Low level of extra-pair paternity between nearest neighbors results from female preference for high-quality males in the yellow-rumped flycatcher (Ficedula zanthopygia)

Abstract

Extra-pair copulation is considered to be a means by which females can modify their initial mate choice, and females might obtain indirect benefits to offspring fitness by engaging in this behavior. Here, we examined the patterns of extra-pair paternity and female preferences in the yellow-rumped flycatcher (Ficedula zanthopygia). We found that female yellow-rumped flycatchers are more likely to choose larger and relatively highly heterozygous males than their social mates as extra-pair mates, that the genetic similarity of pairs that produced mixed-paternity offspring did not differ from the similarity of pairs producing only within-pair offspring, and that extra-pair offspring were more heterozygous than their half-siblings. These findings support the good genes hypothesis but do not exclude the compatibility hypothesis. Most female yellow-rumped flycatchers attained extra-pair paternity with distant males rather than their nearest accessible neighboring males, and no differences in genetic and phenotypic characteristics were detected between cuckolded males and their nearest neighbors. There was no evidence that extra-pair mating by female flycatchers reduced inbreeding. Moreover, breeding density, breeding synchrony and their interaction did not affect the occurrence of extra-pair paternity in this species. Our results suggest that the variation in extra-pair paternity distribution between nearest neighbors in some passerine species might result from female preference for highly heterozygous males.

Divorce is linked with extra-pair paternity in a monogamous passerine

“…Accordingly, the number (Oh and Badyaev 2010;Dunning et al 2023) and quality (Firth and Sheldon 2016;Beck, Farine, and Kempenaers 2021) of social associations were empirically shown to be linked to reproductive success, including extra-pair mate choice (Beck, Farine, and Kempenaers 2020). Empirical studies generally find that extra-pair partners are more likely to be close neighbours (Westneat and Sherman 1997;Schlicht, Valcu, and Kempenaers 2015;Mingju et al 2017;Beck, Farine, and Kempenaers 2020;Beck, Valcu, and Kempenaers 2020), adding weight to the role of opportunism in extra-pair copulation (as empirically demonstrated by Fossøy, Johnsen, and Lifjeld 2006;and theoretically by Brommer et al 2007;.…”

The costs of extra-pair mating

“…The travel distances required to find potential extra-pair partners can be extensive [57,58] but the energetic expenditure is expected to be low [41]. Indeed, extra-pair partners are often neighbours [24,[59][60][61]. Experimental evidence suggests that search cost may affect the distribution, but not the level, of EPP.…”

Divorce is linked with extra‐pair paternity in a monogamous passerine

“…Accordingly, the number (Oh and Badyaev 2010, Dunning et al 2023a) and quality (Firth and Sheldon 2016, Beck et al 2021) of social associations were shown to be linked to reproductive success, including extra‐pair mate choice (Beck et al 2020a). Extra‐pair partners are more likely to be close neighbours, and extra‐pair paternity increases as a function of population density (Westneat and Sherman 1997, Schlicht et al 2015, Mingju et al 2017, Mennerat et al 2018, Beck et al 2020a, b2020b), adding weight to the role of opportunity in extra‐pair copulation (as empirically demonstrated by Fossøy et al 2006, and theoretically by Brommer et al 2007, 2010).…”