Circadian control of larval growth rate in Sarcophaga argyrostoma.

Larvae of the flesh fly, Sarcophaga argyrostoma, were reared in a range of environmental light cycles with periods from 21 to 72 hr, and containing either 12, 14, or 16 hr of white light. The mean length of larval development varied cyclically with the period of the driving light cycle. Protracted development occurred when the larvae were "driven" by light cycles containing a "short day" (12 hr of light) at periods close to their natural circadian frequency (about 24 hr) or multiples thereof. More rapid development occurred when the larvae were "driven" by 24-hr light cycles containing a "long day" (14 or 16 hr of light), or at periods far from their natural frequency (e.g., 36 or 60 hr).