Signalling with a cryptic trait

Abstract

Sexual signals often compromise camouflage because of their conspicuousness. Pigmentation patterns, on the contrary, aid in camouflage. It was hypothesized that a particular type of pattern—barred plumage in birds, whereby pigmented bars extend across feathers—could simultaneously signal individual quality, because disruptions of these patterns should be perceptually salient at close range and help assess plumage condition.