Metabolic rate and sexual activity in Drosophila simulans

The metabolic rates of 4-day-old Drosophila simulans females are affected by sexual activity. Virgin females have the lowest rates of metabolism, inseminated females that were separated from males had higher rates of metabolism, and females that were kept continuously in contact with males had the highest rates of metabolism. Differences between the metabolic rates of the latter two classes of females are unrelated to differences in their rates of egg laying.