Among the most numerous species of dolphins are spinner dolphins, which sometimes spin on their sides when they leap out of the water. Many kinds of dolphins have distinguishing colors or other markings. For example, Risso's dolphins are brown and gray, and most of them have many irregular white streaks. White-sided dolphins have gray, white, and yellow stripes on their sides. Spotted dolphins are named for their white spots.
Striped dolphins have black stripes on their sides.
The bodies of dolphins All dolphins have torpedo-shaped bodies, which enable the animals to move through the water quickly and easily. They have a pair of paddle-shaped forelimbs called flippers, but no hindlimbs. Most species of dolphins also have a dorsal fin on their back. This fin, along with the flippers, helps balance the animal when it swims. Powerful tail fins, called flukes, propel dolphins through the water.