Effects of heterozygosity and MHC diversity on patterns of extra-pair paternity in the socially monogamous scarlet rosefinch

0448645 - BÚ 2016 RIV DE eng J - Journal Article
Winternitz, Jamie Caroline - Promerová, M. - Poláková, R. - Vinkler, M. - Schnitzer, J. - Munclinger, P. - Babik, W. - Radwan, J. - Bryja, J. - Albrecht, T.
Effects of heterozygosity and MHC diversity on patterns of extra-pair paternity in the socially monogamous scarlet rosefinch.
Behavioral Ecology and Sociobiology. Roč. 69, č. 3 (2015), s. 459-469. ISSN 0340-5443. E-ISSN 1432-0762
R&D Projects: GA MŠMT(CZ) EE2.3.30.0048
Institutional support: RVO:67985939
Keywords : extra-pair copulation * major histocompatibility complex * Erythrina erythrina
Subject RIV: EH - Ecology, Behaviour
Impact factor: 2.382, year: 2015

Extra-pair copulation without apparent direct benefits is an evolutionary puzzle that requires indirect fitness benefits to females to explain its ubiquity in socially monogamous mating systems. Using wild scarlet rosefinches (Carpodacus erythrinus), we tested if genetic benefits in the form of global (microsatellite) heterozygote advantage, adaptive genes (major histocompatibility complex), or complementary genes (using both markes) were responsible for female extra-pair mate choice, while considering that the benefits of mate choice may be conditional on female genotype. We found no evidence for assortative or relatedness-based mating (complementary genes), but higher MHC diversity, microsatellite heterozygosity, and condition were significantly related to male extra-pair paternity (EPP) success. In contrast, female probability of having extra-pair offspring decreased with increasing heterozygosity. Interestingly, extra-pair and within-pair males had higher heterozygosity than their female mates and extra-pair males had higher MHC supertype diversity. The only genetic difference between extra-pair and within-pair offspring was lower variace in MHC allelic diversity within extra-pair offspring, providing limited support for indirect genetic fitness benefits for the markers tested. Offspring had both higher neutral heterozygosity and number of MHC supertypes than adults, as well as significant identity disequilibrum, potentially suggesting that mates are chosen to increase offspring diversity in the period of the present study. Overall, our results point to an EPP heterozygote advantage for males, especially when involving less heterozygous females, and suggest that heterozygosity effects on reproduction may differ between the sexes.
Permanent Link: http://hdl.handle.net/11104/0250289