Campus Units
Ecology, Evolution and Organismal Biology
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
2016
Journal or Book Title
Proceedings of the National Academy of Sciences
Volume
113
Issue
23
First Page
6502
Last Page
6507
DOI
10.1073/pnas.1600035113
Abstract
Lifespan and aging rates vary considerably across taxa; thus, understanding the factors that lead to this variation is a primary goal in biology and has ramifications for understanding constraints and flexibility in human aging. Theory predicts that senescence—declining reproduction and increasing mortality with advancing age—evolves when selection against harmful mutations is weaker at old ages relative to young ages or when selection favors pleiotropic alleles with beneficial effects early in life despite late-life costs. However, in many long-lived ectotherms, selection is expected to remain strong at old ages because reproductive output typically increases with age, which may lead to the evolution of slow or even negligible senescence. We show that, contrary to current thinking, both reproduction and survival decline with adult age in the painted turtle, Chrysemys picta, based on data spanning >20 y from a wild population. Older females, despite relatively high reproductive output, produced eggs with reduced hatching success. Additionally, age-specific mark–recapture analyses revealed increasing mortality with advancing adult age. These findings of reproductive and mortality senescence challenge the contention that chelonians do not age and more generally provide evidence of reduced fitness at old ages in nonmammalian species that exhibit long chronological lifespans.
Copyright Owner
Warner et al.
Copyright Date
2016
Language
en
File Format
application/pdf
Recommended Citation
Warner, Daniel A.; Miller, David A. W.; Bronikowski, Anne M.; and Janzen, Fredric J., "Decades of field data reveal that turtles senesce in the wild" (2016). Ecology, Evolution and Organismal Biology Publications. 175.
https://lib.dr.iastate.edu/eeob_ag_pubs/175
Included in
Evolution Commons, Population Biology Commons, Terrestrial and Aquatic Ecology Commons, Zoology Commons
Comments
This is a manuscript of an article from Proceedings of the National Academy of Sciences 113 (2016): 6502, doi: 10.1073/pnas.1600035113. Posted with permission.