Animals use different types and methods of camouflage to conceal their appearances. Preys and predators can avoid being seen from each other through the usage of camouflage. The common types of camouflage are background matching, disruptive coloration, mimicry, and countershading.
Types of camouflage
In background matching, animals resemble (mimic) the appearance of their surroundings in order to avoid conspicuity. Some animals like flounders match themselves with the general color and pattern of their surroundings. Other animals conceal themselves through disguising as a specific part of their environment, like how walking leaves disguise themselves as leaves.
Walking Leaf
Disruptive coloration causes a visual disruption by creating false boundaries. For instance, the stripes of zebras serve as disruptive coloration that conceals individual zebras when they are clustered as a herd. This may increase the chance of survival of the zebras when in a herd.
Mimicry is when animals mimic other organisms (usually of toxic and other dangerous qualities) to conceal their identities. For example, coral snakes have brightly colored striped patterns that warn others of its deadly poison. Then, other harmless species, such as the scarlet king snake, may mimic those patterns to disguise themselves as deadly coral snakes.
In countershading, animals have dark-colored tops and light-colored undersides, which allow them to blend into the environment. For example, when seen from above, sharks’ dark upper sides conceal sharks to the dark water below. When seen from below, sharks’ bright undersides help them blend in with the light-colored surface water.
How animals achieve camouflage
Animals achieve camouflage either through evolving their fixed body patterns or through changing their body patterns based on their environmental changes.
Animals with fixed body patterns achieve camouflage through blending into their typical environment. They develop body patterns that fit their general surroundings over a long period of time through natural selection.
Other animals change their body patterns based on environmental changes. The timescale for achieving these pattern changes vary depending on the species. For instance, arctic foxes seasonally change their fur color over months. They have white fur in the winter and brown fur in the summer, which are based on predictable environmental changes. Crabs change their colors over hours based on circadian rhythms. Some animals like cuttlefish rapidly change their colors within seconds, appropriately adapting their body patterns to different backgrounds. Such rapid changes are usually achieved through changes in chromatophores, or pigment-containing cells, guided by visual pathways. The visual system drives changes in chromatophores either through direct nerve control or through hormones.
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