The toucan beak isn’t just beautiful, it’s also an adjustable thermal radiator that the bird uses to warm and cool itself.

Researchers have discovered that the toucan can heat and cool its bill at an astonishing rate, changing its temperature by up to 18 degrees Fahrenheit degrees within a few minutes. Birds do not sweat, so they must cope with other mechanisms to deal with elevated temperatures.

Using a temperature-sensing video called infrared thermography, scientists have tracked the pattern of heat distribution across the toucan’s body under changing outside temperatures. When the bird got too hot, it released heat by sending blood to its highly vascular but uninsulated beak. In cooler weather, the toucan constricted blood vessels in its beak to conserve heat and stay warm.

Like most mammals, including humans, the toucan drops its body temperature to conserve energy while sleeping. In the time-lapse video below, a toucan heats up its bill while falling asleep, then cools it down after reaching the optimal sleeping temperature. Once it has fallen asleep, the bird also tucks its beak under its feathers, presumably to avoid unwanted heat loss. (The 48-second video compresses two hours.)



Original article here.