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While investigation of bird migration and navigation has long incorporated such techniques as direct observation, capture and marking, experimental investigation markedly increased in the mid-twentieth century. Many experiments have employed the orienting behavior of birds kept in captivity, called Zugunruhe, or migratory restlessness. This behavior includes rapid fluttering of the wings and hopping in the direction towards which related birds in the wild would be migrating.

Cornell University behavioral ecologist Stephen Emlen demonstrated that developing birds learn to recognize star patterns that, over time, become a reference system for migratory way-finding. During the 1960's he conducted experiments with caged indigo buntings, in which a star ceiling was manipulated to simulate spring or fall skies, inducing physiological states of migratory readiness in the buntings. The birds were placed in cages having inked blotting pads on their floors. Paper funnels that opened wider at the top enabled the birds' view of the starry ceiling. Responding to the "seasonal changes" in the sky, the buntings quivered and jumped in the direction of their intended migration, leaving inked marks on the side of the funnel. Quantitative records were made of the frequency of jumping in the migratory direction, "northward" in spring, "southward" in autumn. As Emlen turned off some star projections in the planetarium sky, the birds' orientation became poorer. Birds that were raised in conditions that prevented their seeing star patterns were unable to select the normal migration direction. Birds that were raised under a planetarium sky that rotated around the star Betelgeuse in the constellation Orion oriented to Betelgeuse as if it were in the north when they were later placed under a normally oriented night sky.

Related laboratory experiments revealed that European robins changed their orientation in response to shifts in an artificial magnetic field that mimicked the Earth's natural field, and European starlings altered their orientation when mirrors were used to shift the sun's image. Studies have also investigated orientation by wind direction and smell. A clear message emerging from studies of bird orientation and navigation is that birds do not rely on a single source of information for migration cues. Instead, they use overlapping cues from a variety of sources.