Rapid evolution by spontaneous mutation increases genetic diversity facilitating plant population survival

Using a mechanistic eco-evolutionary trait-based neighborhood-model, we quantify the impact of mutations on spatial interactions to better understand the potential effect of niche evolution through mutations on the population dynamics of Arabidopsis thaliana. We use 100 twenty-fifth generation mutation accumulation (MA) lines (genotypes) derived from one founder genotype to study mutational effects on neighbor responses in a field experiment. We created individual-based maps (15,000 individuals), including phenotypic variation, to quantify mutational effects within genotypes versus between genotypes on reproduction and survival. At small-scale, survival is enhanced but reproduction is decreased when a genotype is surrounded by different genotypes. At large-scale, seed set is facilitated by different genotypes while the same genotype has either no effect or negative effects. Mutations may provide a mechanism for plants to quickly evolve niches and may drive competition, facilitation and selection with profound consequences for future population and community dynamics.