You are in the floodplains of China, 160 million years ago.

The air in the Jurassic fern forest was humid, filled with the scent of damp earth and cycads. You froze as a shadow passed over the canopy, not from above, but from a creature moving quietly through the undergrowth.

It wasn't a giant, towering sauropod you are expecting. Instead, a Shunosaurus—only about 30 feet long—emerged into a clearing, using its surprisingly short neck to browse on low-hanging vegetation. Its neck was thick, lacking the slender elegance of its later relatives. As it fed, it seemed deliberate, almost gentle.

Then you saw its secret weapon. As the Shunosaurus shifted its weight to reach a higher branch, its tail swung, revealing a bony, spiked club at the end. The structure was impressive, boasting two pairs of sharp, osteoderm spikes designed to keep predators at bay. The Shunosaurus continues its slow, methodical feeding, almost oblivious to your presence…