Age‐Specific Fitness Components and Their Temporal Variation in the Barn Owl

  title={Age‐Specific Fitness Components and Their Temporal Variation in the Barn Owl},
  author={Res Altwegg and Michael Schaub and Alexandre Roulin},
  journal={The American Naturalist},
  pages={47 - 61}
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 λs, and stochastic sensitivities estimate selection pressure. Here we examine age… 
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