Flight duration and wing beat frequency in long- and short-lived Drosophila melanogaster

This study tests for differences in flight endurance of D. melanogaster populations selected for increased and decreased life span. Flight duration was measured in tethered individuals at ambient temperature and compared at a variety of low ambient humidities with flights under extreme humidity. Flight in young individuals of less than 4 days adult age was compared with that of flies of 30-50 days age. Except for very young individuals, long-lived flies flew longer under every combination of temperature, humidity and age. And finally, to test the idea that longer flight of the long-lived population could result from an artifactual reduction in flight frequency, the rate of wing beat was compared in long-lived, short-lived and F₁ populations by means of a new device that measures wing beat continuously for flights of several hours duration, with on-line microcomputer storage and analysis. These measurements indicate that the protracted flights of long-lived individuals take place at the same or a slightly higher rate than those of short-lived individuals.