Date: November 20, 2018
Source: Cornell University
Male birds-of-paradise are justly world famous for their wildly extravagant feather ornaments, complex calls, and shape-shifting dance moves -- all evolved to attract a mate. New research published in the open-access journal PLOS Biology suggests for the first time that female preferences drive the evolution of physical and behavioral trait combinations that may also be tied to where the male does his courting: on the ground or up in the trees. There are 40 known species of birds-of-paradise, most found in New Guinea and northern Australia.
Study lead author Russell Ligon, a postdoctoral researcher at the Cornell Lab of Ornithology, suggests females are evaluating not only how great the male looks but, simultaneously, how well he sings and dances. Female preferences for certain combinations of traits result in what the researchers call a "courtship phenotype" -- bundled traits determined by both genetics and environment.
Study authors examined 961 video clips and 176 audio clips in the Cornell Lab's Macaulay Library archive as well as 393 museum specimens from the American Museum of Natural History in New York City. They conclude that certain behaviors and traits are correlated: