ANIMAL APPEARANCE IMAGES

Pink painters We traditionally associate flamingos with the colour pink, but they vary from a whitish pink to a more vivid one. Researchers in Spain have found that flamingos produce an oil from their glands that causes a temporary pink stain, and that in mating season they apply this oil to their feathers. CC BY NC ND Clara S/Flickr

BIGPICTUREEDUCATION.COM Chameleons can take on a number of different colour combinations. Although it’s commonly thought they do this to blend in with a background, it’s more often done to regulate body temperature and communicate with other chameleons in conflict or potential mating situations. CC BY NC Steve Wilson, pokerbrit/Flickr Chameleon communication

BIGPICTUREEDUCATION.COM Some bottom-feeding fish do change colour to blend in with their surroundings, however – and this often done so as not to alert potential prey. Some fish, such as the peacock flounder, even move the location of their eyes as they age. If its eyes are damaged, the fish may struggle to change colour. CC BY NC Steve Jurvetson/Flickr Fishing for food

BIGPICTUREEDUCATION.COM This clever creature is able to mimic the appearance of other organisms by changing colour, texture and shape. The primary reason for this seems to be to avoid predators. The mimic octopus has been documented imitating lionfish, sea snakes, flatfish and jellyfish – many of which are poisonous. CC BY NC Prilfish/Flickr Imitating octopi

Chimpanzee copulation BIGPICTUREEDUCATION.COM Primates also change their appearance in certain cases. The genitals of the female chimpanzee inflate to a very large size and turn a vivid pink at the height of her menstrual cycle, an unmissable visual sign to potential suitors. CC BY NC ND Angi English/Flickr

BIGPICTUREEDUCATION.COM Some birds change colour when they are particularly unwell. One example is the grey cockatiel, whose white feathers – and sometimes even its grey ones – turn yellow if it has liver disease. CC BY NC ND Jes/Flickr Feather affliction

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