Short answers, pulled from the story.
Camouflage is the use of any combination of materials, coloration, or illumination to conceal animals or objects, either by making them hard to see or by disguising them as something else. Methods include background matching, disruptive coloration, countershading, transparency, silvering, mimesis, and motion dazzle, and may be applied alone or in combination.
In his 1859 Origin of Species, Darwin cited the alpine ptarmigan white in winter and the red grouse the colour of heather as evidence that animal coloration provides a survival advantage under natural selection. He argued that hawks guided by eyesight to their prey make camouflage a direct determinant of whether prey species survive to reproduce.
The marine artist Norman Wilkinson devised dazzle camouflage in April 1917, when German U-boats were sinking large numbers of British ships with torpedoes. In his own words, dazzle was designed not for low visibility, but to break up a ship's form and confuse a submarine officer as to the course on which she was heading.
Pablo Picasso reportedly connected the first camouflaged truck he saw in Paris around 1915 directly to cubism. In 1919 the Chelsea Arts Club hosted a dazzle ball at the Albert Hall in dazzle-patterned clothing, spreading the aesthetic through postcards and magazine articles. Andy Warhol began a series of monumental camouflage paintings in 1986, and New York designer Stephen Sprouse used them as the basis for his Autumn Winter 1987 collection.
The Agouti genes are orthologous genes involved in camouflage across many lineages, producing yellow and red coloration in competition with genes that produce black and brown colours. In eastern deer mice, a single agouti gene developed nine mutations over roughly 8,000 years that each strengthened expression of yellow fur under natural selection.
CADPAT, the Canadian Disruptive Pattern, was the first genuinely digital camouflage pattern and was issued to the Canadian army in 2002. The American Marine pattern MARPAT followed shortly after. These pixellated designs provide a fractal-like range of patch sizes so they appear disruptively coloured both at close range and at a distance.