The Spatial and Temporal Repeatability of Genomic Responses to Natural Selection as Demonstrated in Stickleback Populations Experiencing Highly Dynamic Environments

Description

Mary Kathleen Hickox and colleagues test whether natural selection repeats itself in space and time, using stickleback fish in California estuaries. Parallel evolution under shared conditions is strong evidence for selection, but studies usually examine genomic marks long after the event, and only across places. That makes it hard to pin a response on one pressure, or to split chance gaps from gaps picked by local selection.

The team used bar-built estuaries near Santa Cruz, whose settings swing with the seasons. They compared allele frequency shifts shared across places, spatial repeatability, with shifts shared across years within places, temporal repeatability. Seasonal outlier responses occurred more often than a neutral null model would predict, and repeatability fell as more estuaries had to share a response. The design catches selection in the act: repeatability is real but graded.

Catalog record

Source: https://europepmc.org/articles/PMC13545515