Thermoregulatory physiology of the carpenter bee,Xylocopa varipuncta
The carpenter beesXylocopa varipuncta maintain thoracic temperatures of 33.0°C to 46.5°C during continuous free flight from 12°C to 40°C. Since the thoracic temperature excess is not constant (decreasing from 24°C at low air temperatures to 6°C at high) the bees are thermoregulating. We document physiological transfer of relatively large amounts of heat to the abdomen and to the head during pre-flight warm-up and during artificial thoracic heating. Most of the temperature increase of the head is due to passive conduction, while that of the abdomen is due to active physiological heat transfer despite a series of convolutions of the aorta in the petiole that anatomically conform to a counter-current heat exchanger. Although the thermoregulatory mechanisms during flight are far from clarified, our data suggest that thermoregulation involves a strong reliance on active convective cooling through increased flight speed.
KeywordsHeat Exchanger Heat Transfer Flight Speed Temperature Excess Convective Cool
Unable to display preview. Download preview PDF.
- Bartholomew GA, Heinrich B (1973) A field study of flight temperatures in moths in relation to body mass and wing loading. J Exp Biol 58:123–135Google Scholar
- Bartholomew GA, Heinrich B (1978) Endothermy in African dung beetles during flight, ball making, and ball rolling. J Exp Biol 73:65–83Google Scholar
- Casey TM (1982) Thermoregulation and control of head temperature in the sphinx moth,Manduca sexta. J Exp Biol 101:1–15Google Scholar
- Chappell MA (1982) Temperature regulation of carpenter bees (Xylocopa californica) foraging in the Colorado desert of southern California. Physiol Zool 55:267–280Google Scholar
- Gerling D, Hefetz A (1981) The ecology of the carpenter bee,Xylocopa sulcatipes Maa in Israel. In: Shural H, Balabon ISS (eds) Developments in arid zone ecology and environmental quality. Philadelphia, pp 71–74Google Scholar
- Heinrich B (1976) Heat exchange in relation to blood flow between thorax and abdomen in bumblebees. J Exp Biol 64:561–585Google Scholar
- Heinrich B (1980) Mechanisms of body temperature regulation in honeybees,Apis mellifera. J Exp Biol 85:61–87Google Scholar
- Nicolson SW, Louw GN (1982) Simultaneous measurement of evaporative water loss, oxygen consumption and thoracic temperature during flight in a carpenter bee. J Exp Zool 222:287–296Google Scholar
- Snodgrass RE (1925) Anatomy and physiology of the honeybee. McGraw-Hill, New York LondonGoogle Scholar
- Wille A (1958) A comparative study of the dorsal vessel of bees. Ann Entomal Soc Am 51:538–546Google Scholar