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Many species of socially monogamous birds engage in extra-pair copulations, but the extent of extra-pair paternity varies considerably by species. The ecological conditions contributing to interspecific variation in rates of extra-pair paternity remain unclear. We used a combination of single-nucleotide polymorphisms and microsatellites to document extra-pair paternity in the Banded Wren (Thryothorus pleurostictus), a socially monogamous neotropical passerine that lives in a highly seasonal environment. The rate of extra-pair paternity was relatively low, with extra-pair males siring 4% of offspring in 10% of nests. This low rate is consistent with current hypotheses predicting low rates of extra-pair paternity in nonmigratory species in which survivorship of adults is high, and it is contrary to the pattern predicted by hypotheses linking synchronous breeding with high rates of extra-pair paternity. Extra-pair males sang better and were more genetically similar to females than the males they cu...

Secondary contact between closely related species can lead to hybridization. The fitness of hybrid individuals within and outside the hybrid zone determines whether the hybrid zone expands into the ranges of the 2 parental species or remains a stable, geographically narrow area in between the allopatric ranges of the parental species. In birds, vocalizations play an important role in male‐male competition and female mate choice and are often affected by hybridization. One of the factors that will influence male hybrid fitness is the ability to defend a territory against competitors by vocalizing. We tested the efficacy of territorial signals of hybrids of 2 dove species, Streptopelia vinacea and Streptopelia capicola, compared with the vocalizations of the parental species. With playback experiments, we assessed the response to hybrid and the 2 parental species vocalizations in the hybrid zone and adjacent allopatric populations of each species. In the hybrid zone, males did not respond differently to the 3 vocalization types. In both allopatric populations, however, males responded more to conspecific than to heterospecific signals and the response strength to hybrid signals was intermediate. Therefore, in the allopatric populations, hybrid males may have a reduced success in defending territories. In male‐male interactions in the hybrid zone, hybrids may not have a disadvantage compared with males of the parental species. The ability to defend a territory against competitors may thus help maintain a stable hybrid zone in the area of overlap. Key words: acoustic signals, hybrid zone, playback, song, Streptopelia doves, territorial interactions. [Behav Ecol]

Some of the 16 dove species in the genus Streptopelia are very similar with respect to plumage pattern, but all seem to produce species-specific perch-coo vocalizations. Here, we describe variation in perch-coo recordings of all 16 species. All individuals could be correctly classified by species in a discriminant function analysis, which means that the overlap in inter- and intraspecific variation was limited for the total set of acoustic parameters. Interspecific similarity in acoustic parameters was compared with taxonomic classification, based upon qualitative morphological characteristics and geographic distribution (Goodwin 1983). The clustering of species using the acoustic data set showed little congruence with taxonomic clustering. This indicates that differentiation in plumage pattern does not necessarily coincide with differentiation in acoustic characteristics. However, our analysis did not Completely contradict the subdivision into four taxonomic groups based on morphology and distribution. Two of the four putative groups differed significantly from the other groups in one of the components of a principal components analysis. Vocal differentiation in Streptopelia doves was strongest in temporal components, which is in line with expectations based on the evolutionarily conservative syringeal constraints.