You are in the scrublands of South Africa, 248 million years ago.

The air in the Middle Triassic Pangea was heavy, smelling of arid earth and unfamiliar conifers. You were crouched behind a rocky outcrop, watching a small herd of Lystrosaurus foraging near a dry riverbed. That’s when the vegetation parted, and the Cynognathus appeared.

It was about two meters long, stocky and low to the ground, with a disproportionately massive skull. It looked unnervingly like a bear-sized wolf, with fur, or at least stiff hairs, covering a dog-like body.

It stood on semi-sprawling legs, its long tail flickering as it sniffed the air. Then it locked eyes with you. There was no blank reptile stare; this was the intelligent, predatory gaze of a stem-mammal, and it was assessing you.

You didn’t move. It lowered its head, revealing the differentiated teeth—incisors and large canines. It didn’t look like a mindless beast, but rather a calculating predator that specialized in shearing flesh. As it took a step forward, the sheer menace of this early synapsid was palpable, a reminder that before dinosaurs, creatures like this ruled the southern Pangea continent…