Variation in the colour and patterning of animal coats has evolved to offer individuals adaptive advantage and is determined by both genetics and environmental factors. The biological functions of animal coat patterns include protection of the skin from exposure to sunlight, protection from predators by camouflage, individual recognition and sexual recognition within a species. Optimal coat patterns are especially important in the wild where immediate survival relies on an individual’s ability to avoid predators. Changes in coat colour within an individual may be attributable to external variables such as temperature, seasonal changes in day length and light, or internal variables such as testosterone and melatonin levels, and age.
