"Putting Flesh on Bone", explores what the animals looked like and how they behaved when they were alive. Some of the fossils are preserved in remarkable detail so that you can see the outlines of their flesh and the contents of their stomachs. Fur is clearly visible around a pterosaur fossil and the large breastbone suggests substantial flight muscles allowing powerful flight rather than just gliding. We visit the Smithsonian Institute where they have made a half-sized pterosaur model (large full-sized fossils can range from 35 to 50 feet wing-spans) to try to work out how the real giants of the air could fly.