The symmetry of longevity.

We tested the hypothesis that relatively symmetrical flies live longer. Vein measurements on the left and right wings from the same individual were used to characterize bilateral symmetry in relationship to age-specific survival in defined cohorts. A longitudinal cohort study supported the hypothesis of a correlation between bilateral symmetry and longevity. For another type of experiment, wings were removed from females and males at approximately the beginning of adult life. Thus, there would be no effect of wings per se on adult survival. These wings were measured to characterize bilateral asymmetry, and the day of death of each dewinged individual was determined. Wing symmetry of females and males proved to be a statistically significant predictor of life span, especially for males.