Microsatellite analysis of Drosophila melanogaster populations along a microclimatic contrast at lower Nahel Oren canyon, Mount Carmel, Israel.

Drosophila melanogaster populations collected at the south-facing slope (SFS) and north-facing slope (NFS) of lower Nahel Oren canyon, Mount Carmel, Israel display significant differences in survival and longevity at temperature, drought, and starvation stresses. Furthermore, significant assortative mating was previously observed between populations of the two slopes. We used a set of 48 microsatellite markers to analyze patterns of genetic differentiation between D. melanogaster populations from both slopes and D. simulans. Consistent with previous reports, we found D. simulans to be well differentiated from D. melanogaster. Genetic differentiation between SFS and NFS D. melanogaster populations was low (F(ST) = 0.0012). Also a tree of individuals based on the proportion of shared alleles and a model-based clustering method provided no evidence for population substructuring.