Do cockroaches sleep?
Yes, cockroaches do sleep, if you define it that way. Cockroaches have activity rhythms, i.e. regular times in the day when they are quiet and hide away from the rest of the world as well as wakeful times when they are active, seeking food, water and a mate. The subject of cockroach activity rhythms is well represented in the scientific literature (see my cockroach bibliography). In general, most pest species of cockroaches are active (i.e. awake) during the four hours after lights-out. That is why they are often visible when you go to the refrigerator for that midnight snack or come home late from the movies. They cue on that time when you normally shut off all the lights and go to bed. That ensuing four hours of activity is enough for them to get all their important business done without the high probability of running into you. I showed, in my first published paper, that one four hour stretch of food availability was enough to get them through an entire molting cycle of about 6 days
