Parental genetic similarity and offspring performance in blue tits in relation to brood size manipulation

• Published in: Ecology and Evolution
• Main Authors: Aneta Arct, Szymon M. Drobniak, Samantha Mellinger, Lars Gustafsson, Mariusz Cichoń
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2019
• Subjects: birds; brood size manipulation; immune response; inbreeding; mate choice; microsatellite; Ecology; QH540-549.5; Avian Studies
• Online Access: https://doi.org/10.1002/ece3.5367; https://doaj.org/article/a87c59a0e98f4f578135cf4bee3eab15

Abstract In birds, as in many other taxa, higher genetic similarity of mates has long been known to reduce offspring fitness. To date, the majority of avian studies have focused on examination whether the genetic similarity of social mates predicts hatching success. Yet, increased genetic similarity of mates may also reduce offspring fitness during later life stages, including the nestling period and beyond. Here, we investigated whether parental genetic similarity influences offspring performance using data from free‐living blue tits (Cyanistes caeruleus) collected across three breeding seasons. Additionally, we tested whether brood size manipulation affects the magnitude and direction of the relationship between genetic similarity of mates and offspring performance. Sixteen microsatellite markers were used to measure genetic similarity between biological parents. We found that the genetic similarity of parents negatively affects offspring immune response and this effect was independent of the experimental brood size manipulation.