Effects of a temporally restricted protein supplement on the nocturnal activity of the female flesh fly (Sarcophaga crassipalpis)

While using the flesh fly (Sarcophaga crassipalpis) to examine activity behavior, we found that female flies exhibit a surprising amount of nocturnal activity during a three day period that has not been previously reported. To characterize the effect of temporally restricted protein meals on the nocturnal activity of female flies identified by the locomotor activity to light-dark cycles (LD 12:12; 25^o C), female flies were placed into translucent individual activity monitoring tubes equipped with infrared motion detectors and provisioned with water and sugar. Individual pieces of liver were placed in the tubes on days 1-2, 3-4, 5-6, or 7-8. Two controls were also run, a liver control where liver was added on days 1-8, and a control where no liver was added. When liver was added early, the transient nocturnal activity was found to occur at the previously observed days 4, 5 and 6. When liver was added in the later times, the nocturnal activity was delayed 24 hours after the addition of liver. The results reveal an interesting developmental window that influences subsequent behavior.