The role of telomeres in the mechanisms and evolution of life-history trade-offs and ageing
Philosophical Transactions B: Biological Sciences
© 2018 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
Evolutionary biology and biomedicine have seen a surge of recent interest in the possibility that telomeres play a role in life-history trade-offs and ageing. Here I evaluate alternative hypotheses for the role of telomeres in the mechanisms and evolution of life-history trade-offs and ageing, and highlight outstanding challenges. First, while recent findings underscore the possibility of a proximate causal role for telomeres in current-future trade-offs and ageing, it is currently unclear (i) whether telomeres ever play a causal role in either, and (ii) whether any causal role for telomeres arises via shortening or length-independent mechanisms. Second, I consider why, if telomeres do play a proximate causal role, selection has not decoupled such a telomere-mediated trade-off between current and future performance. Evidence suggests that evolutionary constraints have not rendered such decoupling impossible. Instead, a causal role for telomeres would more plausibly reflect an adaptive strategy, born of telomere maintenance costs and/or a function for telomere attrition (e.g. in countering cancer), the relative importance of which is currently unclear. Finally, I consider the potential for telomere biology to clarify the constraints at play in life-history evolution, and to explain the form of the current-future trade-offs and ageing trajectories that we observe today.
I extend particular thanks to Pat Monaghan, Dan Nussey and Mark Haussmann and the Leverhulme Trust for organising and funding the meetings between evolutionary and biomedical researchers that have stimulated this special issue; long may this network flourish.
This is the author accepted manuscript. The final version is available from The Royal Society via the DOI in this record.
Volume 373, issue 1741, article 20160452