title: Major histocompatibility complex class II compatibility, but not class I, predicts mate choice in a bird with highly developed olfaction.
abstract: Mate choice for major histocompatibility complex (MHC) compatibility has been found in several taxa, although rarely in birds. MHC is a crucial component in adaptive immunity and by choosing an MHC-dissimilar partner, heterozygosity and potentially broad pathogen resistance is maximized in the offspring. The MHC genotype influences odour cues and preferences in mammals and fish and hence olfactory-based mate choice can occur. We tested whether blue petrels, Halobaena caerulea, choose partners based on MHC compatibility. This bird is long-lived, monogamous and can discriminate between individual odours using olfaction, which makes it exceptionally well suited for this analysis. We screened MHC class I and II B alleles in blue petrels using 454-pyrosequencing and quantified the phylogenetic, functional and allele-sharing similarity between individuals. Partners were functionally more dissimilar at the MHC class II B loci than expected from random mating (p = 0.033), whereas there was no such difference at the MHC class I loci. Phylogenetic and non-sequence-based MHC allele-sharing measures detected no MHC dissimilarity between partners for either MHC class I or II B. Our study provides evidence of mate choice for MHC compatibility in a bird with a high dependency on odour cues, suggesting that MHC odour-mediated mate choice occurs in birds.
authors.affiliation: Behavioral Ecology Group, CEFE-CNRS, 1919 Route de Mende, Montpellier Cedex 5, France. maria.strandh@biol.lu.se
authors.forename: Maria
authors.initials: M
authors.lastname: Strandh
authors.forename: Helena
authors.initials: H
authors.lastname: Westerdahl
authors.forename: Mikael
authors.initials: M
authors.lastname: Pontarp
authors.forename: Björn
authors.initials: B
authors.lastname: Canbäck
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Dubois
authors.forename: Christian
authors.initials: C
authors.lastname: Miquel
authors.forename: Pierre
authors.initials: P
authors.lastname: Taberlet
authors.forename: Francesco
authors.initials: F
authors.lastname: Bonadonna
mesh_terms: D000818:Animals; D000864:Antarctic Regions; D001717:Birds / Q000235:genetics / Q000502:physiology*; D005091:Exons; D005260:Female; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D005838:Genotype; D007195:Indian Ocean Islands; D008297:Male; D052586:Mating Preference, Animal; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012903:Smell