ENERGETICS OF PEDESTRIAN LOCOMOTION IN ADULT MALE BLOWFLIES, PROTOPHORMIA-TERRAENOVAE (DIPTERA, CALLIPHORIDAE)

We describe the metabolic cost ofvoluntary pedestrian locomotion in adult male blowflies, Protophormia terraenovae (Diptera: Calliphoridae)from measurements made in a running tube. The minimum cost of transport (MCOT) based on interindividual comparisons for male blowflies is 254 J kg(-1) m(-1) (SE = 41). This value was similar to the MCOT based on intraindividual comparisons (208 J kg(-1) m(-1), SE = 72). These estimates are very near the predicted MCOT for limbed arthropods of the same size, despite the fact that unlike insects that rely exclusively on pedestrian locomotion, blowflies must carry a substantial mass of flight muscle while walking. The cost of transport for walking adult flies is almost an order of ;magnitude lower than the cost of crawling by larval flies. We also used ANCOVA to estimate the MCOT for individual flies tested at three temperatures: 28 degrees, 32 degrees, and 37 degrees C. There was no detectable temperature-by-individual interaction or temperature effect on the MCOT, and the MCOT estimated by this procedure (319 J kg(-1) m(-1), SE = 83) was statistically indistinguishable from the estimates based on intra- and interindividual comparisons at a single temperature.