Data from: Evidence of reduced individual heterogeneity in adult survival of long-lived species

The canalization hypothesis postulates that traits with greater impact on fitness should be under stronger stabilizing selection than traits with less impact on fitness. The ranking of a given species on the slow-fast continuum – the covariation among life-history traits describing species-specific life cycles along a gradient from a long life, slow maturity, and low annual reproductive output, to a short life, fast maturity, and high annual reproductive output – strongly correlates with the relative fitness impact of variation in adult survival. This should lead long-lived species to display less individual heterogeneity in adult survival than short-lived species. We tested this life history prediction by analysing long-term time series of individual-based data in nine species of birds and mammals using capture-recapture models. We found that individual heterogeneity in adult survival was more marked in species with short generation time (< 3 years) than in species with long generation time (>4 years). Our findings provide the first empirical support of the canalization hypothesis at the individual level from the wild.