Meeting Abstract
Various marine animals migrate across vast expanses of ocean before returning as adults to reproduce in the areas where they originated. How animals accomplish such feats of natal homing has remained an enduring mystery. Studies with sea turtles, however, have provided evidence that turtles imprint on the magnetic field of their home area when young and use this information to return as adults. Behavioral experiments indicate that turtles have the sensory abilities needed to detect the unique ‘magnetic signature’ of a coastal area. In addition, analyses have revealed that subtle changes in the geomagnetic field of the home region are correlated with changes in the distribution of nests along beaches. A relationship between population genetic structure and the magnetic fields that exist at nesting beaches has also been detected, consistent with the hypothesis that turtles recognize their natal areas on the basis of magnetic cues. Taken together, the results imply that geomagnetic cues play a central role in the natal homing of sea turtles and, in many cases, can fully account for a turtle’s ability to return to a specific home beach. Similar mechanisms may underlie long-distance natal homing in diverse marine migrants such as fish and marine mammals.
