A global analysis of aerial displays in passerines revealed an effect of habitat, mating system and migratory traits

Abstract

Aerial displaying is a flamboyant part of the sexual behaviour of several volant animal groups, including birds. Nevertheless, little attention has been focused on identifying correlates of large-scale diversity in this trait. In this study, we scored the presence and absence of aerial displays in males of 1732 species of passerine birds (Passeriformes) and employed Bayesian phylogenetically informed mixed models to test for associations between aerial displays and a set of life-history and environmental predictors. Our multi-variate models revealed that species with males that perform aerial displays inhabited open rather than closed (forested) habitats. These species also exhibited higher levels of polygyny, had more elongated wings, migrated over longer distances and bred at higher latitudes. When we included species where the sexual function of displays has not been explicitly described but is likely to occur, we found that aerial displaying was also associated with smaller body size and increased male plumage coloration. Our results suggest that both sexual selection and natural selection have been important sources of selection on aerial displays in passerines.

Response of pollinator taxa to fire is consistent with historic fire regimes in the Sierra Nevada and mediated through floral richness†

“…Meadows provide an abundance of floral resources, with higher average diversity and cover than upland habitats (Figure A2), making these resources easier to find in meadows (Dávalos & Blossey, 2011). Additionally, pollinators may be particularly attracted to meadow habitats because they provide abundant host plants (van Nouhuys & Hanski, 2005), opportunities for mud puddling (Downes, 1973), increased visibility for mate‐seeking (Dennis & Shreeve, 1988), courtship displays (Mikula et al., 2022), and higher light levels for flight (Ross et al., 2005). For example, caterpillars of many butterfly species are dependent on particular host species or genera, which are often associated with or limited to mesic habitats (Dennis & Shreeve, 1988; Fleishman, 2000).…”

Maneuverable flight evolved with forked tails and opportunities for extrapair mating in swallows and martins (Aves: Hirundininae)

“…4). Some flight performance is known to evolve with sexual selection, particularly when used as courtship display (e.g., aerial display found in polygynous birds; e.g., Mikula et al 2022). It is thus not surprising that our measures of flight performance evolved with an index of opportunities of extrapair mating, even when we evaluated daily flight performance (see Methods).…”