Patterns of movement and ageing in Drosophila melanogaster.

The paths of young and old Drosophila melanogaster have been photographed from the center of an arena, the release point. The results indicate that old flies do not move as far away from the release point and have more sinuous paths than young ones. A high proportion of old flies trace loops during their course, while this is the case for only a few young files. It can be argued that young flies show patterns of movement which maximize the dispersion, while old flies explore the environment in such a way as to withdraw not too far from the release point.