London: Methuen Publishing, 1957. — 508 p.
Reprinted with minor corrections from edition 1940.Among a certain section of experimental biologists, any time in these last thirty years, it has been fashionable and indeed almost a matter of professional conscience to display a radical scepticism on the subject of adaptations, especially colour adaptations, and most particularly mimetic adaptations. Upholders of the theories of protective and warning coloration and of mimicry have often been attacked as 'armchair theorists' (whereas they have in fact almost invariably been first and foremost field naturalists), insufficiently acquainted with modern work in genetics, which for some unexplained reason is held to do away with adaptive interpretations.
