There are many animals throughout nature that have natural camouflage the help them blend into their environment, conceal their shape and avoid their environments.
There are many forms of natural camouflage. One form is mimicry. This is where an animal looks like something else like a leaf, a twig or a more dangerous animal. Some mimics even simulate natural movement like a leaf in the wind.
Another form is a chromatic response, changing color in changing environments, either seasonally (ermine, snowshoe hare) or far more rapidly with chromatophores in their integument (chameleon, the cephalopod family).
Some animals, notably in aquatic environments, also take steps to camouflage the odors they create that may attract predators.
Some herd animals adopt a similar pattern to make it difficult to distinguish a single animal. Examples include zebras' stripes and the reflective scales on fish.
Countershading (or obliterative camouflage), the use of different colors on upper and lower surfaces in graduating tones from a light belly to a darker back, is common in the sea and on land. This is sometimes called Thayer's law, after Abbott H. Thayer who published a paper on the form in 1896.