来分析动物的方向选择。 的情况下 鸟，这些通常是圆形的笼子，其中的方向， 记录动物的跳跃或扑动。 的完整性 这些研究的结果显然取决于 研究人员的能力，至少知道，往往控制， 鸟类所受到的刺激。 因为知觉 其他物种的世界往往与我们自己的世界明显不同， 研究人员必须非常小心，以确保他们的 实验对象对感兴趣的刺激做出反应。 候鸟已经被证明使用极化模式 天窗用于定向。 这是一种视觉刺激， 人类几乎不敏感，生理上的 脊椎动物感知偏振光的机制是 未知 此外，从技术上讲， 正是晴空的偏振光模式。 博士 艾伯迄今为止的实验表明，偏振天窗可能是 集中参与开发和执行 几种候鸟的方向。 这些事实 因此仔细研究鸟类的 响应偏光天窗：到什么具体方面 他们会对刺激做出反应，以及他们如何使用这些信息 作为一个指南针？ 了解这些事情将有助于实验者 产生最佳的测试刺激和装置，并将 确保鸟的方向不是基于 测试情况的一些未知方面

Studies of the orientation behavior of migratory birds and other kinds of animals rely heavily on orientation cages as the means of assaying the animal's choice of direction. In the case of birds, these are usually circular cages in which the direction of the animal's hopping or fluttering is recorded. The integrity of the results of such studies obviously depends upon the researcher's ability at least to know, and often to control, the stimuli to which the birds are exposed. Because the perceptual world of other species often differs markedly from our own, researchers must be extremely careful to be certain that their experimental subjects are responding to the stimuli of interest. Migratory birds have been shown to use patterns of polarized skylight for orientation. This is a visual stimulus to which human beings are barely sensitive, and the physiological mechanism by which vertebrates perceive polarized light is unknown. In addition, it is technically impossible to simulate precisely the polarized-light pattern of the clear sky. Dr. Able's experiments to date suggest that polarized skylight may be centrally involved in the development and performance of orientation in several species of migratory birds. These facts make it extremely important to examine in detail the birds' response to polarized skylight: To what specific aspects of the stimulus are they responding, and how do they use the information as a compass? Knowing these things will help experimenters produce an optimal testing stimulus and apparatus, and will ensure that the birds' orientation is not an artifact based on some unknown aspect of the testing situation.