Citation

Baudisch A. Gerontology 2012; 58(6): 481-489.

Affiliation

Max Planck Research Group 'Modelling the Evolution of Ageing', Max Planck Institute for Demographic Research, Rostock, Germany.

Copyright

(Copyright © 2012, Karger Publishers)

DOI

10.1159/000341861

PMID

22948534

Abstract

Organisms of different species age differently. Current theory explains why life should get worse, i.e. why patterns of increasing risk of death should evolve. However, for some species the risk of death remains constant or even falls with advancing age. Evolutionary theory to explain the observed diversity of shapes of ageing is lacking. Theoretical models can provide insights into this diversity. Comparing assumptions of models that find increasing mortality patterns with models that find a variety of patterns, including constant and falling mortality over age, I identify conditions that licence constant or negative shapes of ageing. The results suggest that patterns of improvement and maintenance over age emerge when models potentially allow organisms to (1) escape the 'damage ratchet', (2) achieve maintenance and repair in parallel, (3) face increasing future reproductive potential and (4) incorporate flexible trade-offs. With these insights, theoretical models contribute to hypotheses about which species may follow life history strategies of negligible or negative ageing.

Language: en