Wednesday, 20 November 2002 - 10:00 AM

This presentation is part of : Apiculture and Social Insects (Ants et al.)

Field validation of laboratory-derived locomotion energetics in ants

John R.B. Lighton, University of Nevada at Las Vegas and Sable Systems International, Biological Sciences, 8445 Westwind Rd, Las Vegas, NV and Francis D. Duncan, University of Witwaterstrand, Department of Zoology, Private Bag 3, PO Wits, South Africa.

Tradiotionally, the energy cost of activities central to overall fitness in most animals, such as pedestrian locomotion, is measured in the laboratory. It is then extrapolated to field conditions for modeling or hypothesis-testing purposes. We present the first accurate, direct, in situ validation of these extrapolations made on undisturbed animals, using harvester ants (Messor pergandei). We measured the metabolic rate (MR) of a natural, undisturbed ant trail foraging through a respirometer chamber in the field, after measuring their energetic parameters in the laboratory using a running tube. From temperature, ant numbers, ant masses and foraging speeds (obtained through video analysis), we predicted trail MRs from separately obtained laboratory data and compared them to measured field trail MRs. No significant difference was found between actual field values and values predicted from equations produced from data acquired in the laboratory. Our results therefore serve to validate two unusual findings in ants, which would otherwise be troubling to extrapolate to field conditions: That their extrapolated MR at zero running speed does not differ from standard (resting) metabolic rate, and that their costs of transport are far lower than predicted on the basis of current allometric equations.

Species 1: Messor Pergandei (harvester ant)
Keywords: energetics, ants

Back to Apiculture and Social Insects (Ants et al.)
Back to Ten-Minute Papers, Section Ca, Cb, Cc, Cd, Ce, and Cf
Back to The 2002 ESA Annual Meeting and Exhibition