Orientation in birds. The sun compass.

摘要: The sun compass was discovered by G. Kramer in caged birds showing migratory restlessness. Subsequent experiments with employing directional training and clock shifts, carried out Hoffman Schmidt-Koenig, showed that the azimuth is used, altitude ignored. In laboratory, McDonald found accuracy to be +/- 3 degrees(-)+/- 5 degrees. According Hoffmann trained at medium northern latitudes were able allow for sun's apparent movement north of arctic circle, but not equatorial trans-equatorial latitudes. homing experiments, Schmidt-Koenig demonstrated used pigeons during initial orientation. This finding principal evidence existence a map-and-compass navigational system. Pigeons living utilize even under extreme solar conditions equinox, achieving angular resolution about degrees experiments. preliminary analyses, pigeons' ephemerides are retarded several weeks (Ranvaud, Ganzhorn et al.).