On December 17 in 1903, the Wright brothers achieved what humans had dreamed about since the earliest days of our species: soaring through the air. For millennia, visionaries watched birds take wing and wondered how they might do the same. Notes and inspiration from bird flight were integral in helping people finally achieve the goal, but our version of flying — as well as how we got there — contrasts starkly with that of birds.

While human flight came about through intense focus on a singular goal, flight in birds evolved incrementally over millions of years without direction. The path to modern birds was full of forks, twists and dead-ends.