re flattened pads of tough, dense, fibrous connective tissue, completely without bone. A large male killer whale may have tail flukes measuring up to nine feet from tip to tip.All traces of hind limbs have disappeared except for two reduced, rod- shaped pelvic bones, which are buried deep in the body muscle. These reduced hind limbs are not connected to the vertebral column however.The dorsal fin, like the flukes, is made of dense, fibrous connective tissue with no bones. It acts as a keel, stabilizing a killer whale as it swims. The arteries in this fin help to maintain body temperature. In males, the dorsal fin is tall and triangular and in females it may by slightly curved back. It both males and females, the dorsal fin may lean to the right or left, being classified as irregularly shaped.A killer whale has a distinct snout-like projection. The teeth are conical and interlocking and are designed for grasping and tearing, rather than chewing. An individual may have between ten and fourteen teeth on each side of the jaw. (About 40 to 58 teeth total.) They are about three inches long and one inch in diameter.The eyes of a killer whale are similar to the eyes of a cow: big, on each side of the head, and just behind and above the mouth.The ears are located just behind the eyes and are small with inconspicious openings, with no external ear flaps.A single blowhole is located on the dorsal surface of the head and is covered by a muscular flap. This flap provides a water-tight seal. This is the only way a killer whale can breath, through the blowhole. It is usually in a closed, relax position and can be opened when the killer whale contracts the muscular flap.Senses:Hearing. Killer whales have developed acute senses of hearing over the years. They have responded to tones within the frequency range of about 0.5 to 100 kHz. (The average range for humans is about 0.02 to 17 kHz.)Most sound reception, or hearing, probably takes places through th...
