Evidence for genetic isolation and local adaptation in the field cricket Gryllus campestris

We used RAD-Seq genotyping to quantify genetic divergenceamong ten populations of the field cricket Gryllus campestris in the CantabrianMountains and coastal plain in northern Spain. These populations were chosen torepresent replicate high and low altitude habitats. Our analysis identified substantial genetic divergence among populations a few tens of kilometres apart. Using reciprocalcrossing and common-garden rearing experiments to remove environmentaleffects, we found evidence for differences between our replicate high and lowaltitude populations in physiological and life-history traits. Our findingssuggest that local adaptation in a range of traits may be commonplace even inmobile invertebrates at scales of a very small fraction of species distributions.