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Animal camouflage provides some of the most striking examples of the workings of natural selection, whether employed defensively to reduce predation risk, or offensively to minimise alerting prey. While the general benefi ts of camouflage are obvious, understanding the precise means by which the viewer is fooled represent a challenge to a biologist, because camouflage is an adaptation to the eyes and mind of another animal. Therefore, a full understanding of the mechanisms of camoufl age requires an interdisciplinary investigation of the perception and cognition of non-human species, involving the collaboration of biologists, neuroscientists, perceptual psychologists and computer scientists. Modern computational neuroscience grounds the principles of Gestalt psychology, and the intuition of generations of artists, in specific mechanisms that can be tested. We review the various forms of animal camoufl age from this perspective, illustrated by the recent upsurge of experimental studies of long-held, but largely untested, theories of defensive colouration.
animal colouration, antipredator behaviour, camoufl age, colour vision, crypsis, defensive colouration
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