The largest known fish. In spite of the common name whale it is not a mammal but a fish.

The classes of fish include jawless fish (agnatha), bony fish (Osteichthyes), lungfishes, and cartilaginous fish like this shark.

Cartilaginous fish like sharks, skates, and rays, have skeletons made of cartilage which is more flexible and softer that bone.

Lungfish can survive the seasonal drying out of their freshwater lakes, by burrowing and creating a cocoon.

Fish are divided into 2 superclasses, jawless (agnatha) and jawed (gnathostomata). Hagfish, and lampreys, like this one, are jawless fishes.

Bony fish are the most common class of fish, and live in both salt and fresh water.

This fish is an example of a living fossil.

Cave dwelling fish like this one, have evolved eyelessness.

Angler fish have evolved their own lures to attract prey.

Jawless fishes have mouths like suction cups, and tongues that can protrude and have teeth on them.

A jawless fish (agnatha).