Extra-pair paternity explains cooperation in a bird species

• DOI: 10.1073/pnas.2112004119
• Publication Date: 2022-01-18T22:55:23Z
• Authors: Indrikis A. Krams; Adèle Mennerat; Tatjana Krama; Ronalds Krams; Priit Jõers; Didzis Elferts; Severi Luoto; Markus J. Rantala; Sigrunn Eliassen
• Keywords: [SDV] Life Sciences [q-bio]; Male; 570; Sexual Behavior, Animal; Reproduction; Copulation; 590; ta1181; Animals; Female; Passeriformes; Biological Sciences

Significance In many monogamous species, a substantial proportion of offspring is sired by other males than the one providing care at the nest. Although females often solicit extra-pair mating, the benefits of extra-pair copulations to females are not fully understood. In this study on pied flycatchers, we tested whether extra-pair paternity in neighboring nests may have affected the likelihood that males helped defend extra-pair offspring against predators. We found that extra-pair sires were more often engaged and invested more heavily in cooperative predator defense than males without extra-pair offspring. For female flycatchers, extra-pair mating may thus be an adaptive strategy for enhancing offspring survival and breeding success.