Infrared thermal images show that the toucan's beak heats up when the surrounding temperature rises. Image: Fraunhoefer Institute.
The toucan’s large beak makes up about a third of the bird’s body length and as much as 40 per cent of the bird’s total surface area.
Researchers at Brock University in Ontario, US, say the giant snout, whose function has eluded scientists until now, in part helps to regulate the animal’s body temperature.
Biologist Glenn Tattersall used infrared thermal images to show that the toucan’s beak rapidly warms when the ambient temperature rises. The uninsulated surface functions as a radiator, pulling heated blood to the surface of the beak and dumping excess heat into the environment.
When the temperature falls, circulation to the beak is cut off to retain warmth. Brock scientists are now investigating if temperature affects the beak size of other bird species during their development.
