2021/04/04 by Luis J. Chueca, Tilman Schell, Markus Pfenninger · 1 citation
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · Environmental Science · #Mollusks and Parasites Studies #Genetic diversity and population structure #Aquatic Invertebrate Ecology and Behavior
paper · pdf · doi:10.1098/rstb.2020.0156
openalex publication_date 2021/04/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Abstract Despite the global biodiversity of terrestrial gastropods and their ecological and economic importance, the genomic basis of ecological adaptation and speciation in land snail taxa is still largely unknown. Here, we combined whole-genome re-sequencing with population genomics to evaluate the historical demography and the speciation process of two closely related species of land snails from western Europe, Candidula unifasciata and C. rugosiuscula. Historical demographic analysis indicated fluctuations in the size of ancestral populations, probably driven by Pleistocene climatic fluctuations. Although the current population distributions of both species do not overlap, our approximate Bayesian computation model selection approach on several speciation scenarios suggested that gene flow has occurred throughout the divergence process until recently. Positively selected genes diverging early in the process were associated with intragenomic and cyto-nuclear incompatibilities, respectively, potentially fostering reproductive isolation as well as ecological divergence. Our results suggested that the speciation between species entails complex processes involving both gene flow and ecological speciation, and that further research based on whole-genome data can provide valuable understanding on species divergence. This article is part of the Theo Murphy meeting issue ‘Molluscan genomics: broad insights and future directions for a neglected phylum’.