By Susan Milius
During their fall migration season, certain sparrows sleep only about a third as much as they do at other times of the year, but they manage to keep up their performance on tests of learning, a new lab study indicates. Outside the migration season, however, birds with disrupted sleep slump in learning tasks.
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Niels C. Rattenborg of the University of Wisconsin–Madison and his colleagues say in the July Public Library of Science Biology that this finding of no-cost sleep deprivation is “unprecedented.”