Animal colour facts for kids

A brilliantly-coloured oriental sweetlips fish (Plectorhinchus vittatus) waits while two boldly-patterned Cleaner fish pick parasites from its skin. The spotted tail and fin pattern of the Sweetlips signals sexual maturity; the behaviour and pattern of the Cleaner fish signal their availability for cleaning service, rather than as prey

Peacock butterfly is a cryptic leaf mimic when its wings are closed

Peacock butterfly displays startling eye-spots when its wings are open; they also distract attacks away from the body. This insect has survived a bird's attack on the eyespot on the right hindwing

Red underwing moth is cryptic and disruptively patterned at rest

Red underwing moth's startling underwing flash when disturbed

The zebra's bold pattern may momentarily confuse chasing lions: a dazzle defence

Animal colour (or coloration) is produced by light reflecting from an animal's surface. The ways animals produce colours include pigments, chromatophores and other structures, and bioluminescence.

Since sight is usually so important to animals, and is so often used by predators as a long-range way to find prey, an animal's colour must serve one or more functions. These functions, such as finding prey, or evading capture, or finding a mate, are absolutely essential for life and survival. Therefore, animal colour is determined by natural selection because it affects the survival of animals and their offspring.

Some of the most obvious functions of colour are:

1. Camouflage: enabling an animal to remain hidden from view
2. Signalling to other animals
   1. Warning colouration: signalling to other animals not to attack
   2. Mimicry: taking advantage of another species' warning coloration
   3. Sexual selection: finding a mate
   4. Other kinds of signalling
3. Diversion
   1. Startle defence: unexpected flashes of colour or eyespots
   2. Dazzle: confusing a predator by moving a bold pattern (such as zebra stripes) rapidly
4. Physical protection: such as humans in tropical climates have dark skin pigments which protect against sunburn and skin cancer.
5. Incidental colouration. This is common in plants, which have green leaves because chlorophyll is green. In animals it is rare, such as having red blood (haem, needed to carry oxygen, is red). However, when the red shows on the surface it is often due to selection, as in human red lips.

Overwhelmingly, the most common function of colour is in predator-prey relationships. "Anti-predator adaptations occur in every biome of the world and in almost every taxonomic group".

Animal colour has been a topic of interest and research in biology for a long time. According to Charles Darwin's 1859 theory of natural selection, features such as colouration evolved by providing individual animals with a reproductive advantage. For example, individuals with slightly better camouflage than others of the same species would, on average, leave more offspring.

Startle and dazzle defences

Animals can have a camouflage defence at distance, but when faced by a predator they may switch to a 'flash' defence to gain time and distract the predator. The predator often blinks or turns its face away in self-defence. This is a reflex act which is there to protect its vital facial area. In the second the predator blinks, the prey flies or jumps, and lands in camouflage again. This pattern of colour plus behaviour is quite common. It is called deimatic defence by textbooks, from the Greek for 'dread' or 'to frighten'.

Related pages

• Camouflage
• Defence against predators
• Mimicry
• Sexual dimorphism
• Warning colouration

Images for kids

• 

  Bright coloration of orange elephant ear sponge, Agelas clathrodes signals its bitter taste to predators

• 

  Robert Hooke's Micrographia

• 

  Warning coloration of the skunk in Edward Bagnall Poulton's The Colours of Animals, 1890

• 

  In Roseate Spoonbills 1905–1909, Abbott Handerson Thayer tried to show that even the bright pink of these conspicuous birds had a cryptic function.

• 

  A camouflaged orange oak leaf butterfly, Kallima inachus (centre) has protective resemblance.

• 

  A flower mantis, Hymenopus coronatus, uses special Aggressive mimicry.

• 

  Cleaner wrasse signals its cleaning services to a big eye squirrelfish

• 

  A venomous coral snake uses bright colours to warn off potential predators.

• 

  The black and yellow warning colours of the cinnabar moth caterpillar, Tyria jacobaeae, are instinctively avoided by some birds.

• 

  The hawk-cuckoo resembles a predatory shikra, giving the cuckoo time to lay eggs in a songbird's nest unnoticed

• 

  A praying mantis in deimatic or threat pose displays conspicuous patches of colour to startle potential predators. This is not warning coloration as the insect is palatable.

• 

  This frog changes its skin colour to control its temperature.

• 

  The olm's blood makes it appear pink.

• 

  Side of zebrafish shows how chromatophores (dark spots) respond to 24 hours in dark (above) or light (below).

• 

  The red pigment in a flamingo's plumage comes from its diet of shrimps, which get it from microscopic algae.

• 

  Squid chromatophores appear as black, brown, reddish and pink areas in this micrograph.

• 

  The brilliant iridescent colours of the peacock's tail feathers are created by Structural coloration.

• 

  Butterfly wing at different magnifications reveals microstructured chitin acting as diffraction grating.

• 

  A Euplokamis comb jelly is bioluminescent.

See also

In Spanish: Coloración animal para niños