Body temperature regulation
Birds, being homeothermic, are expected to keep their body temperatures within rather narrow limits. However, it turns out that individuals are able to use body temperature regulation in a seemingly adaptive way. Resident birds in regions with a pronounced winter, regularly reduce body temperature to save energy invested in thermoregulation. Since individuals only seem to use this possibility if they need to, an interesting future research question would be to estimate the costs of this physiological mechanism. Also in hot environments, birds are not strict in their thermoregulation but this time let their body temperature increase above their normal one of about 42 °C. We have found individuals to have body temperatures around 46.5 °C in hot conditions.