Before true flight evolved, 'wings' and other long feathers must have dragged and snagged - quite a disadvantage. So what adaptive advantages led to the development Of flight feathers? Birds make flying look easy. We see in them a natural grace that belies the effort, the complex aerodynamics and the long evolutionary history involved. The origins of bird flight lie in the Mesozoic Era (about 250-65 million years ago), closely linked with the evolution of another iconic bird trait: feathers. For generations, ornithology textbooks taught that feathers evolved when elongate scales frayed from the edges to become more lightweight and aerodynamic.
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