Data from: Mhc-linked survival and lifetime reproductive success in a wild population of great tits

Major histocompatibility complex (Mhc) genes are frequently used as a
model for adaptive genetic diversity. Although associations between Mhc
and disease resistance are frequently documented, little is known about
the fitness consequences of Mhc variation in wild populations. Further,
most work to date has involved testing associations between Mhc genotypes
and fitness components. However, the functional diversity of the Mhc, and
hence the mechanism by which selection on Mhc acts, depends on how
genotypes map to the functional properties of Mhc molecules. Here, we test
three hypotheses that relate Mhc diversity to fitness: (1) the maximal
diversity hypothesis; (2) the optimal diversity hypothesis, and (3) effect
of specific Mhc types. We combine mark-recapture methods with analysis of
long-term breeding data to investigate the effects of Mhc class I
functional diversity (Mhc supertypes) on individual fitness in a wild
great tit (Parus major) population. We found that the presence of three
different Mhc supertypes was associated with three different components of
individual fitness: survival, annual recruitment and lifetime reproductive
success (LRS). Great tits possessing Mhc supertype 3 experienced higher
survival rates than those that did not, whereas individuals with Mhc
supertype 6 experienced higher LRS and were more likely to recruit
offspring each year. Conversely, great tits that possessed Mhc supertype 5
had reduced LRS. We found no evidence for a selective advantage of Mhc
diversity, either in terms of maximal or optimal supertype diversity. Our
results support the suggestion that specific Mhc types are an important
determinant of individual fitness.