“No, silly,” Jahna said. Seeing her brother’s fear was real, she put her arms around him. “He probably just put it in the ground when it was dead.”

But Millo was shivering. She hadn’t meant to scare him. She pushed the skull out of his sight and, to calm him, began to tell him a story.

“Listen to me now. Long, long ago, the people were like the dead. The world was dark and their eyes were dull. They lived in a camp as they do now, and they did the things they do now. But everything was dark, not real, like shadows. One day a young man came to the camp. He was like the dead too, but he was curious — different. He liked to go fishing and hunting. But he would always go deeper into the sea than anybody else. The people wondered why…”

As she crooned the story, Millo relaxed against her, sinking into sleep just as the sun sank into the ocean. Even the big bonehead was dozing, she saw, slumped against a wall, belching softly. Perhaps he was listening too.

Her story was a creation myth, a legend already more than twenty thousand years old. Such tales — which said that Jahna’s group were the pinnacle of creation, that theirs was the only right way, and that all others were less than human — taught the people to care passionately about themselves, their kin, and a few treasured ideals.

But to the exclusion of all other humans, let alone such nonpeople as the Old Man’s kind.

“…One day they saw that the young man was with a sea lion. He was swimming in the waves with it. And he was making love to it. Enraged, the people drove out the young man, and they caught the sea lion. But when they butchered it they found a fish inside, in its womb. It was a fat fish.” She meant a eulachon. “The fish had been fathered by the young man. He was neither person nor fish, but something different. So the people threw the fish-boy on their fire. His head burst into flames and made a bright light that dazzled them. So the fish-boy flew into the sky. The sky was dark, of course. There he sought the place where the light was hiding, because the fish-boy thought he could trick the light to come down to the dark world. And then…”

And then her father walked in.

The Old Man was a Neandertal.

His kind had endured in Europe, through the savage swings of the Ice Age, for a quarter of a million years. In their way the robust folk had been supremely successful. They had found ways to live here in the most marginal of environments, on the edge of the world, where the climate was not only harsh but could vary treacherously fast, where animal and plant resources were sparse and prone to fluctuate unpredictably.

For a long time they had even been able to resist the children of Mother. During warming pulses the new humans pushed into Europe from the south. But with their stocky bodies and big air-warming sinuses and heavily meat-tolerant digestion systems, the robusts were better able to withstand the cold than the moderns. And their bearlike builds made them formidable infighters: tough opponents for the humans, better technology or not. Then, when the cold intensified again, the moderns would retreat back to the south, and the robust folk could repopulate their old lands.

This had happened over and over. In southern Europe and the Middle East there were caves and other sites where layers of human detritus were overlaid by Neandertal waste, only to be reoccupied by humans again.

But during the last thaw the moderns had looked again to Europe and Asia. They had advanced, culturally and technologically. And this time the robusts hadn’t been able to resist. Gradually the robusts were eliminated across much of Asia, and pushed back into their chill fortress, Europe.

The Old Man had been ten years old when skinny hunters had first stumbled on his people’s encampment.

The camp had been constructed on a south-facing riverbank a few kilometers back from the cliff top, placed close to the trails of the great herds of migrant herbivores that washed over the landscape. They lived here as they had always lived, waiting for the seasons to bring the herds to their porch. The riverbank had been a good place.

Until the skinnies came.

It wasn’t a war. The engagement had been much more complex, messy, and protracted than that.

At first there had even been a kind of trade, as the skinnies swapped sea produce for meat from the giant animals the people were able to kill with their thrusting spears and great strength. But the skinnies seemed to want more and more. And, as they came roaming over the land with their strange slender spears and the bits of wood that would hurl them far, the skinny hunters were just too effective. Soon the animals grew wary and changed their habits. No longer did they follow their old trails and gather at the lakes and ponds and rivers, and the robusts had to roam far in search of the prey that had once come to them.

Meanwhile, for the Old Man’s folk, contact with the skinnies had inevitably increased.

There had been sex, willing and unwilling. There had been fights. If you got a skinny in close combat you could crush his or her spine, or smash that big bubble skull with a single punch. But the skinnies wouldn’t close with you. They struck from a distance, with their hard-thrown spears and flying arrows. And the people could not strike back: even after tens of millennia of living alongside the skinnies the descendants of Pebble had failed to copy even their simplest innovations. Besides, as the skinnies ran around you hollering to each other in their birdlike voices — with their elaborately painted clothes and bodies, and with a restless blur of speed as if the world was too slow, too static for them — it was hard to even see them. You couldn’t fight what you couldn’t see.

Eventually there had come a day when the skinnies had decided they wanted the place where the Old Man’s people lived, their riverbank home.

It had been simple for them. They had killed most of the men, and some of the women. They chased the survivors away, to forage for themselves as best they could. By the time the Old Man returned, from a solo expedition to the river, the skinnies were burning the huts and cleaning out the caves, places where the Old Man’s grandmothers’ bones lay a hundred generations deep.

After that, the people wandered aimlessly, sedentary creatures forced to be nomads. If they tried to set up a new base, the skinnies would quickly break it up again. Many of them starved.

At last, inevitably, they had been drawn to the camps of the skinnies. Even now, many of his kind still lived on, but they were like the boneheads who followed Jahna’s encampment, where they lived like rats on garbage, and even then only as long as the skinnies tolerated them. Their eventual fate was already obvious.

All save the Old Man. The Old Man had stayed away from the dismal skinny places. He was not the last of his kind. But he was the last to live as his ancestors had before the coming of the moderns. He was the last to live free.

When Mother had died, just sixty thousand years before the birth of Christ, there had still been many different kinds of people in the world. There had been Mother’s humanlike people in parts of Africa. In Europe and western Asia lived robust folk like Pebble, like Neandertals. In eastern Asia there were still bands of the skinny, small-brained walkers, the Homo erectus types. The old hominid complexity had reigned still, with many variants and subspecies and even hybrids of the different types.

With the revolution started in Mother’s generation, with the great expansion that had followed, all this changed. It was not genocide; it was not planned. It was a matter of ecology. The different forms of humans were competing for the same resources. All over the world there had been a wave of extinctions — human extinctions — a wave of last contacts, of regret-free good-byes, as one hominid species after another succumbed to the dark. For a time the last of the walkers had hung on in isolation on Indonesian islands, still living much as Far had, so long ago. But when the sea levels dropped once more, the bridges to the mainland were reestablished, and the moderns crossed over — and for the walkers, after a long and static history spanning some two million years, the game was up.