Crypsis

Crypsis is the evolutionary strategy by which an organism avoids detection by other organisms, typically by predators, prey, or parasites. It encompasses camouflage, masquerade, and other adaptations that reduce the chance of being noticed or identified. Crypsis can be visual, olfactory, or acoustic, and may involve morphology, behavior, and physiology. In many contexts, it is a form of concealment that allows an organism to approach or escape without alerting others.

Visual crypsis includes background matching, where coloration and texture resemble the surroundings; disruptive coloration that breaks up body outlines; countershading, which reduces silhouette; transparency or translucence that renders parts of the body nearly invisible; and masquerade, when an organism resembles an inedible object such as a leaf or twig. Behavioral strategies such as stillness, waiting in shadows, or moving in ways that minimize detection also contribute to crypsis. Some species combine multiple strategies and show seasonal or ontogenetic changes in appearance.

Non-visual crypsis can involve chemical camouflage to mask scents or reduce olfactory detectability, as well as acoustic strategies that minimize detection by echolocating or listening predators. The term also extends to mimicry of local cues or habitats to blend into an ecological niche.

Examples include the peppered moth (Biston betularia), which shifted its population pattern with industrial soot; cephalopods such as octopuses and cuttlefish that rapidly alter skin patterns; leaf insects and other cryptic arthropods that resemble leaves; and polar animals that blend with snow or ice. Crypsis is subject to trade-offs with other demands such as mating, thermoregulation, or signaling, and evolves under predator–prey arms races and environmental change.