Coevolutionary maintenance of forked tails and song in hirundines (Aves: Hirundininae)

Both conspicuous plumage ornamentation and song are well‐known examples of sexually selected traits, but their interrelationship is not well known, perhaps in part because confounding factors, including interspecific variation ecology, habitat, morphology, type ornamentation. Here, using a phylogenetic comparative approach the 69 species with available information (i.e. 96% all 72 species), I examined evolutionary relationship between forked tails presence/absence hirundines (Aves: Hirundininae). Hirundines have similar ecology (e.g. aerial insectivores, social monogamy, biparental provisioning), morphology syrinx nearly complete bronchial rings), tail), which provides unique opportunity to examine associations song. In particular, repeatedly lost ornamentation, tails, setting up condition test association gain/loss simple After controlling for phylogeny covariates, demonstrated that was less likely be found forkless than tails. Two correlates tail shape, sexual dimorphism overall characteristics as proxy selection incubation measure extrapair mating opportunity, were positively related presence or absence song, indicating importance rather correlates. The analysis correlated evolution discrete characters further supported two maintained together under each other. current study provided macroevolutionary support integrated use visual acoustic courtship traits.