MAINE SUNDAY TELEGRAM • March 13, 2022
Have you ever wondered why most birds lack feathers on their lower legs? It turns out those naked legs are designed to lose heat of a bird when it is flying. The arteries and veins of a bird’s leg are arranged as a counter-current, helping the bird lose as little heat as possible as it pumps blood to the cells of the bird’s leg to provide nutrition and oxygen. Given a bird’s arsenal of adaptations to tolerate the cold, the limiting factor for a bird is finding sufficient food. If food is adequate, a bird can scoff at the Maine winter climate. ~ Herb Wilson