Sex-dependent integration of ornamentation, personality, morphology and life history

Phenotypic integration can be defined as the patterns and strength of the covariance between traits in an organism. The pace of life syndrome (POLS) hypothesis provides a testable case of phenotypic integration as it predicts that traits that mediate the trade-off between current and future reproduction, should have coevolved with the slow-fast life-history continuum, and may thus covary across individuals of a population. Although the POLS hypothesis has received increasing attention over the last decade, there is still a need for investigating whether POLS are sex-specific or if ornamental traits can be included within the POLS framework. We used nine years of data to describe the integration patterns of ornamental coloration, personality, morphology and life history in blue tits (Cyanistes caeruleus) and whether they differed between males and females. With that aim, we fitted multivariate mixed models separating the among- from the within-individual covariances. We found that the ov...