Maximum thermal tolerance trades off with chronic tolerance of high temperature in contrasting thermal populations of .

Thermal adaptation theory predicts that thermal specialists evolve in environments with low temporal and high spatial thermal variation, whereas thermal generalists are favored in environments with high temporal and low spatial variation. The thermal environment of many organisms is predicted to change with globally increasing temperatures and thermal specialists are presumably at higher risk than thermal generalists. Here we investigated critical thermal maximum (CT ) and preferred temperature () in populations of the common pond snail () originating from a small-scale system of geothermal springs in northern Iceland, where stable cold (ca.

AFLPs and mitochondrial haplotypes reveal local adaptation to extreme thermal environments in a freshwater gastropod.

The way environmental variation shapes neutral and adaptive genetic variation in natural populations is a key issue in evolutionary biology. Genome scans allow the identification of the genetic basis of local adaptation without previous knowledge of genetic variation or traits under selection. Candidate loci for divergent adaptation are expected to show higher FST than neutral loci influenced solely by random genetic drift, migration and mutation.