Environmental Effects on the Expression of Life Span and Aging: An Extreme Contrast between Wild and Captive Cohorts of Telostylinus angusticollis (Diptera: Neriidae)

Authors

Noriyoshi Kawasaki, Evolution and Ecology Research Centre and School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, New South Wales, Australia
Chad Brassil, University of Nebraska - LincolnFollow
Robert Brooks, Evolution and Ecology Research Centre and School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, New South Wales, Australia
Russell Bonduriansky, Evolution and Ecology Research Centre and School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, New South Wales, Australia

Document Type

Article

Date of this Version

9-2008

Comments

Published in Am. Nat. 2008. Vol. 172, pp. 346–357. Copyright © 2008 by The University of Chicago. Used by permission.

Abstract

Most research on life span and aging has been based on captive populations of short-lived animals; however, we know very little about the expression of these traits in wild populations of such organisms. Because life span and aging are major components of fitness, the extent to which the results of many evolutionary studies in the laboratory can be generalized to natural settings depends on the degree to which the expression of life span and aging differ in natural environments versus laboratory environments and whether such environmental effects interact with phenotypic variation. We investigated life span and aging in Telostylinus angusticollis in the wild while simultaneously estimating these parameters under a range of conditions in a laboratory stock that was recently established from the same wild population. We found that males live less than one-fifth as long and age at least twice as rapidly in the wild as do their captive counterparts. In contrast, we found no evidence of aging in wild females. These striking sex-specific differences between captive and wild flies support the emerging view that environment exerts a profound influence on the expression of life span and aging. These findings have important implications for evolutionary gerontology and, more generally, for the interpretation of fitness estimates in captive populations.