The evolution of vocal duets and migration in New World warblers (Parulidae)

Abstract

Vocal duets occur when 2 individuals vocalize in temporal coordination. In birds, duet participation functions to cooperatively defend shared resources, localize mates, and in some species, guard the mate. Previous work indicates that duetting tends to co-evolve with a non-migratory lifestyle, probably because the absence of migration facilitates greater cooperation between mates. We examined the evolution of duetting and migration in New World warblers (Parulidae), a group that has been largely ignored by duetting research. Of the 95 species in our analysis, we found evidence of duetting in 19 (20%) species, and evidence of migration in 45 (47.4%) species. Ancestral character reconstruction indicated that the last common ancestor of the New World warblers did not duet. Duetting evolved multiple times in this group, including 2 early origins and several more recent origins. Migration was present in the last common ancestor and was lost several times. Both duetting and migration exhibit phylogenetic signal. A phylogenetically explicit correlation analysis revealed a significant negative relationship between duetting and migration, in keeping with findings from other avian taxa. This study, the first description of the evolution of duetting in a large avian family with a temperate-zone origin, supports the hypothesis that duetting co-evolves with a sedentary natural history in birds.

Behavioral, morphological, and ecological trait evolution in two clades of New World Sparrows (AimophilaandPeucaea, Passerellidae)

“…Work on the genera Melozone and Peucaea has demonstrated that duets of different species have similar functions in resource defense, providing a possible selective pressure maintaining this trait (Benedict, 2010;Sandoval, Méndez & Mennill, 2013;Illes, 2015;Sandoval, Juárez & Villarreal, 2018). Similarly, studies of other New World avian clades have shown that vocal duet presence and form are often evolutionarily conserved (Mann et al, 2009;Mitchell et al, 2019). This pattern is likely driven by life-history traits such as monogamy, territoriality, and sedentariness, which are shown by many of the species included in our analysis (Benedict, 2008;Logue & Hall, 2014).…”

Morphological traits influence prey selection by coexisting species of New World warblers (Parulidae)

“…Our results indicate that, in addition to these dramatic species differences potentially linked to sexual selection and other life-history traits (e.g., Mitchell et al 2019), parulids also differ significantly in external morphological traits relevant to foraging behavior. The nature of these predictions, linked directly to foraging behavior (e.g., for larger insects and for flying versus non-flying insects), help explain the kinds of foraging differences among coexisting insectivorous birds that past authors interpreted as coexistence mechanisms (e.g., MacArthur 1958, Morse 1989, Mansor et al 2018.…”

Peer Review #2 of "Behavioral, morphological, and ecological trait evolution in two clades of New World Sparrows (Aimophila and Peucaea, Passerellidae) (v0.1)"

“…For this study, we followed Wolf (1977) in defining song complexity based on the number and variety of note types in the species-typical song. Although debate exists about what metrics of song best describe "complexity" (Pearse et al, 2018;Najar & Benedict, 2019;Benedict & Najar, 2019), increased complexity reflects higher syllable diversity in the species we studied and is conserved in related lineages. This result might suggest that closely related species are under similar selective pressures for maintenance of song structure, potentially relating to visual signaling or habitat as discussed above (Panhuis et al, 2001;Boncoraglio & Saino, 2007).…”

“…Work on the genera Melozone and Peucaea has demonstrated that duets of different species have similar functions in resource defense, providing a possible selective pressure maintaining this trait (Benedict, 2010;Illes, 2015;Sandoval et al, 2018). Similarly, studies of other New World avian clades have shown that vocal duet presence and form are often evolutionarily conserved (Mann et al, 2009;Mitchell et al, 2019). This pattern is likely driven by life-history traits such as monogamy, territoriality, and sedentariness, which are shown by many of the species included in our analysis (Benedict, 2008;Logue & Hall, 2014).…”