Isotopic incorporation rate, percentage of metabolism supported by oxidation of exogenous sugar, total and mass-specific oxidation rate of exogenous sugar and mass-specific oxygen consumption rate of Pallas'long-tongued nectar bats Glossophaga soricina, and hummingbirds Selasphorus rufus and Calypte anna during hovering and humans (Homo sapiens) during exercise at 50% of maximal oxygen consumption rate*
| Species . | Average Mb (g) . | k′ (% min–1) . | fexo . | Mexo (mg min–1) . | Mexo/Mb (mg min–1g–1) . | Mexo/Mb (mg min–1kg–1) . | V̇O2/Mb(ml g–1 h–1) . |
|---|---|---|---|---|---|---|---|
| Homo sapiens | 74 100±1900 (9) | – | 32.4 | 1220±70 (9) | 0.02 | 16.5 | 2.31 |
| Glossophaga soricina | 10.2±0.1 (7) | 7.0±1.7 (7) | 77.6±4.8 (7) | 3.80±0.22 (7) | 0.37±0.02 (7) | 366.8±20.8 (7) | 21.29±0.60 (7) |
| Selasphorus rufus | 3.4±0.1 (10) | 11.8±1.4 (10) | 94.7±1.5 (10) | 2.45±0.07 (10) | 0.71±0.01 (10) | 713.7±13.4 (10) | 33.70±0.45 (10) |
| Calypte anna | 4.8±0.3 (2) | 7.8±3.2 (2) | 95.5±1.5 (2) | 3.49±0.08 (2) | 0.72±0.05 (2) | 715.0±48.5 (2) | 33.36±1.76 (2) |
| Species . | Average Mb (g) . | k′ (% min–1) . | fexo . | Mexo (mg min–1) . | Mexo/Mb (mg min–1g–1) . | Mexo/Mb (mg min–1kg–1) . | V̇O2/Mb(ml g–1 h–1) . |
|---|---|---|---|---|---|---|---|
| Homo sapiens | 74 100±1900 (9) | – | 32.4 | 1220±70 (9) | 0.02 | 16.5 | 2.31 |
| Glossophaga soricina | 10.2±0.1 (7) | 7.0±1.7 (7) | 77.6±4.8 (7) | 3.80±0.22 (7) | 0.37±0.02 (7) | 366.8±20.8 (7) | 21.29±0.60 (7) |
| Selasphorus rufus | 3.4±0.1 (10) | 11.8±1.4 (10) | 94.7±1.5 (10) | 2.45±0.07 (10) | 0.71±0.01 (10) | 713.7±13.4 (10) | 33.70±0.45 (10) |
| Calypte anna | 4.8±0.3 (2) | 7.8±3.2 (2) | 95.5±1.5 (2) | 3.49±0.08 (2) | 0.72±0.05 (2) | 715.0±48.5 (2) | 33.36±1.76 (2) |
Values are means ± s.e.m. (N)
k′, isotopic incorporation rate; fexo,percentage of metabolism supported by oxidation of exogenous sugar; Mexo, total and Mexo/Mb, mass-specific oxidation rate of exogenous sugar; V̇O2/Mbmass-specific oxygen consumption rate; V̇O2max, maximal oxygen consumption rate
(Jentjens et al.,2004b)