Evolution (88 page)

Where continents met, new mountain ranges were stitched. Where the Mediterranean had been there was now a mighty mountain range that reached eastward toward the Himalayas. It was the final extinction of the ancient Tethys. No trace of Rome had survived: the bones of emperors and philosophers alike had been crushed, melted, and gone swimming into the Earth itself. But while mountains were built, others evaporated like dew. The Himalayas were eroded to stumps, opening up new migration routes between India and Asia.

Nothing mankind had done in its short and bloody history had made the slightest bit of difference to this patient geographical realignment.

Meanwhile the Earth, left to its own devices, had deployed a variety of healing mechanisms, physical, chemical, biological, and geological, to recover from the devastating interventions of its human inhabitants. Air pollutants had been broken up by sunlight and dispersed. Bog ore had absorbed much metallic waste. Vegetation had recolonized abandoned landscapes, roots breaking up concrete and asphalt, overgrowing ditches and canals. Erosion by wind and water had caused the final collapse of the last structures, washing it all into sand.

Meanwhile the relentless processes of variation and selection had worked to fill an emptied world.

The sun climbed higher. Despite all that had happened to Remembrance, it was not yet midday.

She was stranded on a grassy plain, with purple volcanic hills in the distance, a few sparse stands of trees and shrubs, and a brown patch of borametz, the new kind of tree. Here, in the rain shadow of those purple hills, the rainfall was intermittent and erratic. The soil was habitually dry, and in such conditions trees were unable to establish themselves, and the grasses continued their ancient dominion— almost. Even vegetable communities evolved. And now the grasses had new competitors, in the borametz groves.

The tree that had saved her from the fall was barren of fruit, parched, clinging to life in the dry soil of this grassland. There was nothing to eat here— nothing but the scorpions and beetles that squirmed from beneath the rocks, bugs she popped into her mouth.

She made out a belt of forest, huddled against those remote purple hills, shimmering in the heat haze. Vaguely she realized that if she could get there she would be safer, she might find food, even people of her own kind.

But the forest was far away. Remembrance’s distant grandmothers would have easily walked across this stretch of open savannah. But not Remembrance. She was too clumsy a walker. And like Capo, a chimplike ape of a different time, her kind had regrown their hair and forgotten how to sweat.

So she sat there, her mind empty of plans, waiting for something to turn up.

Suddenly a slim head swooped down from the washed-out sky. Remembrance chattered and flinched back against the tree trunk. She saw black round eyes, wide with surprise, set in a slender, fur-covered face, and two long ears that swept back against an elegant neck. It was a rabbit’s head— but it was large, as large as a gazelle’s.

The rabbit-gazelle evidently decided that the cowering hominid was no particular threat to her. She proceeded to crop at the grass that grew thinly in the shade of the tree.

Cautiously Remembrance crept forward.

Her visitor was one of a herd, she saw now, scattered over the plain and grazing patiently on the grass. They were tall, some twice as tall as she was. Slim, graceful, they looked like gazelles— but they were indeed descended from rabbits, as their long ears and small white tails clearly demonstrated.

The legs of these animals were like gazelles’, too. Their forelegs were straight, and could be locked into position to support the animal with little effort. But halfway down their hind legs these rabbits had backward-bending joints that were in fact ankles. The lower leg was like an extended foot— balanced on two hooflike toes— and the knee was up near the torso, hidden in fur. Their back legs held in a permanent sprinter’s crouch, the rabbit-gazelles were constantly ready for flight, the most critical task in their lives. As they grazed, the youngest scuttling at the feet of their elders, the herd remained compact, and there was never a time when at least one of the adults was not scanning the grass.

The reason for all of this soon became apparent. One of the bigger bucks startled, went rigid, fled. The rest of the herd followed immediately, in a blur of speed and dust.

From the cover of a bluff of rocks a slim black form darted forward. It was another rat, this one shaped to run with the low-slung power of a cheetah. The rat-cheetah disappeared into the dust, pursuing the rabbit herd.

Stillness resumed. For a time, nothing moved over the grass-covered plain, nothing but the shimmer of the air. The sun slid away from its height. But the heat did not lessen, and thirst clawed at Remembrance’s throat.

She crept out of her hiding place. Her very human face, with straight nose, small mouth and chin, wrinkled in the bright afternoon light. She raised herself to her full height and sniffed. She heard a lowing, a clattering of tusks that sounded as if it were coming from the east, away from the sun. And she smelled the tang of water.

She began to run that way. She moved in scurries, hurrying from one patch of covering shade to the next, with frequent drops to an all-fours lope. This daughter of mankind ran like a chimp.

At last she crested a shallow bluff of eroded sandstone. She found herself facing a broad lake. It was fed by streams that snaked from more distant hills, but she could see that it was choked with reeds and fringed by a broad mud pan. She found an acacia to shelter under, and peered out, trying to find a way to get to the water.

Here, just as they always had, the herbivores had gathered to drink.

She saw more rabbits. There were skittish gazellelike creatures of the kind she had seen before. But there were also heavier-built, bisonlike powerhouses— and, running around their feet, smaller creatures that hopped and jumped. The rabbits, widespread and fast breeding, had, after the fall of man, radiated and adapted quickly. But not all of the new species had abandoned the ancient ways. There were still smaller browsers, especially in the forests where small beasts kicked and leapt and hopped as their ancestors always had.

Meanwhile warthogs snuffled and snorted in the muddy fringe of the lake, left all but unchanged by time. If there was no need to adapt, nature was conservative. And Remembrance made out huge, slow-moving creatures, marching serenely through the shallow water. They were related to the goats she had encountered in the forest, but these were giants, with tree trunk legs and horns that curled like mammoth tusks. They lacked trunks— none of these ruminants had evolved that particular anatomical trick— but, giraffelike, they had long necks that let them reach the succulent leaves growing on low-hanging tree branches, or the water of the lake.

A herd of different goat descendants stood knee-deep in the water. They had webbed feet that kept them from sinking in soft mud and sand. Each had a broad bill-like mask before its face. Sculpted from horns, these bills were used for browsing on the soft weeds found at the edge of the lakes. Sucking peacefully at the lakeside vegetation, these goats were like nothing so much as the hadrosaurs, the long-vanished duck-billed dinosaurs.

And, just as the hadrosaurs had been the most diverse group of dinosaurs before the comet fell, so this rediscovery of an ancient strategy was enabling a new radiation. Already many species of the duck-billed goats, subtly distinguished by differences in horn design, size, and diet preferences, were to be found at many of the water courses of the world’s tropical regions and elsewhere.

Meanwhile, all around this scene of relatively peaceful herbivorous thirst-quenching— just as there had always been— intent predatory eyes watched the herbivores at work.

Watching this scene with half-closed eyes it would not have been impossible to imagine that the animals obliterated by human action had been restored. But on this new African savannah the familiar roles had been taken up by new actors, descended from creatures that had best survived the human extinction event. These were those that had resisted all of mankind’s attempts at extirpation: the vermin, especially the generalists— starlings, finches, rabbits, squirrels— and rodents like rats and mice. Thus there were rabbits morphed into gazelles, rats become cheetahs. Only subtleties were changed— a nervous twitchiness about the rabbits, a hard-running intensity about the rats that had replaced the cats’ languid grace.

There was a sudden flurry of activity, a great clash like a bone breaking. Two of the great goat-elephants, males, had begun a dispute. Their heads bobbed and swayed atop long giraffelike necks, and their horns, elaborately curling before their faces, clashed like baroque swords.

Remembrance cowered deep into the shade of her acacia. As the great herbivores began to mill around her, disturbed by the battle, she wasn’t so safe. This tree, trunk and all, could be smashed up and devoured in a few heartbeats.

And now the watchful predators took advantage of the confusion.

A pack of them erupted from cover. Lean and vulpine, with long, powerful shanks and thickly padded feet, they were more rats. Working closely together, they moved wedgelike to separate one older goat-elephant from the rest of the herd. His huge horn-tusks chipped and scarred by a lifetime of battles, this big male bellowed his rage and fear and began to run. The rats settled into the pursuit, running closely together.

These rat derivatives were like dogs, yet they were not dogs. Their characteristic rodents’ incisors had been subtly modified from teeth designed for processing seeds and insects into blades with stabbing points. Their rear molars were like shears, well equipped for shredding meat. And they moved more closely than any dog pack had ever run, with a liquid, slithering power. But, like a dog pack, their basic strategy was to chase the goat-elephant until he was exhausted.

Soon the prey and his pursuers had passed out of sight.

The goat-elephants settled down once more to their drinking and fighting— though some of them turned their great heads to the place where the old one had stood, remembering his absence.

Remembrance took the opportunity to creep forward.

The water was scum laden. But she scooped it up in her hands and let it trickle into her mouth, leaving her palms and fingers coated with fine green slime.

From the water, two yellow eyes watched her with abstract instinct. It was a crocodile, of course. These ancient survivors had ridden out the human apocalypse as they had survived so many before: by living off the gruesome brown food chain of the dying lands, by burrowing into the welcoming mud in drought. And even now no animal, no pig or rabbit or primate, no fish or bird, reptile or amphibian— not even the rodents— had managed to dislodge the crocodiles from their watery kingdom.

Remembrance shuddered, and backed off from the water’s edge.

A new predator stalked over the bluff toward the lake. Again Remembrance scurried for cover, screened by the huge, impassive bodies of a herd of duck-billed goats.

This predator was more rodent stock; in fact it came from a kind of mouse. But its behavior was not like any dog or cat’s. It came to the edge of the water, and lifted itself up on its massive hind legs. The herbivores at the water’s edge cowered away. But the mouse-raptor had no interest in the creatures milling before it. With lordly dismissal it dipped its ferocious muzzle to taste the water. Then it stalked back to dry land where it used its small, feeble-looking hands to pluck at the grass, as if testing it.

It looked like one of the great carnivorous dinosaurs of the Cretaceous days. Its forearms were small, its tail was thickened for balance, and its hind legs were awesomely powerful machines of muscle and bone. Its incisors had developed into ferocious slashing weapons, to be deployed by thrusts of the heavy head. The mouse-raptor was a land shark, like a tyrannosaur, a body design rediscovered and made devastatingly effective. And yet this arrogant creature retained the small ears and brown fur of the diminutive rodents from which it had derived.

The mouse-raptor seemed satisfied with the water and the grass. It squealed, spat, and drummed its tail on the ground. From the distance there was a series of answering calls, drums, and cries.

More mouse-raptors approached the lake. They fanned out over a swath of grassland, sniffing the air. A few kits ran around the legs of the adults, wrestling and nipping at each other with the ancient playful curiosity of predators.

When they had gathered, the adult mouse-raptors turned, opened their throats, and set up a kind of synchronized wailing. In response, a herd of another kind of animal came lumbering toward the water.

These were big creatures, as big as the goat-elephants. Nervously they huddled together, querulously jostling. But even as they stumbled toward the water, under the apparent guidance of the mouse-raptors, they cropped hastily at the grass under their feet.

Their bodies were coated with sparse fur. Their heads were crested, their skulls shaped to allow anchorage for the tremendous cheek muscles that worked their immense lower jaws: Their heads looked rather like those of robust pithecines, in fact. Their ears, plastered back over their massive skulls, were huge and veined, great radiator fins designed to extract waste heat from their huge bodies. Though their hind legs were massive, enabling them to support their weight, they had the peculiar wrong-way-bending look of the rabbit-gazelles: legs meant for fleeing.

These animals were ugly, elephantine. But they had not descended from goat or pig. They had forward-looking eyes under heavy browridges, huge dark eyes that peered at the world, baffled and fearful. They walked on all fours, but they supported themselves on the folded knuckles of their hands, a posture that had once been called knuckle-walking.

Like Remembrance, their ancestors had once been human.

Remembrance waited until the big dull animals had settled to their drinking, jostling querulously, their ears spreading in the cooling air of the afternoon. Then she crept away.