Evolutionary rescue via transgenerational plasticity: Evidence and implications for conservation

Abstract

When a population experiences severe stress from a changing environment, evolution by natural selection can prevent its extinction, a process dubbed “evolutionary rescue.” However, evolution may be unable to track the sort of rapid environmental change being experienced by many modern‐day populations. A potential solution is for organisms to respond to environmental change through phenotypic plasticity, which can buffer populations against change and thereby buy time for evolutionary rescue. In this review, we examine whether this process extends to situations in which the environmentally induced response is passed to offspring. As we describe, theoretical and empirical studies suggest that such “transgenerational plasticity” can increase population persistence. We discuss the implications of this process for conservation biology, outline potential limitations, and describe some applications. Generally, transgenerational plasticity may be effective at buying time for evolutionary rescue to occur.

Separating Paternal and Maternal Contributions to Thermal Transgenerational Plasticity

“…Environmental conditions are changing rapidly in both marine and freshwater environments (Scavia et al, 2002) and TGP may dampen selection resulting from a change in environment (Donelson et al, 2018). As such, TGP may mitigate population decline by alleviating a "phenotype-environment mismatch, " ultimately buying time for evolutionary rescue (DeWitt et al, 1998;Marshall et al, 2010;Harmon and Pfennig, 2021). However, although plasticity represents an organismal capacity for extremely rapid phenotypic changes over a single generation, it is unclear how thermal TGP will affect species responses over the long term.…”

Conservation biology meets evo‐devo: How understanding the emergence of variation can inform its management

“…Along these lines is the idea of evolutionary rescue, whereby a population or species can escape extinction through an evolutionary response. As discussed by Harmon and Pfennig (2021), this approach can be expanded to include “plastic rescue” where a plastic response can buy time for a population to persist and evolve, and in some cases could involve transgenerational responses that provide adaptive variation in the face of environmental change. However, Harmon and Pfennig (2021) provide a balanced perspective on the potential for transgenerational plasticity to be used in conservation.…”

“…As discussed by Harmon and Pfennig (2021), this approach can be expanded to include “plastic rescue” where a plastic response can buy time for a population to persist and evolve, and in some cases could involve transgenerational responses that provide adaptive variation in the face of environmental change. However, Harmon and Pfennig (2021) provide a balanced perspective on the potential for transgenerational plasticity to be used in conservation. In some cases, it may simply be the case that a species is too long‐lived to provide such responses in a timeframe that keeps pace with environmental change, or given that transgenerational plasticity may sometimes cause negative consequences it may be desirable to avoid its induction.…”

Transgenerational plasticity alters parasite fitness in changing environments

“…Moreover, phenotypic plasticity can facilitate rapid evolutionary processes, including by buying time for genetic adaptations to occur (Mousseau and Fox, 1998 ; Sun et al ., 2020 ). This can be particularly true when a plastic response to environmental changes can be passed from one generation to the next, something known as transgenerational plasticity or maternal effects (Harmon and Pfennig, 2021 ). Transgenerational plasticity has been demonstrated in many taxa; often, previous generations ‘prime’ their offspring for environmental conditions that match those of maternal generations (Mousseau and Fox, 1998 ; Burgess and Marshall, 2014 ).…”