Evolvability and evolutionary rescue

Abstract

The survival prospects of threatened species or populations can sometimes be improved by adaptive change. Such evolutionary rescue is particularly relevant when the threat comes from changing environments, or when long‐term population persistence requires range expansion into new habitats. Conservation biologists are therefore often interested in whether or not populations or lineages show a disposition for adaptive evolution, that is, if they are evolvable. Here, we discuss four alternative perspectives that target different causes of evolvability and outline some of the key challenges those perspectives are designed to address. Standing genetic variation provides one familiar estimate of evolvability. Yet, the mere presence of genetic variation is often insufficient to predict if a population will adapt, or how it will adapt. The reason is that adaptive change not only depends on genetic variation, but also on the extent to which this genetic variation can be realized as adaptive phenotypic variation. This requires attention to developmental systems and how plasticity influences evolutionary potential. Finally, we discuss how a better understanding of the different factors that contribute to evolvability can be exploited in conservation practice.

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

“…Feiner et al (2021) offer another perspective on evolutionary rescue that focuses on evolvability. This takes note of recent advances in evolutionary biology that have focused on how adaptive variation (rather than shear amounts of heritable variation) is generated by development.…”

“…Overall, the challenge for evolvability is the prediction of responses to environmental conditions that may not currently exist. Feiner et al (2021) note however that evolvability should generally be higher in organisms that have faced an evolutionary history of environmental change. Thus, the concepts that are central to evo‐devo can be leveraged in some cases for a practical management purpose.…”

Circadian-period variation underlies the local adaptation of photoperiodism in the short-day plant Lemna aequinoctialis

“…Natural variation in phenotypic traits plays a key role in evolutionary adaptation ( Barret and Schluter, 2008 ; Alonso-Blanco et al., 2009 ; Matuszewski et al., 2015 ). However, the molecular mechanisms that generate such phenotypic variations in natural settings are still poorly understood because they are complex traits at the molecular level ( Boyle et al., 2017 ; Sella and Barton, 2019 ; Feiner et al., 2021 ).…”

Ecological constraints on highly evolvable olfactory receptor genes and morphology

“…increased evolvability. With increased variation, there is more opportunity to generate phenotypic diversity and interact with new stimuli, facilitating novel adaptive zone occupation (3,4). At the same time, rampant diversification is expected to come under constraint from ecological limits (5).…”