You are in the desert forests of South America, 225 million years ago.

The air in the Late Triassic Argentine basin was thick and humid, smelling of damp earth and cycads. You were trekking the forest when the ground vibrated. Breaking through the dense foliage to your left, the sheer scale of the creature hit you.

It was a Riojasaurus. It wasn’t a towering skyscraper like the later sauropods, but it was massive—a bulky, thirty-foot herbivore with thick, pillar-like legs. Its long neck stretched high to graze from a tree, swaying gracefully despite its heavy, quadrapedal gait.

You watched, frozen, as it lowered its head, revealing leaf-shaped teeth perfectly suited for the tough vegetation. You were struck by its sheer size, yet it seemed entirely unaware of your presence, a gentle, giant plant-eater moving through its sun-scorched, tropical world. You couldn't help but look up at the long, claw-tipped fingers on its massive forelimbs—a fascinating mix of old and new evolutionary traits.