Hiding in plain view

Camouflage is essential for any prey and evolution has provided that mysterious sleight of hand ability to many successful herbivorous species. Some of these tricks would be the envy of the best of magicians. Yet, the camouflage cannot be so good that communication is stilled within the species, limiting social interactions such as courting and mating. Consider the bullethead parrotfish (Chlorurus sordidus) on this month’s cover as it uses the technique of pointillism to hide in plain view at a predatorial distance and yet keeps its harem in order at a closer distance.

Pointillism is a technique in painting whereby small dots of “pure” colours are used to create an overall effect of “blended” colours when viewed from the proper distance. Theoretically, the technique would increase luminosity to achieve an optical blending at the retinal level. This artistic idea was demonstrated by Georges Seurat in 1884 in his painting “A Sunday Afternoon on the Island of the Grand Jatte.” He was not, however, the first nor the last to utilise this principle. The technique relies upon the concept of receptive fields although the …