Rapid adaptive evolution to drought in a subset of plant traits in a large‐scale climate change experiment

Abstract

Rapid evolution of traits and of plasticity may enable adaptation to climate change, yet solid experimental evidence under natural conditions is scarce. Here, we imposed rainfall manipulations (+30%, control, À30%) for 10 years on entire natural plant communities in two Eastern Mediterranean sites. Additional sites along a natural rainfall gradient and selection analyses in a greenhouse assessed whether potential responses were adaptive. In both sites, our annual target species Biscutella didyma consistently evolved earlier phenology and higher reproductive allocation under drought. Multiple arguments suggest that this response was adaptive: it aligned with theory, corresponding trait shifts along the natural rainfall gradient, and selection analyses under differential watering in the greenhouse. However, another seven candidate traits did not evolve, and there was little support for evolution of plasticity. Our results provide compelling evidence for rapid adaptive evolution under climate change. Yet, several non-evolving traits may indicate potential constraints to full adaptation.

Rapid evolution in response to climate-change-induced drought and its demographic and genetic controls

“…The evolution of earlier flowering observed at S22 is consistent with post-drought resurrection studies in Brassica rapa [5,33], and likely reflects a strategy of drought escape as documented in many other plant species [reviewed in 40,61,62]. Though the evolution of more rapid phenology during drier periods is not ubiquitous [see 12,14], there are several reasonable hypotheses for why flowering phenology is more likely to rapidly evolve relative to other traits.…”

Neutral and adaptive drivers of genomic change in introduced brook trout (Salvelinus fontinalis) populations revealed by pooled sequencing

“…Harbicht et al, 2014;Hecht et al, 2015;Krueger & May, 1991;Power, 1980;Rieman & Allendorf, 2001), perhaps the species may be preadapted to conditions in alpine lake environments (i.e., freezing temperatures, high elevation). Second, ~50 years since introduction (average ~19 generations) may not be enough time to generate stronger adaptive differentiation, though there is some evidence that this can happen in other invasive species across taxa (e.g., Ghalambor et al, 2015;Hendry et al, 2000;Metz et al, 2020).…”

Phylogeography of a widely distributed plant species reveals cryptic genetic lineages with parallel phenotypic responses to warming and drought conditions

“…In the future, climate change will either lead to a shift in distribution patterns in plants or will force them to adapt locally (Ahrens et al., 2020 ; Anderson & Wadgymar, 2020 ; He et al., 2019 ; Metz et al., 2020 ). The present study used a comprehensive approach including a pan‐European sampling and a greenhouse experiment on climate change adaptation paired with a population genetic analysis to understand the interaction of population genetics and current trait responses.…”