Skip to main content

Advertisement

Table 1 Measured no-beam metabolic rates and absorbed powers under x-ray irradiation (25 keV, 80 μW/mm2) for the four species studied.

From: Real-time phase-contrast x-ray imaging: a new technique for the study of animal form and function

Species Measured metabolic rate (no-beam, μW) Measured absorbed power (μW)
Grasshopper (adult) 2772 ± 248 (N = 2, 1250.0 ± 2.8 mg) 83.5 (head, N = 1, 1258.8 mg)
Grasshopper (juvenile) 230 ± 65 (N = 1, 64.3 mg) 26.0 (head, N = 1, 75.1 mg)
Beetle 441 ± 184 (N = 20, 46.6 ± 9.2 mg) 13.0 (head, N = 2, 40.1 mg)
Ant 127 ± 62 (N = 59, 21.4 ± 8.3 mg) 11.7 (head, N = 2, 19.2 ± 5.0 mg)
15.0 (thorax, N = 2, 19.2 ± 5.0 mg)
33.8 (abdomen, N = 2, 19.2 ± 5.0 mg)
Fruit fly 31 ± 9 (N = 28, 1.4 ± 0.3 mg) 1.3 (head, N = 2)
  1. Except for grasshoppers, reported metabolic rate measurements are averages of all available no-beam CO2 recordings for each of the four species. For grasshoppers, metabolic rates were not averaged due to the wide mass distribution. Conversion from CO2 output to metabolic rate assumed an energy equivalence of 20.1, 24.5, 27.6 and 21.2 J/ml of CO2 for grasshoppers [37], beetles [38], ants [39], and fruit flies [40]. Except for grasshoppers and ant abdomen, the beam was larger than the part of the animal being irradiated. Under nominal beam intensities, the absorbed power due to the x-ray irradiation was less than 20% of the unirradiated metabolic rate. Values are mean ± SD.