Fine-scale biodiversity of Drosophilidae in "Evolution Canyon" at the Lower Nahal Oren microsite, Israel

The patterns of microscale biodiversity differentiation in fruit flies were studied at "Evolution Canyon", Lower Nahal Oren, Mt. Carmel, Israel. In al l, 9 species were found at the microsite. Species richness per sample and t otal sample abundance were higher on the more stressful and climatically fl uctuating south-facing slope (SFS) compared with the mild and less climatic ally stressful north-facing slope (NFS). Two sibling species, Drosophila si mulans and. melanogaster were found temporally quasi-exclusive, but a few h ybrid males were found. Significant interslope gene differences were found in Zaprionus tuberculatus and D. simulans. They corroborated our previous r esults showing significant interslope differences in mutation and recombina tion rate, behavioral variability, adaptive complexes, fluctuating asymmetr y, and mate choice. We were able to demonstrate the complex pattern of diff erences on the taxonomic, genetic, morphological, and behavioral levels of biodiversity at a distance of only 100 m. The main differentiating cause se ems to be microclimate selection that overcomes the homogenizing effect of migration.