In this beautifully illustrated lesson from TED Ed, science writer and educator Carl Zimmer explains some answers to the question, How did feathers evolve

From his article in National Geographic: 

Most of us will never get to see nature’s greatest marvels in person. We won’t get a glimpse of a colossal squid’s eye, as big as a basketball. The closest we’ll get to a narwhal’s unicornlike tusk is a photograph. But there is one natural wonder that just about all of us can see, simply by stepping outside: dinosaurs using their feathers to fly.

With animation by Armella Leung, see how today’s birds are related to the dinosaurs of the past, and how fossils with feathers have helped us understand that connection.

Related viewing: evolution, dinosaursbirdsflying, and a robot that flies like a bird.