Cryptic coloration with the upper surface darker than the lower surface.

Type of camouflage as seen in most fish and cetaceans, which dark upperparts and lighter undersides. This makes the animal harder to see from predators above or below.

two-tone coloring of frogs, to hide them from predators

This is a form of protective coloration in which animals are darker on their upper (dorsal) surface than on their lower (ventral) surface. Many sharks, especially those that live near the surface, are a a dark color on their backs and a lighter color on their bellies. The countershading camouflages them from two directions -- looking up at them against the surface, and looking down at them against the sea floor.

Countershading is a type of body coloration that sharks, some whales, and some other animals have in which the top and bottom sides are colored differently, serving to camouflage the animal from multiple perspectives. In sharks, the top is much darker than the belly. When the shark is viewed from above, its dark top surface blends into the dark ocean depths or ocean floor; when viewed from below, the light-colored belly blends in with the light above. This helps the shark hunt in a stealthy manner, enabling it to sneak up on prey undetected.

also known as obliterative shading; enables the fish to effectively hide from its prey or predators that may be above and below

Countershading, or Thayer’s Law, is a form of camouflage. Countershading, in which an animal’s pigmentation is darker dorsally, is often thought to have an adaptive effect of obliterating conspicuous shadows cast on the ventral region of an animal’s body. In essence the distribution of light on objects that are lit from above will cause unequal reflection of light on a solid body of uniform colour, such shadows could provide predators with visual cues to a prey's shape and projection.