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Theory predicts that temporal variability plays an important role in the evolution of life histories, but empirical studies evaluating this prediction are rare. In constant environments, fitness can be measured by the population growth rate λ, and the sensitivity of λ to changes in fitness components estimates selection on these traits. In variable environments, fitness is measured by the stochastic growth rate λ_s, and stochastic sensitivities estimate selection pressure. Here we examine age‐specific schedules for reproduction and survival in a barn owl population (Tyto alba). We estimated how temporal variability affected fitness and selection, accounting for sampling variance. Despite large sample sizes of old individuals, we found no strong evidence for senescence. The most variable fitness components were associated with reproduction. Survival was less variable. Stochastic simulations showed that the observed …