Centre for Biodiversity Dynamics, Department of Biology, Faculty of Natural Sciences and Technology, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, NO-7491, Trondheim, Norway.
Institute of Biodiversity, Animal Health and Comparative Medicine, Graham Kerr Building, University of Glasgow, Glasgow, G12 8QQ, UK.
Nat Commun. 2019 Feb 1;10(1):538. doi: 10.1038/s41467-019-08502-9.
Reversible phenotypic plasticity, the ability to change one's phenotype repeatedly throughout life, can be selected for in environments that do not stay constant throughout an individual's lifetime. It might also mitigate senescence, as the mismatch between the environment and a non-plastic individual's traits is likely to increase as time passes. To understand why reversible plasticity may covary with lifespan, studies tend to assume unidirectional causality: plasticity evolves under suitable rates of environmental variation with respect to life history. Here we show that if lifespan also evolves in response to plasticity, then long life is not merely a context that sets the stage for lifelong plasticity. Instead, the causality is bidirectional because plasticity itself can select for longevity. Highly autocorrelated environmental fluctuations predict low investment in reversible plasticity and a phenotype that is poorly matched to the environment at older ages. Such environments select for high reproductive effort and short lifespans.
可逆表型可塑性是指个体在一生中能够多次改变表型的能力，如果环境不会在个体的一生中保持不变，那么这种能力就可以被选择。它还可以减轻衰老，因为随着时间的推移，环境与非可塑性个体的特征之间的不匹配很可能会增加。为了理解为什么可逆可塑性可能与寿命相关，研究倾向于假设单向因果关系：可塑性是在适合的环境变化率下进化的，而这些变化率与生活史有关。在这里，我们表明，如果寿命也对可塑性做出反应，那么长寿不仅仅是一个为终生可塑性奠定基础的背景。相反，因果关系是双向的，因为可塑性本身可以选择长寿。高度自相关的环境波动预示着对可逆可塑性的低投资和在老年时与环境匹配不良的表型。这种环境选择了高生殖力和短寿命。
