Camouflage

Camouflage is a clever way that animals, objects, and even people use to hide or blend in with their surroundings. It helps them stay safe by making it harder for others to see them. For example, a leopard's spotted coat helps it disappear among trees and bushes, while a leaf-mimic katydid looks just like a leaf, protecting it from predators.

In the military, soldiers have used special clothing called battledress to hide in battle, especially since the 19th century when more accurate guns made hiding essential for survival. During World War I and World War II, artists designed tricky patterns to disguise ships and vehicles, helping them avoid being found by enemies.

Camouflage isn’t just for nature and war. We also use it in everyday life, like covering cell telephone towers to make them blend into the landscape or using bold camouflage patterns in fashion. It’s a fascinating idea that appears in art, stories, and many other places.

History

In ancient Greece, Aristotle talked about how animals like the octopus can change their colors to hide or to signal others.

Camouflage has been studied in animals for over a century. Charles Darwin suggested that hiding helps animals survive and have more babies. Scientists like Edward Bagnall Poulton and Hugh Cott explored how animals use colors and patterns to blend in with their surroundings. Some animals look like leaves or other objects, while others have bold patterns that break up their shapes to stay hidden.

Evolution

Studying how camouflage develops is challenging because we don't have many fossils showing it. Camouflage needs to help an animal survive in its environment and be passed down through generations. This means we must look at genes and the environment to understand it better.

Fossils of skin from the Cretaceous period show that some sea reptiles had darker backs and lighter bellies to blend in. Insects like lacewings have been hiding this way for over 100 million years by sticking debris on their bodies. There is also evidence that some dinosaurs were camouflaged.

Different animals have different genetic ways to develop camouflage. For example, some sea creatures can change their colors using special genes. In other animals, genes that help with camouflage come from changes and transfers of existing genes. The same genes can help many different animals develop colors that help them hide.

Principles

Further information: List of camouflage methods

Camouflage can be achieved by different methods. Most of the methods help to hide against a background, but some protect without hiding. Methods may be used alone or together. Many ways of hiding work with what we see, but some research has looked at hiding using scent or sound. These methods can also be used for military equipment.

Background matching

Some animals’ colors and patterns match a natural background. This is important for hiding in all environments. For example, tree-dwelling parakeets are mainly green; woodcocks on the forest floor are brown and speckled; reedbed bitterns are streaked brown and buff. Desert animals are almost all desert-colored in tones of sand, buff, ochre, and brownish grey, whether they are mammals like the gerbil or fennec fox, birds such as the desert lark or sandgrouse, or reptiles like the skink or horned viper. Military uniforms, too, often look like their backgrounds; for example khaki uniforms are a muddy or dusty color, originally chosen for use in South Asia.

Disruptive coloration

Main article: Disruptive coloration

Disruptive patterns use strong, contrasting markings such as spots or stripes to break up the outlines of an animal or vehicle, or to hide important features, like the eyes, as in the common frog. These patterns may use more than one method to trick the way we see. Predators like the leopard use disruptive hiding to help them get closer to prey, while prey use it to avoid being seen by predators. Disruptive patterns are common in military use, for both uniforms and vehicles. However, disruptive patterns do not always work on their own, as shape, shine, and shadow can still give away an animal or vehicle.

Countershading

Main article: Countershading

Countershading uses graded color to balance out the effect of shadows, creating a flat look. Shadows make an animal appear darker below than on top, going from light to dark; countershading “paints in” tones which are darkest on top, lightest below, making the animal almost invisible against a suitable background. Countershading is widely used by land animals, such as gazelles and grasshoppers; sea animals, such as sharks and dolphins; and birds, such as snipe and dunlin.

Eliminating shadow

Some animals, such as the horned lizards of North America, have evolved ways to get rid of shadows. Their bodies are flattened, with the sides thinning to an edge; they press their bodies to the ground; and their sides are fringed with white scales which hide and break up any remaining shadow. Some butterflies, such as the speckled wood, Pararge aegeria, minimize their shadows when resting by closing their wings over their backs, aligning their bodies with the sun, and tilting to one side towards the sun.

Distraction

Main article: Distractive markings

Many prey animals have bright, high-contrast markings which strangely draw the predator’s eye. These distractive markings may help hide the prey by keeping the predator from seeing the whole animal, for example by stopping the predator from recognizing the animal’s outline.

Cryptic behaviour

Movement catches the eye of animals looking out for danger, and of predators hunting for food. Most ways of hiding also need behaviour that blends in, such as lying down and staying still to avoid being seen, or in the case of stalking predators such as the tiger, moving slowly and quietly, watching its prey.

Motion camouflage

Main article: Motion camouflage

Most ways of hiding don’t work when the animal or object moves, because the motion is easily seen. However, insects such as hoverflies and dragonflies use motion camouflage: the hoverflies to get close to possible mates, and the dragonflies to get close to rivals when defending areas. Motion camouflage is done by moving so as to stay on a straight line between the target and a fixed point in the landscape; the pursuer thus seems not to move, but only to appear larger in the target’s view.

Mimesis

Further information: Mimicry and Cryptic aggressive mimicry

In mimesis (also called masquerade), the hidden object looks like something else which is not special to the observer. Mimesis is common in prey animals, for example when a peppered moth caterpillar looks like a twig, or a grasshopper looks like a dry leaf. It is also found in nest structures; some wasps build a nest envelope in patterns that look like the leaves around the nest.

Motion dazzle

Not to be confused with dazzle camouflage.

Most ways of hiding are made ineffective by movement: a deer or grasshopper may be very hard to see when still, but instantly seen when it moves. But one method, motion dazzle, needs rapidly moving bold patterns of contrasting stripes. Motion dazzle may make it harder for predators to know the prey’s speed and direction accurately, giving the prey a better chance to escape. Motion dazzle distorts how speed is seen and is most effective at high speeds. As of 2011, motion dazzle had been suggested for military vehicles, but never used. Since motion dazzle patterns would make animals harder to find when moving, but easier to see when still, there would be a balance between motion dazzle and hiding.

Mechanisms

Animals can hide by changing their looks to match their surroundings. For example, chameleons and octopuses can shift their skin colors and patterns thanks to special cells, helping them blend in. Some animals, like the Arctic fox, change their fur color with the seasons—from brown in summer to white in winter.

Other creatures decorate themselves with leaves, sand, or shells to break up their shapes and look more like their environment. This trick is also used by people, like when soldiers wear special outfits covered in plants to stay hidden. Some sea animals, like jellyfish, are mostly see-through, which makes them hard to spot in the water. Fish such as sardines and herring have silvery skin that shines and hides them from predators.

Applications

Military

Main articles: Military camouflage and List of military clothing camouflage patterns

The use of camouflage in military settings began long ago. In ancient times, pirate ships were sometimes painted in colors to hide them. Later, during big battles, soldiers started using special clothing to blend into their surroundings. This helped them stay safe while moving or hiding.

During the 1800s, as weapons became more accurate, soldiers needed better ways to stay hidden. Some armies began wearing green jackets to blend into forests. In the 1900s, many armies painted their buildings and vehicles to match their environments. This made it harder for enemies to see them from a distance.

In both World Wars, artists helped design ways to hide soldiers, vehicles, and even whole towns. They used colors and patterns to break up shapes, making it difficult for enemies to spot what was hidden. Even airplanes and ships were painted special colors to stay hidden from view.

Hunting

Hunters have also used camouflage for a long time. They wear clothing that matches the forest or field to get closer to animals without being noticed. Modern hunters use special fabrics with patterns that break up their shape, helping them stay hidden.

Civil structures

Sometimes, buildings or towers are painted to look like something else. For example, in some places, tall towers are made to look like trees to fit better with their surroundings. This helps them blend in and not stand out too much.

Fashion, art and society

Camouflage patterns have also become popular in fashion and art. Artists and designers have used these patterns in clothes and paintings, sometimes to make a statement about war or to create interesting designs. These patterns can be found in many places, from protest marches to fashion shows.