Abstract
The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution.
| Original language | English |
|---|---|
| Article number | 24672 |
| Journal | Scientific Reports |
| Volume | 6 |
| DOIs | |
| State | Published - Apr 18 2016 |
| Externally published | Yes |
Funding
This study has been approved by the University of Utah's Resource for Genetic and Epidemiologic Research and its Institutional Review Board. We thank the Pedigree and Population Resource of the Huntsman Cancer Institute, University of Utah (funded in part by the Huntsman Cancer Foundation) for its role in the ongoing collection, maintenance and support of the Utah Population Database (UPDB). We are grateful to the Wenner-Gren-Foundations (E.B.), the European Research Council (A.A.M.), the Academy of Finland (VL), the Swedish Research Council (A.A.M.) and the National Institutes of Health (Grant AG022095 (K.S) for funding.