Birds have long been our inspiration for flight, and researchers at Princeton University have found a new trick in their arsenal: covert feathers. These small feathers on top of birds’ wings lay ...

But there's more to bird flight than strong wings and hollow bones. One secret lies in their covert feathers—layers of small feathers that cover the wing’s base and shift during tricky ...

This is a type of bird that lives in the neotropics of what is now Guatemala. Adult males grow two or three long, upper-tail, covert feathers that are this emerald green that also shades into gold or ...