Editing Camouflage (section)

== History ==

=== Classical antiquity ===

[[File:Octopus cyaneain Kona.jpg|thumb|upright=0.8|Octopuses like this ''[[Octopus cyanea]]'' can change colour (and shape) for camouflage]]

In ancient Greece, [[Aristotle]] (384–322 BC) commented on the colour-changing abilities, both for camouflage and for [[Signalling theory|signalling]], of [[cephalopod]]s including the octopus, in his ''[[Historia animalium]]'':<ref name=Aristotle>Aristotle (c. 350 BC). ''Historia Animalium''. IX, 622a: 2–10. Cited in Borrelli, Luciana; [[Francesca Gherardi|Gherardi, Francesca]]; Fiorito, Graziano (2006). ''A catalogue of body patterning in Cephalopoda''. Firenze University Press. {{ISBN|978-88-8453-377-7}}. [http://www.fupress.com/scheda.asp?IDV=487 Abstract] {{Webarchive|url=https://web.archive.org/web/20180206145302/http://classics.mit.edu/Aristotle/history_anim.9.ix.html |date=6 February 2018 }}</ref>

{{blockquote|The [[octopus]]&nbsp;... seeks its prey by so changing its colour as to render it like the colour of the stones adjacent to it; it does so also [[Deimatic behaviour|when alarmed]].|Aristotle<ref name=Aristotle/>}}

=== Zoology ===

Camouflage has been a topic of interest and research in [[zoology]] for well over a century. According to [[Charles Darwin]]'s 1859 theory of [[natural selection]],{{sfn|Darwin|1859}} features such as camouflage [[evolution|evolved]] by providing individual animals with a reproductive advantage, enabling them to leave more offspring, on average, than other members of the same [[species]]. In his ''[[Origin of Species]]'', Darwin wrote:{{sfn|Darwin|1859|page=84}}

{{blockquote|When we see leaf-eating insects green, and bark-feeders mottled-grey; the alpine ptarmigan white in winter, the [[red grouse|red-grouse]] the colour of [[Calluna vulgaris|heather]], and the [[black grouse|black-grouse]] that of [[peat]]y earth, we must believe that these tints are of service to these birds and insects in preserving them from danger. Grouse, if not destroyed at some period of their lives, would increase in countless numbers; they are known to suffer largely from [[birds of prey]]; and hawks are guided by eyesight to their prey, so much so, that on parts of the Continent persons are warned not to keep white pigeons, as being the most liable to destruction. Hence I can see no reason to doubt that natural selection might be most effective in giving the proper colour to each kind of grouse, and in keeping that colour, when once acquired, true and constant.{{sfn|Darwin|1859|page=84}}}}

[[File:Variable Protective Resemblance in Lepidopterous Pupae.jpg|thumb|left|upright=1.35|Experiment by [[Edward Bagnall Poulton|Poulton]], 1890: [[Ourapteryx sambucaria|swallowtailed moth]] [[pupa]]e with camouflage they acquired as [[larva]]e]]

The English zoologist [[Edward Bagnall Poulton]] studied [[animal coloration]], especially camouflage. In his 1890 book ''[[The Colours of Animals]]'', he classified different types such as "special protective resemblance" (where an animal looks like another object), or "general aggressive resemblance" (where a predator blends in with the background, enabling it to approach prey). His experiments showed that [[swallow-tailed moth]] [[pupae]] were camouflaged to match the backgrounds on which they were reared as [[larvae]].{{sfn|Poulton|1890|page=111}}{{efn|A letter from [[Alfred Russel Wallace]] to Darwin of 8 March 1868 mentioned such colour change: "Would you like to see the specimens of pupæ of butterflies whose colours have changed in accordance with the colour of the surrounding objects? They are very curious, and Mr. [[T. W. Wood]], who bred them, would, I am sure, be delighted to bring them to show you."<ref>{{cite web |last=Wallace |first=Alfred Russel |author-link=Alfred Russel Wallace |url=http://darwin-online.org.uk/content/frameset?pageseq=1&itemID=F1592.1&viewtype=text |title=Alfred Russel Wallace Letters and Reminiscences By James Marchant |publisher=Darwin Online |date=8 March 1868 |access-date=29 March 2013}}</ref>}} Poulton's "general protective resemblance"{{sfn|Poulton|1890|page=Fold-out after p. 339}} was at that time considered to be the main method of camouflage, as when [[Frank Evers Beddard]] wrote in 1892 that "tree-frequenting animals are often green in colour. Among vertebrates numerous species of [[parrot]]s, [[iguana]]s, [[tree frog|tree-frogs]], and the [[Morelia viridis|green tree-snake]] are examples".{{sfn|Beddard|1892|page=83}} Beddard did however briefly mention other methods, including the "alluring coloration" of the [[Hymenopus bicornis|flower mantis]] and the possibility of a different mechanism in the [[Anthocharis cardamines|orange tip butterfly]]. He wrote that "the scattered green spots upon the under surface of the wings might have been intended for a rough sketch of the small flowerets of the plant [an [[umbellifer]]], so close is their mutual resemblance."{{sfn|Beddard|1892|page=87}}{{efn|Cott explains Beddard's observation as a coincident disruptive pattern.{{sfn|Cott|1940|pages=74–75}}}} He also explained the coloration of sea fish such as the [[mackerel]]: "Among [[pelagic]] fish it is common to find the upper surface dark-coloured and the lower surface white, so that the animal is inconspicuous when seen either from above or below."{{sfn|Beddard|1892|page=122}}

[[File:PeacockInTheWoods.jpg|thumb|upright|[[Abbott Thayer]]'s 1907 painting ''Peacock in the Woods'' depicted a [[peacock]] as if it were camouflaged.]]

The artist [[Abbott Handerson Thayer]] formulated what is sometimes called Thayer's Law, the principle of [[countershading]].{{sfn|Thayer|1909}} However, he overstated the case in the 1909 book ''[[Concealing-Coloration in the Animal Kingdom]]'', arguing that "All patterns and colors whatsoever of all animals that ever preyed or are preyed on are under certain normal circumstances obliterative" (that is, cryptic camouflage), and that "Not one '[[mimicry]]' mark, not one '[[aposematism|warning color]]'...&nbsp;nor any '[[sexual selection|sexually selected]]' color, exists anywhere in the world where there is not every reason to believe it the very best conceivable device for the concealment of its wearer",{{sfn|Forbes|2009|page=77}}{{sfn|Thayer|1909|pages=5, 16}} and using paintings such as ''Peacock in the Woods'' (1907) to reinforce his argument.{{sfn|Rothenberg|2011|pages=132–133}} Thayer was roundly mocked for these views by critics including [[Theodore Roosevelt|Teddy Roosevelt]].<ref>{{cite journal |last1=Wright |first1=Patrick |title=Cubist Slugs. Review of DPM: Disruptive Pattern Material; An Encyclopedia of Camouflage: Nature – Military – Culture |journal=[[London Review of Books]] |date=23 June 2005 |volume=27 |issue=12 |pages=16–20 |url=http://www.lrb.co.uk/v27/n12/patrick-wright/cubist-slugs |archiveurl=https://web.archive.org/web/20200402143133/https://www.lrb.co.uk/the-paper/v27/n12/patrick-wright/cubist-slugs|archivedate=2 April 2020}}</ref>

The English zoologist [[Cott, H. B.|Hugh Cott]]'s 1940 book ''[[Adaptive Coloration in Animals]]'' corrected Thayer's errors, sometimes sharply: "Thus we find Thayer straining the theory to a fantastic extreme in an endeavour to make it cover almost every type of coloration in the animal kingdom."{{sfn|Cott|1940|pages=172–173}} Cott built on Thayer's discoveries, developing a comprehensive view of camouflage based on "maximum disruptive contrast", countershading and hundreds of examples. The book explained how [[disruptive camouflage]] worked, using streaks of boldly contrasting colour, paradoxically making objects less visible by breaking up their outlines.{{sfn|Cott|1940|pages=47–67}} While Cott was more systematic and balanced in his view than Thayer, and did include some experimental evidence on the effectiveness of camouflage,{{sfn|Cott|1940|pages=174–186}} his 500-page textbook was, like Thayer's, mainly a [[natural history]] narrative which illustrated theories with examples.{{sfn|Forbes|2009|pages=153–155}}

Experimental evidence that camouflage helps prey avoid being detected by [[predator]]s was first provided in 2016, when ground-nesting birds ([[plovers]] and [[coursers]]) were shown to survive according to how well their egg contrast matched the local environment.<ref name="TrosciankoWilson-AggarwalStevensSpottiswoode2016">{{cite journal |last1=Troscianko |first1=Jolyon |last2=Wilson-Aggarwal |first2=Jared |last3=Stevens |first3=Martin |author3-link=Martin Stevens (biologist) |last4=Spottiswoode |first4=Claire N. |title=Camouflage predicts survival in ground-nesting birds |journal=Scientific Reports |volume=6 |issue=1 |date=29 January 2016 |doi=10.1038/srep19966 |pmid=26822039 |pmc=4731810 |page=19966 |bibcode=2016NatSR...619966T }}</ref>