Human beings shed hair and skin all the time, but elephant seals go through a catastrophic molt, in which the entire layer of skin with the hairs attached is sloughed off in one concentrated time.The reason for this abrupt molt is that while at sea they spend most of their time in cold deep water. As part of the dive process the blood is diverted away from the skin. This helps them conserve energy and avoid losing body heat. By coming up on land to molt the blood can be circulated to the skin so a new layer of epidermis and hair can be grown. / http://www.elephantseal.org /