Today, not far from the ragged fringe of the forest, an antelope carcass lay on the ground. The animal was not long dead—its wounds still oozed sticky blood—but the lions had already eaten their fill, and the other scavengers of the plain, the hyenas and the birds, had yet to discover it.

Seeker stood upright, unfolding her long legs, and peered around.

Seeker was an ape. Her body, thickly covered with dense black hair, was little more than a meter tall. Carrying little fat, her skin was slack. Her face was pulled forward into a muzzle, and her limbs were relics of an arboreal past: she had long arms, short legs. She looked very like a chimpanzee, in fact, but the split of her kind from those cousins of the deeper forest already lay some three million years in the past. Seeker stood comfortably upright, a true biped, her hips and pelvis more human than any chimp’s.

Seeker’s kind were scavengers, and not particularly effective ones. But they had advantages that no other animal in the world possessed. Cocooned in the unchanging forest, no chimp would ever make a tool as complex as the crude but laboriously crafted axe Seeker held in her fingers. And there was something in her eyes, a spark, beyond any other ape.

There was no sign of immediate danger. She stepped boldly out into the sun, her child clinging to her chest. One by one, timidly, walking upright or knuckle-walking, the rest of the troop followed her.

The infant squealed and pinched her mother’s fur painfully. Seeker’s kind had no names—these creatures’ language was still little more sophisticated than the songs of birds—but since she had been born, this baby, Seeker’s second, had been ferociously strong in the way she clung onto her mother, and Seeker thought of her as something like “Grasper.”

Burdened by the child, Seeker was among the last of the troop to reach the fallen antelope, and the others were already hacking with their chipped stones at the cartilage and skin that connected the animal’s limbs to its body.