Ecological and Mutation-Order Speciation in Senecio.

ABSTRACT: Natural selection shapes how new species arise, yet the mechanisms that generate reproductive barriers remain actively debated. Although ecological divergence in contrasting environments and mutation-order processes in similar environments are often viewed as distinct speciation mechanisms, we show they can occur simultaneously and act as part of a continuum of selective pressures. In the Senecio lautus species complex, Dune and Headland ecotypes have evolved repeatedly along the Australian coastline. Through crossing experiments and field studies, we find that divergent natural selection promotes strong reproductive isolation between the Dune and Headland ecotypes. While uniform selection maintains reproductive compatibility among ecologically similar Dune populations, geographically dist

SUBMITTER: James ME 

PROVIDER: S-EPMC12617340 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature