Thanks to these colors, other animals do not see the orcas as a predator. The white oval spots at each side of the head have a double purpose: To other animals, they gives the illusion that the orca is a much more powerful opponent. They also serve as false eyes, protecting the real eyes in case of attack.

Pectoral Fins.

The superior extremities of the Orcas are their pectoral fins. These pectoral fins have most of the bones that make up the front extremities of terrestrial animals, but in the orca, these bones are modified and shortened. These bones are united firmly by connective tissue. Thick cartilage pads lie lengthwise between the bones.

The pectoral flippers are round and paddle like. The blood circulation in the pectoral fins, helps the animal to maintain a stable body temperature. The arteries within the pectoral fins are surrounded by veins.

This way, part of the heat of the blood that travels through the arteries is transferred to the blood that passes through the veins. This heat exchange helps the Orcas to maintain the heat of their body and to regulate its temperature, much like a radiator maintains an automobile engine fresh, but in a inverse way.

When the heat of the body exceeds its limits, the circulation of the blood that passes through the veins near the surface of the fin increases. When it returns to the body, it returns fresher, allowing the body temperature to return to normal levels. A large male Orca may have pectoral flippers up to 6.5 ft. (2 m) long and 4 ft. (1.2 m) wide.

 

X-Ray picture of the Orca pectoral fin.

 

Tail Flukes

The Tail Flukes are flattened pads of tough, dense, fibrous connective tissue, completely without bone. Longitudinal muscles of the back (both above and below the spine) and the caudal peduncle move the flukes up and down.

Just like the pectoral fins, the arteries of the tail flukes are surrounded by veins, which help to maintain a stable body temperature. Tmhe tail flukes of an Orca of great size can measure up to 9 ft. or 2,7 meters from point to point.

Hidden Extremities.

All the outlines of possible hidden extremities have disappeared, except for two smalls cleared pelvic bones, which are well hidden between muscles of the body. These small bones are not connected to the spine.

The Dorsal Fin.

Like the ends of the tail flukes, the dorsal fin is also made of very dense, fibrous connective tissue, that does not contains any bones. The dorsal fin acts like a keel helping to stabilize to the Orca while swims. Also the dorsal fin of an adult male, is much higher and more triangular that that of a female.

Measuring 1,8 meters of height it reaches with facility the 6 ft. In females, the dorsal fin is smaller and may be slightly falcate (curved back). It reaches a height of 3 to 4 ft. (0.9-1.2 m). Both sexes can have dorsal fins of irregular form, sometimes inclined to the left or the right.

As in the pectoral fins and tail flukes, the dorsal fin arteries are surrounded by veins, which help to maintain a stable body temperature.

An Orca dorsal fin. Besides helping to stabilize the animal, it also helps to keep the animal's body temperature stable too.

The Head.

The Orcas have an distinct rostrum that projects like a tromp. The teeth are conical and they interlock. They are designed to grasp and tear more than to chew. The number of teeth varies among individuals. There are usually 14 teeth on each side of the jaw, counting 40 to 58 in total. They typically measure about 3 inches or 7.6 centimeters long and 1 inch or 2.5 centimeter in diameter.

Hidden eyes, Conical Teethes, a Single Blow hole, and a black and white coloration; all this at the service of one of the sea's Top predators: The Orca.

Their eyes, about the same size as the eyes of a bull, are on each side of the head, just behind and above of the mouth. The ears are located behind the eyes, they are small openings, with no external ear flaps. A single blowhole is located on the dorsal surface of the head, and a muscular flap covers it. This flap provides the animal with an excellent water seal.