With their bare, sweating skin, the people were as well equipped for this hot, open dryness as any other species here. But they too began their day listlessly. They milled about their island of rock, picking at what was left of yesterday’s food.

This wasn’t a particularly rich area. The people didn’t discuss their plans — they never did, and anyhow they had no real plans — but it was obvious they shouldn’t stay here. Before long some of the men started to set off toward the water course to continue their walk to the south.

But the Brat’s condition had worsened overnight. The soles of his feet were cracked and oozing a watery pus, and when he tried to put his weight on them he cried out in pain. He wouldn’t be walking anywhere today.

Calm, Far’s grandmother, and most of the other women stayed close to the Brat. As for the men, the women just ignored their antics as they impatiently paced up and down the trail they had begun toward the south.

This conflict, all but wordless, over the day’s course was hurtful for them all. It was a genuine dilemma. The savannah was not like the bountiful, reliable forest of earlier times; you couldn’t just walk off in any random direction. Every day, in this sparse, changeable land, the people were faced with decisions about where to go to find food, water, what dangers to avoid. If they got it wrong, even once, the consequences were drastic. But the walkers had few children, and invested much effort in each one; you didn’t abandon one lightly.

At last the men gave up. Some of them returned to the rock to laze in the light of the high, hot sun. A handful of others set off under Brow’s leadership on the trail of an elephant herd, one of whose infants appeared to be limping. The rest of the men — and the women and older children — dispersed to the foraging sites they had explored yesterday.

The way these people were living — setting up a central home base, retrieving food, and sharing food and labor — was necessary. On the open plain the people had to work hard for food, and their slow-growing young extracted a high cost in care. They had to cooperate and share, one way or another. But there was no real planning. In many ways this was more like a wolf pack than any human community.

Far spent most of the morning in the same trampled thicket her mother had worked yesterday. The ground had already been thoroughly worked over, and to find new roots and fruit required much digging. Soon she was hot, dirty, and uncomfortable. She felt restless, confined, and her long legs, folded under her in the trampled dirt and debris, seemed to ache.

As noon approached, the desultory stillness of this strange, heavy day deepened. The savannah, open and free, beckoned Far, as it had done yesterday. As the emptiness in her belly diminished, the pressures of survival and familial duty were overcome by her longing to get out of here.

One spindly palm had survived the deinotheres’ attention, and it had a cluster of nuts at its top. A young man shimmied up the tree with a grace that came from his body’s deep-buried memory of earlier, greener times. Far watched his lithe torso working, and felt a peculiar ache at the base of her belly.

She came to a kind of decision. She dropped the last of the food, clambered out of the thicket, and just sprinted off to the west.

She felt a vast relief as her limbs worked, her lungs pumped, and she felt clean crisp dirt beneath her feet. For a time, as she ran without thinking, even the day’s heat seemed alleviated as the breeze of her passing cooled her skin.

Then there was a deep, menacing rumble that echoed across the sky. She pulled up, crouched, and peered around fearfully.

The bright sunlight dimmed. Thick black clouds were pouring across the sky from the east. She was startled by a flash of purplish light that lit up the clouds from within. Almost immediately there was a shattering crash and a deeper, drawn-out rumble that seemed to roll around the sky.

Looking back at the rocky outcrop, which suddenly seemed very far away, she saw the people running, gathering up their infants. Her heart hammering, Far straightened up and began to head back.

But now rain lashed down from the blackening sky. The drops were heavy enough to sting her bare skin and unprotected scalp, and they dug small craters in the dirt. The ground rapidly turned to sticky mud that clung to her feet, slowing her down.

Light flashed again, this time a great river of it that briefly connected sky to ground. Dazzled, she stumbled and fell in the mud. Shattering noise pealed around her, as if the world were falling apart.

She saw that the tall palm at the center of the trampled clearing had been split in two, and it was blazing, the flames licking at the fronds that dangled forlornly from its tip. The fire quickly spread through the rest of the smashed thicket — and then the dry grass on the plain beyond began to catch.

A pall of gray-black smoke began to rise up before her. She got to her feet and tried to continue. But, despite the continuing rain, the fire spread quickly. The season had been exceptionally dry, and the savannah was littered with yellowed grass, dried shrubs, fallen trees ripe for burning. Somewhere an elephant trumpeted. Far glimpsed spindly forms fleeing through the murk: giraffes, perhaps.

The hominids were safe, though. The flames would lap harmlessly around their rocky outcrop. Though they would all suffer from the smoke and heat, nobody would die because of this. And if Far could reach the outcrop, she, too, would be safe. But she was still hundreds of meters away, and the screen of smoke and flame cut her off. The flames were leaping hungrily over the long, dry grass, each blade of which burned in an eye blink. The air turned smoky, making her cough. Bits of burning vegetation drifted through the air, blackened, still glowing. When they fell on her skin they stung.

She did the only thing she could do. She turned and ran: ran to the west, away from the fire, away from her family.

She didn’t stop running until she came to a dense thicket of forest. Facing a blank, green wall, she hesitated for one heartbeat. Other dangers lurked here, but this place was surely invulnerable to the fire. She plunged inside.

Crouched close to the root of a tree fern, surrounded by damp clinging fronds, she peered out at the savannah. The fire still swept voraciously through the long grass, and smoke billowed, seeping into the dense forest. But this forest clump was indeed too dense and moist to be under threat. And the fire was quickly consuming its fuel; the rain was starting to douse the flames.

Soon she would be able to get out of here. She squatted down to wait it out.

A scuttling movement close to her foot drew her attention. At the base of the tree fern’s textured root a scorpion moved with metallic precision toward her foot. Without hesitation, but taking care to avoid the sting, she slammed the heel of her hand down on the scorpion. Carefully she picked up the scorpion between two fingers, and lifted it to her mouth.

Something rammed into her back. She was thrown forward onto her belly, with a mass on her back, hot, heavy, muscular. She was surrounded by screeching and hooting, and fists pounded at her back and head.

Winded, summoning up her strength, she rolled over.

A slim figure capered over her. It was not much more than half her height, with a skinny body covered with brown-black fur, long arms, an apelike head stuck over a narrow, conical chest, and a thin pink penis sticking out below its belly. Its fur was wet from the rain, and it stank, the smell musty and strong. And yet it — he — stood upright over her, like one of her own kind, like no ape.

This was a pithecine: an ape-man, a chimp-man, a representative of the first hominids of all, Far’s remote cousin. And there were more of them in the jumbled branches above her, climbing down like shadows.