Scaling the fitness effects of mutations with respect to differentially adapted Arabidopsis thaliana accessions under natural conditions

Mutations are the ultimate source of genetic variation for natural selection to act upon. A major question in evolutionary biology is the extent to which new mutations can generate genetic variation under natural conditions to permit adaptive evolution over ecological time scales. Here we collected fitness data for chemically induced (ethylmethane sulfonate, EMS) mutant lines descended from two Arabidopsis thaliana ecotypes that show differential adaptation to the local environment of our common garden plot. Using a novel nonparametric Bayesian statistical approach, we found that both ecotypes accumulated substantial proportions of beneficial mutations. The poorly adapted ecotype exhibited higher mean mutational effects and higher variance in the fitness effects of mutations compared to the well-adapted ecotype. Furthermore, we predict that it takes less than 4000 generations for the fitness space of the two ecotypes to overlap through mutation accumulation, and that a single founder, t..., , , # Scaling the fitness effects of mutations with respect to differentially adapted Arabidopsis thaliana accessions under natural conditions

[https://doi.org/10.5061/dryad.2rbnzs80w](https://doi.org/10.5061/dryad.2rbnzs80w)

## Description of the data and file structure

Mutant lines were generated for Arabidopsis thaliana accessions using EMS. Lines were planted in a randomized block design in an experimental farm at the University of Maryland. Survivorship and dry weight were collected as fitness components. The data was analyzed using a novel Bayesian approach (code included).

**Description:** \"`dat_split.csv`\" The raw data of survivorship and dry weight for each accession in an Excel file.

Columns are: \"founder\" - the name for the ecotype used to generate the mutant lines, \"line\" - the mutant lines derived from the founder, \"sub\" - the sublines (A and B) derived from each founder line to account for maternal effects, \"block\" - the number of randomized block in the field experiment...