Practice question

Resemblance among unpalatable butterfly species accelerates predator education because each encounter reinforces the same warning signal. A bird that samples one defended species and experiences bitterness, nausea, or another cost can generalize avoidance to other species bearing the shared pattern. Consequently, fewer individuals of each species need to be attacked before the local predator population learns, reducing the per-species cost of establishing warning. This is the central advantage of Müllerian mimicry. The effect is more precise than simply “confusing” predators: successful warning systems promote rapid recognition and a consistent decision not to attack. Attraction of mates is not the primary interspecific benefit, although wing patterns can also participate in sexual recognition. Hiding from prey is irrelevant because the conspicuous pattern targets predators. The strength of the benefit depends on predator memory, relative abundance, degree of pattern similarity, and the defenses’ severity. Convergence can therefore be favored by positive frequency-dependent selection, as common warning phenotypes are learned more reliably than rare alternatives.