Melatonin is the chemical that regulates sleep/awake cycle in most animals. We show for the first time that melatonin also plays a role in division of labor in worker honey bees. It is known that young workers (nurses) work around the clock inside the hive and show no signs of sleep, but old workers (foragers) hunt for food during day time and rest at night. Here we show that nurse bees have low levels of melatonin in their head, in addition the melatonin levels do not change significantly with the circadian time. In foragers, melatonin levels are 10 to 20 times higher than in nurses. More importantly, the levels exhibit a cyclic change around the 24 hour clock. Our results suggest that melatonin may regulate not only the sleep/work cycle, but also the behavioral development in worker honey bees.
Species 1: Hymenoptera Apida Apis mellifera (honey bee)
Keywords: division of labor, circadian rhythm, behavioral development
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA