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Parental stress often has long-term consequences for offspring. However, the mechanisms underlying these effects and how they are shaped by conditions offspring subsequently experience are poorly understood. Telomeres, which often shorten in response to stress and predict longevity, may contribute to, and/or reflect these cross-generational effects. Traditionally, parental stress is expected to have negative effects on offspring telomeres, but experimental studies in captive animals suggest that these effects may depend on the subsequent conditions that offspring experience. Yet, the degree to which parental stress influences and interacts with stress experienced by offspring to affect offspring telomeres and survival in free-living organisms is unknown. To assess this, we experimentally manipulated the stress exposure of free-living parent and offspring house sparrows ( Passer domesticus ). We found a weak, initial, negative effect of parental stress on offspring telomeres, but this effect was no longer evident at the end of post-natal development. Instead, the effects of parental stress depended on the natural sources of stress that offspring experienced during post-natal development whereby some outcomes were improved under more stressful rearing conditions. Thus, the effects of parental stress on offspring telomeres and survival are context-dependent and may involve compensatory mechanisms of potential benefit under some circumstances.
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Cross‐Generational Effects of Parental Age on Offspring Longevity: Are Telomeres an Important Underlying Mechanism?
Abstract Parental age at offspring conception often influences offspring longevity, but the mechanisms underlying this link are poorly understood. One mechanism that may be important is telomeres, highly conserved, repetitive sections of non‐coding DNA that form protective caps at chromosome ends and are often positively associated with longevity. Here, the potential pathways by which the age of the parents at the time of conception may impact offspring telomeres are described first, including direct effects on parental gamete telomeres and indirect effects on offspring telomere loss during pre‐ or post‐natal development. Then a surge of recent studies demonstrating the effects of parental age on offspring telomeres in diverse taxa are reviewed. In doing so, important areas for future research and experimental approaches that will enhance the understanding of how and when these effects likely occur are highlighted. It is concluded by considering the potential evolutionary consequences of parental age on offspring telomeres.
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- Award ID(s):
- 1656194
- PAR ID:
- 10455324
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- BioEssays
- Volume:
- 42
- Issue:
- 9
- ISSN:
- 0265-9247
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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