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bioRxiv · 10.1101/2023.08.16.553597

A future food boom rescues the negative effects of cumulative early-life adversity on lifespan in a small mammal

Petrullo, L.·Delaney, D.·Boutin, S.·Lane, J. E.·McAdam, A. G.·Dantzer, B.
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Abstract

Adverse early-life conditions, even when transient, can have long-lasting effects on individual phenotypes and reduce lifespan across species. If these effects can be mitigated. by a high quality later-life environment, then differences in future resource access may explain variation in vulnerability and resilience to early-life adversity. Using 32 years of data on 1,000+ wild North American red squirrels, we tested the hypothesis that the negative effects of early-life adversity on lifespan can be buffered by later-life food abundance. We found that although cumulative early-life adversity was negatively associated with adult lifespan, this relationship was modified by future food abundance. Squirrels that experienced a naturally-occurring future food boom in the second year of life did not suffer reduced longevity despite early-life adversity. Experimental supplementation with additional food did not replicate this effect, though it did increase adult lifespan overall. Our results suggest a non-deterministic role for early-life conditions on later-life phenotypes, and highlight the importance of contextualizing the influence of harsh early-life conditions over an animals entire life course.

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Petrullo, L., Delaney, D., Boutin, S., Lane, J. E., McAdam, A. G., Dantzer, B.. 2023-08-18. A future food boom rescues the negative effects of cumulative early-life adversity on lifespan in a small mammal. https://doi.org/10.1101/2023.08.16.553597

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