Abstract: Honeybees are ectotherms that have the specific ability to control their body temperature to match environmental change. Honeybees, such as Apis mellifera L., can flex and extend their abdomen to transfer heat with the environment. Their folded intersegmental membranes, which are distributed in the segments of their abdomen, play key roles in heat transfer with abdominal movements. In this study, a temperature-controlled device was established to simulate varying ambient temperature and the abdominal behaviors of honeybee were investigated. Experimental results show that the folded intersegmental membranes make a considerable difference on the bees’ heat transfer ability. Bees can achieve temperature equilibrium by moving their abdomen, in this way bees increase convection to achieve temperature equilibrium. The higher the experimental temperature was, the faster the membrane moved and the shorter time required to reach heat balance. The function of folded intersegmental membranes on heat transfer was further elucidated by proposing a convective heat transfer model. The study on thermoregulation mechanism of honeybee abdomen helps explain its strong adaptability to the external environment as well as its defensive behavior against foreign invaders.

Key words: folded intersegmental membrane, honeybee, temperature variation, heat transfer