There was no design in this: no sense of improvement, of purpose. All that was happening was that each organism was struggling to preserve itself, its offspring, and its kin. But as the environment slowly changed, so through relentless selection did the species that inhabited it. It was not a process fueled by life, but by death: the elimination of the less well adapted, the endless culling of inappropriate possibilities. But the potential of an unseen future was no consolation to those who lived through the relentless culling.
Many of the adapids had become too specialized. This comfortable planet-swaddling warmth would not last forever. In cooler times in the future, as the forests became sparse and seasonal differences became more pronounced, it wouldn’t seem so smart to be a fussy eater. Extinctions would follow, as they always had.
Meanwhile, amid this clutter of exotic primates, the siblings found no notharctus.
Exploring the forest floor, Noth found a plant with podded fruit, a kind of pea. He broke open a few pods and let his sister feed.
A kind of anteater, a meter long, approached a pillarlike ants’ nest. It fell on the nest, wielding its powerful arm and shoulder muscles. As though it wielded a pickaxe, all its force was concentrated on a single point, the tip of its strongly flexed middle finger. The ants swarmed — they were huge, each some ten centimeters long — and the anteater quickly ingested them with its long, sticky tongue before the soldiers could unite in defense. The anteater was a descendant of South American stock, which had wandered here over temporary land bridges many generations before.
Noth and Right watched, wide-eyed. But as he kept an eye on the anteater, concern gnawed at Noth’s unconscious.
He had tried to keep them both feeding, to fatten up their tails with the winter storage that would see them through the long months of hibernation to come. That was just as his innate programming instructed. But they weren’t eating enough. Isolated from the support of the troop, he was having to spend much too much of his time watching for predators.
He could have gone back. Like all his species — the mobile males more than the sedentary females — he kept track of his position by dead reckoning, integrating time, space, and the angle of the slanting sunlight. It was an ability that helped him find scattered sources of food and water. If he needed to Noth could find his way back “home,” to the stand of trees that had been the center of his troop’s range. But he never heard the distinctive warbling song of his troop; his rudimentary decision-making machinery pressed him to keep searching for a troop that would accept him and his sister.
Meanwhile, though the sun still circled endlessly above the horizon, much of the daylight was tinged with the red of sunset, and here on the forest floor brown spores clung to the fern fronds. Autumn was coming. And then there would be winter. They were underfed, and time was running out.
Right became distressed, as she so often did. She dropped the pea pods and folded over on herself, rocking, keening softly, her hands over her small face. Noth took her in his arms and carried her to the crook of a branch, where he began to groom her. He worked carefully through the sparse fur on her back, neck, head, and belly, removing dirt, bits of leaf, and dried feces, untangling knots, picking out parasites that were attempting to feast on her young skin.
Right quickly calmed. The grooming’s mixture of pleasure, attention, and mild pain flooded her system with endorphins, her body’s natural opiates. Before she grew much older she would be addicted, literally, to this pleasurable scratching — as her brother already was. Noth badly missed the strong, nipping caress of adult fingers on his back.
But Noth was worried about her, on deep levels he could not understand.
Right’s bewildering grief served a purpose. It was a signal to her that she had suffered a loss, that there was a hole in her world that she must fix. And though Noth was not capable of true empathy — if you didn’t really understand that other people had minds and thoughts and feelings like yours, you couldn’t possibly be empathetic — still the signs of grief in his sister triggered a kind of protectiveness in him. He wanted to put the world right for his sister: The instinct to help the orphaned went very deep.
But in the end obsessive grief was maladaptive. If Right was unable to recover, in the end there would be nothing he could do for her. He would have to abandon her, and then she would surely die.
As day followed day, the sun, at the lowest point of its arc in the sky, began to slip beneath the southern horizon. At first the brief nights were like twilight, and on clear nights purple-red curtains of light climbed into the tall sky. But quickly the sun’s excursions into invisibility became longer, and there were increasing intervals when stars shone in a deepening blue. Soon true darkness would return to the polar forest.
The weather quickly became colder and drier. Rainfall was scarce now, and on some days the warmth of the sun barely seemed to penetrate the lingering mist. Already many of the birds of the forest canopy had departed, skein after skein of them flitting over the sky to the warmer lands to the south, watched by uncomprehending primate eyes.
Noth became exhausted, ragged, and his dreams were full of flashing teeth and biting claws, visions of his scrap of a sister taken by gigantic mouths.
Now their biggest problem was thirst. It had been so long since the last rain that the treetops were becoming parched. And already the trees were starting to shed; the last leaves were withered and brown. Soon Noth was reduced to licking the bark each morning for the cold dew.
At length, driven by their thirst, the siblings went in search of ground water. Near the closest large lake they scurried down a tree trunk, eyes wide.
Approaching the water, the primates crept past a pair of what looked like miniature deer. The size of small dogs with long, trailing tails, these fast, solitary runners, browsing on leaves and fallen fruit, were ancestors of the mighty artiodactyl family, which would one day include pigs, sheep, cattle, reindeer, antelope, giraffes, and camels. Right disturbed a frog, which hopped away, croaking in protest. She cowered back, eyes wide at its strangeness. Soon they saw more amphibians, frogs and toads and salamanders. Birds crowded the bushes, raising shrill cries that filled the dank air.
Noth was uneasy. The shore was too crowded: Noth and Right were not the only thirsty creatures in this shivering jungle.
A meter-long creature like a long-tailed kangaroo ran past; this was a leptictidium, a hunter of small animals and insects. Exploring the ground with its mobile nose, it disturbed a pholidocercus, a spiky-haired ancestor of the hedgehogs, that indignantly hopped away like a rabbit. Here was a close-packed herd of horses. They were tiny: no larger than terriers, with perfectly formed equine heads. Shyly these exquisite little creatures picked their way through the undergrowth. They walked on pads, like cats, and on each foot they had several hoofed toes. Their genus had emerged in Africa only a few million years earlier. A rough growl from an impatient carnivore startled the little horses, making them stir into sudden flight.
Through this exotic crowd the two primates proceeded cautiously, moving in scurries, in fits and starts.
The water itself was a languid sheet, dense with matted vegetation, dead reeds, and algal blooms. In places ice had already formed in thin gray slices. But on the open water birds waded, ancestors of flamingos and avocets, and huge water lilies rested languidly on the surface.
Over the open water a spider was suspended on a thread of silk, and huge ants flew, each as large as a human hand, on their way to found new nests. Through this crowd of insects flapped a family of delicate bats. Recently evolved, as huge and fragile as paper kites, the new flying mammals snapped at the insects. Primitive bony fish broke the surface and gulped at the aerial fodder, as did a twisting eel.