title: The strength of the association between heterozygosity and probability of interannual local recruitment increases with environmental harshness in blue tits.
abstract: The extent of inbreeding depression and the magnitude of heterozygosity-fitness correlations (HFC) have been suggested to depend on the environmental context in which they are assayed, but little evidence is available for wild populations. We combine extensive molecular and capture-mark-recapture data from a blue tit (Cyanistes caeruleus) population to (1) analyze the relationship between heterozygosity and probability of interannual adult local recruitment and (2) test whether environmental stress imposed by physiologically suboptimal temperatures and rainfall influence the magnitude of HFC. To address these questions, we used two different arrays of microsatellite markers: 14 loci classified as neutral and 12 loci classified as putatively functional. We found significant relationships between heterozygosity and probability of interannual local recruitment that were most likely explained by variation in genomewide heterozygosity. The strength of the association between heterozygosity and probability of interannual local recruitment was positively associated with annual accumulated precipitation. Annual mean heterozygosity increased over time, which may have resulted from an overall positive selection on heterozygosity over the course of the study period. Finally, neutral and putatively functional loci showed similar trends, but the former had stronger effect sizes and seemed to better reflect genomewide heterozygosity. Overall, our results show that HFC can be context dependent, emphasizing the need to consider the role of environmental heterogeneity as a key factor when exploring the consequences of individual genetic diversity on fitness in natural populations.
authors.affiliation: Grupo de Investigación de la Biodiversidad Genética y Cultural Instituto de Investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM) Ciudad Real Spain; Departamento de Ciencias Ambientales Facultad de Ciencias Ambientales y Bioquímica Universidad de Castilla-La Mancha Toledo Spain.
authors.forename: Esperanza S
authors.initials: ES
authors.lastname: Ferrer
authors.affiliation: Grupo de Investigación de la Biodiversidad Genética y Cultural Instituto de Investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM) Ciudad Real Spain; Departamento de Ciencias Ambientales Facultad de Ciencias Ambientales y Bioquímica Universidad de Castilla-La Mancha Toledo Spain; Institute of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland; Department of Integrative Ecology Estación Biológica de Doñana (EBD-CSIC) Seville Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: García-Navas
authors.affiliation: Departamento de Ecología Evolutiva Museo Nacional de Ciencias Naturales (CSIC) Madrid Spain.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Sanz
authors.affiliation: Department of Integrative Ecology Estación Biológica de Doñana (EBD-CSIC) Seville Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Ortego
keywords: Cyanistes caeruleus; HFC; functional and neutral markers; genotype‐by‐environment interaction; heterozygosity; selection differential