Archaeologists at the University of Maryland believe they have discovered the missing link in the chain between early downy feathers and the flight-capable feathers found on modern birds. What makes this feather so interesting? The shaft. Early feathers grew in tufts on a dinosaur's skin. This "proto-feather" found on a newly-discovered type of therizinosaur, Beipiaosaurus, shows the development of a central shaft, off of which the feathers form tufts. Many believe these tufts were used for warmth, either to keep warm or to keep their eggs warm, much like birds of today.
That's not even the most interesting thing about this fascinating group of dinosaurs. Their bodies had an odd feature combination. They had specialized hands and feet, giant claws, and were herbiferous, though related to meat-eaters. The Beipiaosaurus fossil included its skull, which should go a long way toward finding exactly where this wacky group of dinosaurs, called the therizinosaurs, fits in the evolutionary tree, according to Popular Science magazine.