East African tenebrionid beetles of the species Zophosis congesta are active on sun-exposed surfaces in dry habitats during the hottest part of the day, when most other animals have retreated to protected areas. They remain on the surface at ambient temperatures up to 65°C which is 15°C above their highest tolerated body temperature. The beetles appear to regulate their body temperature behaviourally. They frequently rest and cool in the shade, and after each cooling period they remain on the sun-exposed surface until the heat influx from the environment has caused the body temperature to rise close to the lethal level. They have relatively low rates of transpiratory water loss, and appear unable to depress their body temperature by means of evaporative heat loss. The rate of metabolic production of water amounts to only about 20% of the rate of transpiratory water loss. Thus, the beetles depend strongly on water intake from dietary sources. The advantage of this type of activity pattern is probably avoidance of predators.

The thermoregulatory responses in 13 haemodynamically stable patients were evaluated over a 7-h period following coronary artery bypass graft surgery. Cutaneous vasoconstriction was defined by a forearm-to-fingertip skin temperature gradient (ΔTskin) ≥ 4°C and muscular hyperactivity was assessed by integrating the electromyographic signals (iEMG). Blood gases and lactate were measured in arterial, mixed venous and femoral venous blood. After arrival in ICU, we observed: (1) mild central hypothermia (Tc = 34.8±0.6°C) and elevated peripheral vascular resistance in all the patients; (2) ΔTskin ≥ 4°C in 11 of 13 patients that persisted until a median Tc of 37.1°C was achieved; (3) a transient increase in iEMG (±18%)was accompanied by an increase in total body O2 uptake (+28%); (4) elevated muscle O2 extraction rate(56±18% after 3 h) and lactate release. These data suggest that residual hypothermia in sedated patients safter cardiac surgery elicits appropriate thermoregulatory responses that are associated with transient O2 supply/uptake mismatch within skeletal muscles.