Many animals are able to navigate using the Sun as a compass. Orientation cues from the position of the Sun in the sky are combined with an indication of time from the animal's internal clock. There is evidence that some animals can navigate using celestial cues, such as the position of the Sun. Since the Sun apparently moves in the sky, navigation by this means also requires an internal clock. Many animals depend on such a clock to maintain their circadian rhythm. Animals that use sun compass orientation are fish, birds, sea turtles, butterflies, bees, sandhoppers, reptiles, and ants. Sun compass orientation is using the Sun's position in the sky as a directional guide. The azimuth can be used along with sun compass orientation to help animals navigate. The Sun's azimuth can be defined as the direction of a celestial object from the observer, expressed as the angular distance from the north or south point of the horizon to the point at which a vertical circle passing through the object intersects the horizon.
Purpose of sun compass orientation
Sun compass orientation can be used as a daily guide for animals but for some, including sea turtles, they use the sun as a migratory guide. Turtles use the sun's azimuth compensation schedule in order to find their specific breeding locations each year. Sandhoppers use the sun daily to determine where their home lays. With this experiment a group of sandhoppers were subjected to six hours of artificial lights and their movements were monitored when exposed to normal sunlight. The sandhopper's orientation when finally exposed to normal sunlight, showed that their orientation was off by 90 degrees when in respect to their home. This study helped show how an artificial light can alter the species relationship to the sun and how it can throw off the species basic directional abilities In terms of high elevations, sun compass decreases its precision when providing information to animals. A study was performed to see if dung beetles respond better to orientations provided by the sun compass or skylight compass. The results of this study showed that dung beetles use their original bearings (i.e. sun compass) a majority of the time and rarely use skylight compass. Fish larva find safety in the coral reefs for predators. The particular coral reef is one that the larva have been to before. The larva can recognize the area by the smell, sound, and direction of the particular reef. Fish larvae drift away from the reef and swim in order to relocate their reef. They use sun compass as one of their tools. Different cues are learned and remembered by the fish larva which allows them to return to their reef. It was also concluded that the learning process happens when the fish larvae are young and location can be memorized and become second nature. This is a useful tool that helps fish larva return to their respective reefs. Desert ants use sun compass as a reference to the amount of walking distance to their specific destination. Ants, like bees, compensate for the sun's daily movements as it moves and rotates about the Earth. They communicate to other ants who have already been out and base their directions on the direction they should go. In addition to sun compass, insects such as ants also use a tool called azimuthal position of the sun. These are additional cues determined by ants and passed on to other ants when they communicate.
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