Overwintering strategies of Antarctic organisms

Abstract

The extremity of winter conditions in the present-day polar regions is unique on Earth. Each year organisms are subjected to extremes of temperature and depending on latitude, prolonged periods of darkness. Organisms have adapted to these extremes through a variety of overwintering strategies that range from physiological changes to alterations in geographical distributions. Some adaptations are specific to just a few taxa, such as huddling by penguins, a strategy that is also seen in some Arctic mammals. However, other strategies are common to a wide diversity of taxa, such as fat storage throughout the winter or migratory avoidance behavior. Although many organisms have specifically adapted to polar conditions, it is also apparent that for many, survival of the Antarctic winter draws upon an inherent phenotypic plasticity particularly amongst the invertebrates. In this review the adaptations of a wide range of organisms to the polar winter environment are discussed. This review concentrates on the Antarctic, although the Arctic is discussed for comparison where appropriate.Keywords: winter, overwintering, polar, Arctic, Antarctic.