In attracting mates, male bowerbirds appear to rely on special optical effect

Bowerbird males are well known for making elaborate constructions, lavished with decorative objects, to impress and attract their mates. Now, researchers reporting online on September 9 in Current Biology have identified a completely new dimension to these showy structures in great bowerbirds. The birds create a staged scene, only visible from the point of view of their female audience, by placing pebbles, bones, and shells around their courts in a very special way that can make objects (or a bowerbird male) appear larger or smaller than they really are.