Crypsis

Camouflage can be achieved by a wide variety of methods, from disruptive coloration to transparency and some forms of mimicry, even in habitats like the open sea where there is no background.

Countershading, 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.

The decorator crabs attach plants, animals, small stones, or shell fragments to their carapaces to provide camouflage that matches the local environment.

[11] Pirate perch (Aphredoderus sayanus) may exhibit chemical crypsis, making them undetectable to frogs and insects colonizing ponds.

[13] Some insects, notably some Noctuid moths, (such as the large yellow underwing), and some tiger moths, (such as the garden tiger), have been supposed to defend themselves against predation by echolocating bats, both by passively absorbing sound with soft, fur-like body coverings and by actively creating sounds to mimic echoes from other locations or objects.

The active strategy was described as a "phantom echo" that might therefore represent "auditory crypsis" with alternative theories about interfering with the bats' echolocation ("jamming").