heating. The temperature increase of the head is due to passive conduction, while the abdomen is due to physiological heat transfer throughout the body. Xylocopa have circulatory anatomy like honeybees and bumblebees. Like bumblebees, they have an aortic loop through the flight muscles that acts as a cooling coil allowing heat transfer to the blood, head, and abdomen. Carpenter bees have large heads, which present a larger surface area for convective cooling. The abdomen is also "well-suited for rapid convective heat loss because it is flattened dorso-ventral, and uninsulated". Physiological heat transfer to head or abdomen would not be apparent from body temperatures due to the rapid convective cooling, especially at high air temperatures when flight speed increases; thermoregulation involves a strong reliance on forced convection as a result of changes in flight speed, with active heat transfer to the abdomen and evaporative heat loss from the head at high temperatures. References Further reading Akamine et al. (1974). "Passion fruit culture in Hawaii". Agricultural Economics Circular; AEC-345. Honolulu (HI): University of Hawaii. Hurd, Jr., Paul (1955). "The Carpenter Bees of California (Hymenoptera: Apoidea)". Bulletin of the California Insect Survey. Berkeley: University of California Press. 4 (2). Nishida, Toshiyuki (1963). "Ecology of the pollinators of passion fruit". Technical Bulletin. Honolulu, HI: University of Hawaii, College of Tropical Agriculture, Hawaii Agricultural Experiment Station. 55: 1-38. Perkins, R. C. L (1899). "Hymenoptera Aculeata". In David Sharp. Fauna Hawaiiensis or the Zoology of the Sandwich (Hawaiian) Isles. London: Cambridge University Press. pp. 1–115. Tenorio, JoAnn M.; Gordon M. Nishida (1995). What's Bugging Me? Identifying and Controlling Household Pests in Hawaii. Honolulu, HI: University of Hawaii Press. pp. 74–76. . sonorina Hymenoptera of Oceania Insects of Hawaii Insects of the Philippines Introduced animals of Hawaii Insects described in 1874 Fauna of the Mariana Islands Fauna of the Northern Mariana Islands Hymenoptera of North America Insects of the United States Fauna of California Fauna of the California chaparral and woodlands Natural history of the Central Valley (California) Natural history of Arizona