Occurrence of extra-pair paternity is connected to social male's MHC-variability in the scarlet rosefinch Carpodacus erythrinus
Abstrakt
The MHC genes represent an essential component of the vertebrate immune system. Their role in mate choice has been subject of particular scientific interest in the last decades.
However, results of studies dealing with this topic in different species are equivocal and mechanisms conducting MHC-based mate choice are still puzzling. We studied the impact of MHC class I variability on within- and extra-pair fertilisation success in a socially monogamous passerine bird with considerable rates of extra-pair paternity, the Scarlet rosefinch (Carpodacus erythrinus).
We found support for the 'good-genes-as-heterozygosity model', as social males of high MHC-heterozygosity were cheated by females less frequently than less MHC-heterozygous males. However, cuckolding males were not more MHC-heterozygous than the cheated social males, nor were extra-pair young more MHC-heterozygous than within-pair young.
We did not find any evidence for mating preferences according to the complementarity model.