Abstract
Age-specific mortality rates were studied at two adult density levels in four inbred lines of Drosophila melanogaster. In experimental populations, adult densities were maintained at constant levels throughout the experiment by replacing dead flies with live, marked mutants. In control populations, densities declined naturally as the cohorts aged. For all experimental populations the best mortality model is the two-stage Gompertz model, with slower mortality acceleration at older ages. Flies in the experimental populations generally lived longer than flies in control populations, regardless of sex, genotype, or initial density level. The data demonstrate that deceleration of age-specific mortality rates at older ages is not caused by declining cohort densities. Mortality deceleration is a real phenomenon that raises serious questions about the evolution of senescence.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Brooks, A., G.J. Lithgow & T.E. Johnson, 1994. Genetic control of life span: Age-specific mortality rate of heterogeneous population of Caenorhabditis elegans. Science 263: 668–671.
Carey, J.R., P. Liedo, D. Orozco & J.W. Vaupel, 1992. Slowing of mortality rates at older ages in largely medfly cohort. Science 258: 457–461.
Clark, A.G. & R.N. Guadalupe, 1995. Probing the evolution of senescence in Drosophila melanogaster with P-element tagging. Genetica, in press.
Curtsinger, J.W., 1995a. Density and age-specific mortality. Genetica 96: 179–82.
Curtsinger, J.W., 1995b. Density, mortality, and the narrow view. Genetica 96: 187–89.
Curtsinger, J.W., 1995c. Review of Evolution in Age-Structure Populations, by B. Charlesworth. Exp. Geron. 30: in press.
Curtsinger, J.W., H.H. Fukui, D.R. Townsend & J.W. Vaupel, 1992. Demography of genotypes: Failure of the limited life-span paradigm in Drosophila melanogaster. Science 258: 461–463.
Curtsinger, J.W., H.H. Fukui, A.A. Khazaeli, A. Kirscher, S.D. Pletcher, D.E.L. Promislow & M. Tatar, 1995. Genetic variation and aging. Ann. Rev. Genetics 29: 553–575.
Fukui, H.H., L. Ackert & J.W. Curtsinger, 1996. Deceleration of age-specific mortality rates in chromosomal homozygotes and heterozygotes of Drosophila melanogaster. Exp. Gerontol., in press.
Fukui, H.H. & A.W. Kirscher, 1993. Thanatometer II. A chamber designed for large mixed-sex populations of Drosophila melanogaster. Drosophila Information Service 72: 72–73.
Fukui, H.H., L. Xiu & J.W. Curtsinger, 1993. Slowing of age-specific mortality rates in Drosophila melanogaster. Exp. Gerontol. 28: 585–599.
Graves, J.L. & L.D. Mueller, 1993. Population density effects on longevity. Genetica 99: 99–109.
Khazaeli, A.A., L. Xiu & J.W. Curtsinger, 1994. Stress experiments as a means of examining age-specific mortality in Drosophila melanogaster. Exp. Gerontol. 30: 177–184.
Khazaeli, A.A., L. Xiu & J.W. Curtsinger, 1995. Effect of adult cohort density on age-specific mortality in Drosphila melanogaster. J. Gerontol. 50A: 262–269.
Kowald, A. & J.B.L. Kirkwood, 1993. Explaining fruit fly longevity. Science 260: 1664–65.
Nusbaum, T.J., J.L. Graves, L.D. Mueller & M.R. Rose, 1993. Fruit fly aging and mortality. Science 260: 1567.
Remlau-Hansen, H., 1983. Smoothing counting process intensities by means of kernel functions. Ann. Statistics II: 453–466.
Robine, J.M. & K. Ritchie, 1993. Explaining fruit fly longevity. Science 260: 1664.
Vaupel, J.W. & J.R. Carey, 1993. Compositional interpretations of Medfly mortality. Science 260: 1666–67.
Vaupel, J.W., J.R. Carey & P. Liedo, 1996. Medfly mertality decline not due to declining density. Experimental Gerontology, in press.
Vaupel, J.W., T.E. Johnson & G.J. Lithgow, 1994. Rates of mortality in populations of Caenorhobditis elegans, Science 266: 826.
Weber, K.E. & L.T. Diggins, 1990. Increased selection response in populations. II Selection for Ethanol vapor resistance in Drosophila melanogaster. Genetics 125: 588–597.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Khazaeli, A.A., Xiu, L. & Curtsinger, J.W. Effect of density on age-specific mortality in Drosophila: a density supplementation experiment. Genetica 98, 21–31 (1996). https://doi.org/10.1007/BF00120215
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00120215