Penguins are camouflaged to look like the ocean from above and the sky from below.

This color pattern is called countershading. It is also known as Thayer's Law. It was named after Abbott Handerson Thayer who wrote about it in 1909. Many marine animals like sharks and tuna use this same trick to hide.Predators like the Leopard Seal hunt mostly by using their eyes. Research shows that countershading makes it 50 percent harder for predators to see their prey. The dark feathers on a penguin's back contain a pigment called eumelanin. This pigment makes the feathers stronger so they do not wear out as fast.The white feathers on a penguin's belly reflect about 80 percent of the light coming from the surface. This matches the bright sky above the water. The dark feathers on the back absorb about 90 percent of the light. This matches the darkness of the deep sea. By matching the light from different angles, the penguin disappears into its environment.