Problems of display postures in the Charadrii (Aves: Charadriiformes)
Studies of displays in the Charadrii (= waders or shorebirds) show that the same posture in different species, even quite closely related, may have a different function in a given context. As a corollary to this, two species even in the same genus may have quite different display postures to convey the same message. The problem is thus twofold: (a) to interpret the function of the display in the bird's world and (b) to trace the evolution of the display within a single well-defined suborder of birds such as the Charadrii. Threat displays are especially informative in such studies, but courtship, distraction and other displays are also useful. The value of display postures in the systematics of the waders is discussed.