The whale is the largest animal that exists today, there is no discussion about it. The fin whale can measure 25 to 30 feet long and weigh 150 to 200 tons. His heart is the size and weight of a small car utility and its body is covered with a thick layer of fat that keeps your body temperature between 36 and 37 degrees, even in very frías.Al waters contrary to what may seem The fat of whales is coated with a thin layer of skin along with the epidermisy also have another layer of fat of 15 cm or more below the skin serves as insulation and nutritional and energy reserves for the time of mating and breeding, which takes place in warm seas where food is in short supply .. The first mentioned secretes a substance which favors wetting hydrodynamics. Her body is slim. The two front limbs are transformed into fins. The hind limbs disappeared. They have also lost their fur, which is reduced to a few bristles, located in the cara.Su body has a large horizontal wing, equipped with a powerful musculature, allowing you to reach, in some species, speeds of 40 to 50 km / h. Except in the fin, which has some flexibility, the cervical vertebrae are welded to the skull. Some whales have a small dorsal fin, which is sometimes reduced to a small ridge and in the sperm whale, or disappears as the gray whale franca.Estos or large mammals, like all breathe air that is why so are possessed of great lungs, breathing through the nostrils that are on top of the head, which close tightly when submerged, opening them when they return to the surface to breathe, producing the characteristic puff of whales.