The field of flight and the evolution of feathers have always given interesting discoveries and theories. The origination of feathers and the history of how feathers were evolved have resulted into many theories. The modern view of feathers illustrates that "birds" are the torch bearers of the field of flight.
But there are many contradictions of how the feathers evolved and the use of feathers by these animals. Initially the mechanism of flight was studied and dinosaur fossils were observed to have feathers. "Avian feathers are a premier example of a complex evolutionary novelty." In the beginning these feathers were thought to be made of scales but later the feathers were known and defined to be tubular. According to Richard Prum, feathers evolved in stages.
The tubular structure modifies into at first shorter and then much complex net of feathers. Along with the nature and formation of feathers, scientists also worked on the shape and aerodynamics of these feathers. It appeared that the shape of feathers resembled that of branches of trees. The feathers had the ability to rejoin as if possessing Velcro in them. The usefulness of feathers is still debatable with different scientists coming up with different theories. The initial theories of the use of feathers list flight as function of feather.
But differing views deviated from the original concept. According to scientist the feathers were used as a sign of display and to keep the body temperature normal i.e. as insulators. These scientists believed that feathered dinosaurs used them for hunting or jumping from one tree to another, in order to catch their prey. These huge dinosaurs then evolved into lighter ones, suiting the changing environment, thus eventually using their feathers as wings.