Paul Schwartz and David W. Snow, "Display and Related Behavior of the Wire-Tailed Manakin," The Living Bird Seventeenth Annual of the Cornell Laboratory of Ornithology, 1978


This is the name we gave to the display that answered the long-asked question: what is the function of the tail filaments? The answer astonished both of us. The filaments are not for visual display as had been thought; at least, not primarily. They are tactile organs of a quite unique kind: with them one bird brushes the other on the face or throat.

For its full realization the Twist requires two cooperating birds, one of them active, the other passive. Starting from a Stationary Display, which may be held only momentarily, the active bird further lowers its head, raises its tail, and with vibrating wings begins to pivot or twist its body fairly rapidly from side to side across the perch through an angle of about 60 degrees, sometimes more. It is oriented facing away from its partner. Slowly it hitches along the perch, with jerky backward movements, at the same time increasing the tempo of its twisting and raising its tail even more. The partner, who is perched normally, edges toward the active bird. When the birds approach closely enough there is physical contact; in its whipping back and forth, the twisting bird's tail brushes the partner rhythmically.... In a well-coordinated display session, male partners alternate the active and passive roles.

(Drawing by Dana Gardner)