Crypsis

In ecology, crypsis is the ability of an animal to avoid observation or detection by other animals. It may be a predation strategy or an antipredator adaptation. Methods include camouflage, nocturnality, lifestyle, and mimicry. Crypsis can involve visual, olfactory (with pheromones), or auditory concealment. When it is visual, the term cryptic coloration, effectively a synonym for animal camouflage, is sometimes used, but many different methods of camouflage are employed by animals.

There is a strong evolutionary pressure for animals to blend into their environment or conceal their shape, for prey animals to avoid predators and for predators to be able to avoid detection by prey. Exceptions include large herbivores without natural enemies, brilliantly-colored birds that rely on flight to escape predators, and venomous or otherwise powerfully armed animals with warning coloration. Cryptic animals include the tawny frogmouth (feather patterning resembles bark), the tuatara (hides in burrows all day; nocturnal), some jellyfish (transparent), the leafy sea dragon, and the flounder (covers itself in sediment).

Methods of crypsis include (visual) camouflage, nocturnality, and subterranean lifestyle. Camouflage involves a variety of methods, from disruptive coloration to transparency and some forms of mimicry.

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