The majority of small tooth whales are called dolphins. They are mammals of the order Cetacea and the families Plantanistidae and Delphinidae and include about 50 species. All have a beak like snout and sharp, conical teeth. Most dolphin species are about 6 ft in length, the males averaging 4 to 8 in longer than females. The largest is the killer whale, which can be 19-22ft long and weigh between 8000-10000lbs. One of the largest dolphins is the bottle-nose dolphin which can reach over 9ft in length and weigh 440 lbs. The smallest species is the buffeo, found in the Amazon River. The buffeo rarely grows over 3,9 ft in length and 66 lbs in weight, really smalled compared to the bottle_nose. The body is sleek and smooth and the hairless skin is rubbery to the touch. Most species have jaws that protrude into a beak like snout. Above the upper jaw is a large mass of fat and oil-containing tissue forming the so-called "melon" that looks much like a bulging forehead. Because dolphins are mammals, they must breathe air and maintain a high body temperature. The internal temperature, between 97,9 deg to 99 deg F, is acheived by a thick layer of blubber under the skin. Air is breathed through blowhole, situated almost directly on top of the head. The dolphin normally comes to the surface to breathe about every two minutes, and each breath consists of a short, almost explosive exhalation, followed by a slightly longer inhalation. Dolphins can hold their breath for up to several minutes and are capable of rapid and deep dives of more then 1,000 ft…
