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Abstract Populations declining due to climate change may need to evolve to persist. While evolutionary rescue has been demonstrated in theory and the lab, its relevance to natural populations facing climate change remains unknown. Here we link rapid evolution and population dynamics in scarlet monkeyflower,Mimulus cardinalis, during an exceptional drought. We leverage whole-genome sequencing across 55 populations to identify climate-associated loci. Simultaneously we track demography and allele frequency change throughout the drought. We establish range-wide population decline during the drought, geographically variable rapid evolution, and variable population recovery that is predictable by both standing genetic variation and rapid evolution at climate-associated loci. These findings demonstrate evolutionary rescue in the wild, showing that genomic variability at adaptive, but not neutral loci, predicts population recovery. 

Herbaceous plant species have been the focus of extensive, long-term research into climate change responses, but there has been little effort to synthesize results and predicted outlooks from different model species. We summarize research on climate change responses for eight intensively-studied herbaceous plant species. We establish generalities across species, examine limitations, interrogate biases, and propose a path forward. All six forb species exhibit reduced fitness, maladaptation, and/or population declines in at least part of the range. Plasticity alone is likely not sufficient to allow adjustment to shifting climates. Most model species also have spatially-restricted dispersal that may limit genetic and evolutionary rescue. These results are surprising, given that these species are widespread, span large elevation ranges, and generally have substantial levels of genetic and phenotypic variation. The focal species have diverse life histories, reproductive strategies, and habitats, but most are native to North America. Thus, these species may poorly represent rare species, habitat specialists, or species endemic to other parts of the world. We encourage researchers to design demographic and field experiments that evaluate plant traits and fitness in contemporary and potential future conditions across the full life cycle, and that consider the effects of climate change on biotic interactions.