Fig. 6.1.

Schematic overview of locomotor activity of the German cockroach. Tick marks represent the intensity of locomotor activity over 60 hours for each stage shown on the left. In males, the locomotor activity is strongly synchronised with scotophase (night), with peak activity in the early three to six hours of scotophase. Female 1 represents females before the oocytes begin to mature. Female 2 represents females with maturing oocytes, which tend to be active in both photophase and scotophase. Female 3 represents mated females carrying oothecae. Low locomotor activity is related to low foraging and feeding activity until just before the eggs hatch. Female 4 represents locomotor activity of females after dropping the oothecae and before the oocytes mature. Early instars: In 2nd–3rd instars, circadian clock-related genes are expressed, but the nymphs do not express a clear daily locomotor activity. Late instars: 4th–6th instars exhibit daily locomotor activity similar to adult males. Source: Schematics were based on Metzger (1995), Lee (2005) and references therein.