BEHAVIOR | Sex and the Single Bowerbird
How do extreme displays of male behavior evolve? While there's still no clear answer, the search for one has spawned a rich variety of studies on sexual selection. Using animatronics, one team is helping to explain how females choose males and why different females make different choices.
Gerald Borgia and his University of Maryland colleagues are investigating the complex displays of 11 male bowerbird species in the Australasian region. These males do not parent, but build finely crafted stick structures, or bowers, and decorate display courts when they want to mate (G. Borgia, "Why do bowerbirds build bowers?" Am Sci, 85:542-7, 1995). Team member Gail Patricelli has built a lifelike female bowerbird robot that performs convincing courtship movements to show that females are not passive players.
Field videos and sound recordings show that males aggressively compete and that the quality of bowers and ...
