In biology, what 3-letter word derived from the Swedish for 'play' is a gathering of males of certain bird species for the purposes of mating display?
Bird-of-paradise lek-type mating system. Others, such as the "Cicinnurus" and "Parotia" species, have highly ritualised mating dances. Males are polygamous in the sexually dimorphic species, but monogamous in at least some of the monomorphic species. Hybridisation is frequent in these birds, suggesting the polygamous species of bird of paradise are very closely related despite being in different genera. Many hybrids have been described as new species, and doubt remains regarding whether some forms, such as Rothschild's lobe-billed bird of paradise, are valid. Birds-of-paradise build their nests from soft materials, such as leaves, ferns, and vine tendrils, typically placed in a tree
Assortative mating can arise as a consequence of intrasexual competition. In some species, size is correlated with fecundity in females. Therefore, males choose to mate with larger females, with the larger males defeating the smaller males in courting them. Examples of species that display this type of assortative mating include the jumping spider "Phidippus clarus" and the leaf beetle "Diaprepes abbreviatus". In other cases, larger females are better equipped to resist male courtship attempts, and only the largest males are able to mate with them. Assortative mating can, at times, arise as a consequence of social competition. Traits in certain individuals may