Diversity in mimicry: paradox or paradigm?

Visual mimicry is a textbook case of natural selection because it is both intuitively understandable and has repeatedly evolved in a range of organisms: it is the ultimate example of parallel evolution. In many mimetic groups, particularly butterflies, a huge variety of colour patterns has arisen, even in closely related species. There has been much recent controversy over explanations of this variety. Mimicry is today a broad field of evolutionary study; here we discuss the evolution of its diversity in predator-prey systems.