You are in the dry swamplands of North America, 280 million years ago.

The humid, swampy air of the early Permian period still holds the cool of the dusk. You push aside a large, palm-like frond, and the noise of the swamp suddenly drops.

There, in a small clearing of dry, packed mud, lies a monster. It’s huge—nearly twelve feet from snout to tail—with a massive, sun-bleached sail of skin and bone jutting from its back. It is curled around a mound of rotting vegetation, the nest of a Dimetrodon.

It is asleep, but its breathing is heavy, a slow, rattling hiss that shakes its jaw. The great sail is tilted toward the weak sun filtering through the canopy, absorbing heat to wake its muscles. You are only ten feet away…

Do you try to sneak around the nest, or do you back away slowly?