DISSERTATION RESEARCH: The Evolution of Late-Life Fecundity

University Of California-Irvine, Irvine CA

Investigators

Abstract

The objective of this proposal is to test general theories of late life - both evolutionary and non-evolutionary - using fecundity. Thus far, fecundity has been shown to plateau late in life and evolve according to evolutionary theory. Alternative non-evolutionary hypotheses have not been able to satisfactorily explain these results, as late-life fecundity plateaus do not arise from diminished male sexual function, nutritional effects, or mortality-rate plateaus. The proposed experiments will specifically test the heterogeneity and antagonistic pleiotropy theories of late life, using Drosophila melanogaster. Heterogeneity in fecundity will be tested by measuring lifetime individual fecundity within a large cohort and comparing fecundity patterns of females that survive to the fecundity plateau with those that do not. Antagonistic pleiotropy between late-life fecundity and early fitness will be tested using 25 generations of selection for earlier reproduction, followed by a comparison of late-life fecundity between the early-reproducing cohorts and the original later-reproducing cohorts.