Whales are so well insulated that they stay quite warm 24-36 hours after death. Whalers must process the whales quickly, for otherwise, at the elevated body temperature, decomposition proceeds most rapidly and ruins much of the meat. It is possible that the baleen-bearing whales do not cross the warm equatorial waters because they overheat. No one has yet determined whether the newborn young have a sufficient layer of fat to protect them from the cold water, and it has been suggested that whales calve in temperate waters to prevent the babies from being chilled. However, there are species like the narwhal and the white whale which calve in Arctic waters. _Buoyancy_ Another aspect to the extensive deposits of fat is that these tissues are lighter than water and help counteract the heaviness of the whale’s body so that with the assistance of the lungs neutral buoyancy is achieved. The fat is accumulated in between the muscle strands, and in fact, in every available nook and cranny. _Food Storage_ Much of this fat is drawn upon for food. Whenever a whale is existing on its fatty tissue, acetone is one of the waste products which must be eliminated in the breath. This pungent material makes the breath very strong and noticeable at these times. Certainly among whales, there is no stigma attached to being fat or having halitosis. Ordinarily fatty tissues only accumulate when there is a surplus of food over the needs of the animal. You might suspect that whales would need to stockpile fat first, in order to remain warm and buoyant, and that growth would be curtailed and accomplished last. However, studies on the growth of whales show that the efficiency of food gathering is so high and food so plentiful, that growth not only continues but at a tremendous pace. Sexual Maturity