Correctly estimating how environmental stochasticity influences fitness and population growth.

Journal Article (Journal Article)

Increased temporal variance in life-history traits is generally predicted to decrease individual fitness and population growth. We show that a widely used result of stochastic sensitivity analysis that bolsters this generality is flawed because it ignores the effects of correlations between vital rates. Considering the effects of these correlations (although ignoring autocorrelations), we show that the apparently simple relationship between vital rate variance and fitness can be considerably more complex than previously thought. In particular, the previously estimated negative sensitivities of fitness or population growth to variance in a vital rate can be either enhanced by positive correlations between rates or reversed by negative correlations, even to the point that variability in a rate can increase fitness or population growth. We apply this new sensitivity calculation to data from the desert tortoise and discuss its interpretation in light of the factors generating vital rate correlations.

Full Text

Duke Authors

Cited Authors

  • Doak, DF; Morris, WF; Pfister, C; Kendall, BE; Bruna, EM

Published Date

  • July 2005

Published In

Volume / Issue

  • 166 / 1

Start / End Page

  • E14 - E21

PubMed ID

  • 15937784

Electronic International Standard Serial Number (EISSN)

  • 1537-5323

International Standard Serial Number (ISSN)

  • 0003-0147

Digital Object Identifier (DOI)

  • 10.1086/430642


  • eng