There are several ways in which animals can camouflage themselves against the surrounding environment.
Countershading
Countershading is a form of camouflage used by animals where one side of the animal is darker than another.
Often, in the animal kingdom, an animal’s back (dorsal side) is dark while its underside (ventral side) is light.
In 2017, an immaculately preserved fossil of an armoured dinosaur was found that is believed to have used this form of camouflage.
Despite being 18-foot-long and weighing nearly 3,000-pounds, the dinosaur was still huned enough for evolution to prefer camouflage over confrontation.
Colour change
Many animals can change their colour to blend in with their environment.
Chamaeleons have two superposed thick layers of iridescent cells that have pigment and reflect light.
There are tiny crystal in the upper layer of the skin of chameleons and depending on how relaxed they are, the nanocrystals become closer together or further apart.
This movement alters the wavelength of light that is reflected and therefore appears a different colour to the eye.
Animals such as squid and octopus change colour using specific cells called chromatophores, which change the colour of the skin.
These chromatophores are specialist cells that are controlled by nerves which alters how much the pigment sac is changed and therefore a difference in colour.
Snowshoe hares have a brown coat during the summer but develop a white pelt in the winter to avoid being easily spotted by predators
These changes can occur almost instantaneously and are controlled by nerves or chemicals in the body.
Some mammals such as arctic foxes and Snowshoe hares change the colour of their pelt over time in line with the increased snowfall associated with winter.
Snowshoe hares have a brown coat during the summer but develop a white pelt in the winter to avoid being easily spotted by predators.
Textural manipulation
As well as colour change they can manipulate the texture of their skin in order to blend in with the terrain.
The surface texture of an animals skin can also go a long way towards helping it blend in against its background, especially if the background is rough.
Octopus and squid for example often live on rocky coral reefs or the sea floor where the texture is very uneven.
By contracting their papillae – tiny muscles in the surface of their skin – they can mimic different textures.