Occurrence and life history correlates of vocal duetting in North American passerines

Abstract

Vocal duetting, where two birds produce temporally coordinated vocalizations, has been reported in a taxonomically and geographically diverse set of avian species. Researchers have suggested a number of potential correlates of duetting, including long term monogamy, year-round territory defense and sexual plumage monomorphism. Because the majority of duetting species are tropical, they have been the focus of the most comprehensive studies to date. There is, therefore, a real need for data regarding avian duets in temperate species. I used the recently completed Birds of North America species reports to examine the frequency, evolutionary origins and potential life history correlates of duetting behavior in North American passerines. ''Duetting'' behavior was reported in 7% of species from 12 avian families, likely representing 17 separate evolutionary origins. Duetting species showed apparent long term monogamy and year-round territoriality at frequencies more than double those of non-duetting passerines: 65% of duetting species were long term monogamous, compared to 27% of non-duetting species, and 50% of duetting species defended the same territory throughout the year, compared with only 11% of non-duetting species. Duetting and non-duetting species showed statistically indistinguishable frequencies of sexual plumage monomorphism. Comparative analyses of duetting species and their sister taxa revealed that the shift to duetting is accompanied by a gain of long term monogamy and year-round territoriality more often than it is associated with a loss of those traits. This study provides intriguing summary evidence that selective factors promoting duetting may be associated with a sedentary, monogamous lifestyle, and may operate similarly across taxonomic groups. Furthermore, vocal duetting may be considerably more common among temperatezone species than previously recognized.

Migration and the evolution of duetting in songbirds

“…Consistent with this functional interpretation, there are positive associations between duetting and both pair-bond duration and year-round territoriality in North American birds [10]. Avian duets are thought to be more common in the tropics [11,12], and may be associated with sexual monochromatism [12,13] (but see [10,11]). Conclusions about the evolution of duetting based on existing comparative analyses are limited by the scopes and methodologies of those studies.…”

Female Song in New World Wood-Warblers (Parulidae)

“…Species that are territorial year-round or that maintain a pair bond through the winter are exactly the sort of species we would predict to have female song (Benedict, 2008;Price, 2009). While most Neotropical migrants do not seem to be territorial in the winter, some, such as Leiothlypis peregrina (Birds of North America), hold winter territories, and are thus territorial year-round.…”

“…A recent surge of interest in this topic has supported the idea that female song is associated with life-history traits that are common in tropical areas, including yearround territoriality and/or non-migratory behavior, sexual monochromatism, carotenoid dichromatism, and monogamy (Malacarne et al, 1991;Garamszegi et al, 2007;Benedict, 2008;Price, 2009;Price et al, 2009;Logue and Hall, 2014). In particular, gain of migratory behavior is strongly correlated with loss of female song (including duetting; Price et al, 2009;Logue and Hall, 2014).…”

“…Following the hypothesis that non-migratory, monogamous species with similar sex roles are more likely to express female song (Morton, 1996;Benedict, 2008;Price, 2009), we predicted that gains of female song in warblers would be strongly correlated with losses of migration and losses of dichromatic plumage.…”

Impact of visual contact on vocal interaction dynamics of pair-bonded birds

“…Some species even exhibit highly synchronized vocal duets 60 between mates (Benedict, 2008;Dahlin & Benedict, 2013;Farabaugh, 1982;Hall, 2004Hall, , 2009.…”