Abstract
Age specific mortality trajectories were estimated in mixed-sex cohorts of D. melanogaster. We studied 22,000 flies that were either second- chromosome homozygotes or heterozygotes with a randomized genetic background. Broad-sense heritabilities for longevity were estimated to be 6% for males and 9% for females. Heterozygotes lived longer than homozygotes on average, but there were exceptions to the usual heterotic pattern; in several crosses parental homozygotes had average life spans as long as that of their F1 heterozygotes. Estimated age-specific mortality rates were found to decelerate at advanced ages in both homozygotes and heterozygotes. The mortality models that best fit the data are the logistic model and the two- stage Gompertz model, both of which produce mortality trajectories that level off at advanced ages. Old-age mortality deceleration is not peculiar to inbred Drosophila.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 517-531 |
| Number of pages | 15 |
| Journal | Experimental Gerontology |
| Volume | 31 |
| Issue number | 4 |
| DOIs | |
| State | Published - 1996 |
Bibliographical note
Funding Information:Acknowledgments--We thank D. Promislow and M. Tatar for comments on the manuscript, and C. Misiak and A. Resler for technical assistance. Research is supported by grants from the National Institutes of Health (PO1 AG08761) and the Graduate School, University of Minnesota.
Keywords
- Gompertz model
- age-specific mortality
- logistic model
- mortality deceleration
- two-stage Gompertz model