Genetic divergence and one-way gene flow influence contemporary evolution and ecology of a partially migratory fish

Recent work has revealed the importance of contemporary evolution for shaping ecological outcomes. In particular, rapid evolutionary divergence between populations has been shown to impact the ecology of populations, communities, and ecosystems. While studies have focused largely on the role of adaptive divergence in generating ecologically-important variation among populations, much less is known about the role of gene flow in shaping ecological outcomes. After divergence, populations may continue to interact through gene flow, which may influence evolutionary and ecological processes. Here we investigate the role of gene flow in shaping the contemporary evolution and ecology of recently diverged populations of anadromous steelhead / resident rainbow trout (Oncorhynchus mykiss). Results show that resident rainbow trout introduced above waterfalls have diverged evolutionarily from downstream anadromous steelhead, which were the source of introductions. However, the movement of fish from..., Our study used a historical translocation of anadromous O. mykiss above waterfalls on two tributaries of a coastal California watershed as the experimental basis for studying the effects of genetic divergence and one-way gene flow on a founding population. We integrated historical records and paired surveys above and below barriers on two tributaries to explore how variation in downstream dispersal and gene flow influence the distribution of genotypes, phenotypes, and population density and size structure. We sampled O. mykiss at a number of study sites distributed across the watershed, resulting in the datasets described in the following sections.
Genetic Data
We used single nucleotide polymorphism (SNP) data at both neutral and adaptive loci to analyze patterns of population differentiation and gene flow.
Caudal fin tissue samples were extracted in 96-well plates using the DNeasy Blood and Tissue Kit following the manufacturer's specifications with the BioRobot 3000 (Qiagen Inc. Gaith..., , # Genetic divergence and one-way gene flow influence contemporary evolution and ecology of a partially migratory fish

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

Our study used a historical translocation of anadromous *O. mykiss* above waterfalls on two tributaries of a coastal California watershed as the experimental basis for studying the effects of genetic divergence and one-way gene flow on a founding population. We integrated historical records and paired surveys above and below barriers on two tributaries to explore how variation in downstream dispersal and gene flow influence the distribution of genotypes, phenotypes, and population density and size structure. We sampled *O. mykiss* at a number of study sites distributed across the watershed, resulting in the datasets described in the following sections.

## Genetic Data | `/snps.csv`

We used single nucleotide polymorphism (SNP) data at both neutral and adaptive loci to analyze patterns ...