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AnimalsCompasses Researchers have found that migrating animals use a variety of innercompasses to help them navigate. Some steer by the position of the Sun. Othersnavigate by the stars. Some use the Sun as their guide during the day andthen switch to star navigation by night. One study shows that the homingpigeon uses the Earths magnetic fields as a guide in finding its way home and there are indications that various other animals from insects tomollusks, can also make use of magnetic compasses. It is of course veryuseful for a migrating bird to be able to switch to a magneticcompass when clouds cover the Sun; otherwise it would just have to land andwait for the Sun to come out again.Even with the Sun or stars to steerby, the problems of navigation are more complicated than they might seemat first. For example, a worker honeybee that has found a rich source ofnectar and pollen flies rapidly home to the hive to report. A naturalisthas discovered that the bee scout delivers her report through a complicateddance in the hive, in which she tells the other workers not only how faraway the food is, but also what direction to fly in relation to the Sun. Butthe Sun does not stay in one place all day. As the workers start out to gather the food, the Sun may alreadyhave changed its position in the sky somewhat. In later trips during the day,the Sun will seem to move farther and farther toward the west. Yet the workerbees seem to have no trouble at all in finding the food source. Their innerclocks tell them just where the Sun will be and they change their coursecorrespondingly. | 
