Age-specific fitness components and their temporal variation in the barn owl.

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Version: author
Serval ID
serval:BIB_692C3D5630EF
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Age-specific fitness components and their temporal variation in the barn owl.
Journal
American Naturalist
Author(s)
Altwegg R., Schaub M., Roulin A.
ISSN
1537-5323[electronic], 0003-0147[linking]
Publication state
Published
Issued date
2007
Peer-reviewed
Oui
Volume
169
Number
1
Pages
47-61
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
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 lambda, and the sensitivity of lambda to changes in fitness components estimates selection on these traits. In variable environments, fitness is measured by the stochastic growth rate lambda(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 variation decreased fitness by about 30%, but the sensitivities of lambda and lambda(S) to changes in all fitness components were almost equal, suggesting that temporal variation had negligible effects on selection. We obtained these results despite high observed variability in the fitness components and relatively short generation time of the study organism, a situation in which temporal variability should be particularly important for natural selection and early senescence is expected.
Keywords
Age Factors, Animals, Clutch Size, Female, Male, Models, Biological, Population Dynamics, Reproduction/physiology, Selection, Genetic, Strigiformes/physiology, Survival Rate
Pubmed
Web of science
Create date
24/01/2008 18:42
Last modification date
20/08/2019 15:24
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