| Summary: | Animal species from nearly all major taxa show migratory behavior, and some of these animals cover remarkable distances. Well studied examples are migratory birds like the arctic tern Sterna paradisaea that migrates from boreal and high Arctic breeding grounds to the Southern Ocean (Egevang et al., 2009). Insects also attain excellent achievements in annual migration as shown by the monarch butterfly Danaus plexippus which changes its habitat between eastern North America and central Mexico (Kyriacou, 2009). How can these animals perform such remarkable migrations? Which mechanisms underlie such a performance? Foraging ants and bees use navigational strategies similar to those of birds and mammals to reach a goal. To navigate through familiar terrain, all of these species use path integration and memories of visual landmarks (Collett & Collett, 2002). During path integration, an animal permanently updates a homing vector resulting from all angular and translational movements so that it can always take a direct path back to its starting point (Collett & Collett, 2000). To compute resulting novel routes out of several single homing flights, bees use a map-like navigation strategy that allows targetoriented decisions at any place and toward any intended location within the familiar terrain (Menzel et al., 2006). These mechanisms are used for near-range navigation, termed as "homing", rather than for long-distance navigation tasks. Animals that navigate through unknown space are forced to use cues of a global nature, such as the geomagnetic field, the stars, and cues related to the position of the sun (Frost & Mouritsen, 2006). Like diverse marine animals, e.g. marine turtles, lobsters, and molluscs, the green sea-turtle Chelonia mydas has a magnetic map sense for navigation to specific targets (Cain et al., 2005; Lohmann et al., 2004). Many diurnal species use a time-compensated sun-compass, other sky compass cues like polarized light, or stars for steering toward distant targets (Wehner, 1984; Homberg, ...
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