Sexual differences for emigration behavior in natural populations of Drosophila melanogaster.

Evolutionary biology considers migration behavior as central in genetic structure of populations and speciation. Here we report on emigration patterns in Drosophila melanogaster behavior under laboratory conditions. For this study, a special apparatus was employed that includes a few important changes in its design and size compared with other known systems. The results presented in this paper were obtained on flies derived from natural populations of two contrasting climatic and geographical regions, from mesic northern and xeric southern parts of Israel. Highly significant difference between sexes in emigration activity was found for both localities. Emigration activity of females appeared to be higher than that of males. We also found that the flies' geographic origin affects emigration behavior (flies from a relatively closed natural system seem to display lower emigration ability than those from an open habitat), although broader sampling from various habitats is needed to confirm these results.