You are in the floodplains of South America, 70 million years ago.

The sun was beginning to dip below the horizon of the late Cretaceous landscape, turning the humid haze into a vibrant orange, when the shadow fell over you. It was not a cloud. You froze, crouching beside a massive, fern-like plant, as the air filled with a sound like ripping canvas—the beating wings of a giant.

It landed ten meters away, folding its impossibly long, stiff wings like a collapsible tent. This was an Aerotitan, a creature that dwarfed the trees around it. Its narrow, spear-like beak, easily as long as you are tall, swung your way. The pterosaur stepped forward with a strange, high-stepping gait, its knuckle-walking gait, and gave a low, resonant chuff. The eyes, dark and intelligent, seemed to look right through you, assessing…