You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
"Laziness" and Hypothermia as a Foraging Strategy in Flower Scarabs (Coleoptera: Scarabaeidae)
Bernd Heinrich and Elizabeth Mcclain
Vol. 59, No. 2 (Mar. - Apr., 1986), pp. 273-282
Published by: The University of Chicago Press. Sponsored by the Division of Comparative Physiology and Biochemistry, Society for Integrative and Comparative Biology
Stable URL: http://www.jstor.org/stable/30156041
Page Count: 10
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Flower scarabs can warm up endothermically from 20 C to flight temperatures near 36 C in 3 min. Despite their impressive capacity for endothermy, however, foraging beetles stop heat production immediately on landing on a flower. In addition, they seek shade within seconds of landing and allow body temperatures to follow ambient thermal conditions. Foraging beetles spend at least 98% of their time perched and feed slowly. In the laboratory, beetles that are handled or otherwise disturbed warm up repeatedly by endothermic shivering, but in the field undisturbed beetles generally warm up to fly to another flower only when they have the opportunity to warm up by basking. Unlike other large strong-flying insects so far examined, these beetles do not regulate (stabilize) their thoracic temperature in flight, and they restrict flight to a narrow range of ambient temperature. We speculate that their lack of maintenance of an elevated body temperature ("hypothermia") when not in flight and their seemingly lackadaisical foraging is related to low foraging competition leading to a minimization of energy expenditure.
Physiological Zoology © 1986 The University of Chicago Press