title: Variation in phenotypic plasticity and selection patterns in blue tit breeding time: between- and within-population comparisons.
abstract: 1. Phenotypic plasticity, the response of individual phenotypes to their environment, can allow organisms to cope with spatio-temporal variation in environmental conditions. Recent studies have shown that variation exists among individuals in their capacity to adjust their traits to environmental changes and that this individual plasticity can be under strong selection. Yet, little is known on the extent and ultimate causes of variation between populations and individuals in plasticity patterns. 2. In passerines, timing of breeding is a key life-history trait strongly related to fitness and is known to vary with the environment, but few studies have investigated the within-species variation in individual plasticity. 3. Here, we studied between- and within-population variation in breeding time, phenotypic plasticity and selection patterns for this trait in four Mediterranean populations of blue tits (Cyanistes caeruleus) breeding in habitats varying in structure and quality. 4. Although there was no significant warming over the course of the study, we found evidence for earlier onset of breeding in warmer years in all populations, with reduced plasticity in the less predictable environment. In two of four populations, there was significant inter-individual variation in plasticity for laying date. Interestingly, selection for earlier laying date was significant only in populations where there was no inter-individual differences in plasticity. 5. Our results show that generalization of plasticity patterns among populations of the same species might be challenging even at a small spatial scale and that the amount of within-individual variation in phenotypic plasticity may be linked to selective pressures acting on these phenotypic traits.
authors.affiliation: Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada. melody.porlier@usherbrooke.ca
authors.forename: Melody
authors.initials: M
authors.lastname: Porlier
authors.forename: Anne
authors.initials: A
authors.lastname: Charmantier
authors.forename: Patrice
authors.initials: P
authors.lastname: Bourgault
authors.forename: Philippe
authors.initials: P
authors.lastname: Perret
authors.forename: Jacques
authors.initials: J
authors.lastname: Blondel
authors.forename: Dany
authors.initials: D
authors.lastname: Garant
mesh_terms: D000818:Animals; D052284:Clutch Size; D003710:Demography; D005260:Female; D008297:Male; D008954:Models, Biological; D010058:Oviposition; D046109:Passeriformes / Q000235:genetics* / Q000502:physiology*; D012641:Selection, Genetic; D013997:Time Factors; D014197:Trees / Q000145:classification