Seveneves - Страница 116

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A canid was a thing like a dog, wolf, or coyote. Rather than trying to bring back individual species, Doc — Dr. Hu Noah — had drawn inspiration from research that had emerged in Old Earth scientific journals shortly before Zero, suggesting that the boundaries among those commonly recognized species were so muddy as to be meaningless. They all could and did mate with each other and produce hybrid offspring. For various reasons these tended to group by size and shape in a way that human observers saw as being distinct species. But when humans weren’t looking, or when the environment shifted, all manner of coy-dogs and coy-wolves and wolf-dogs appeared. Coyotes began hunting in packs like wolves, or wolves went solo like coyotes. Creatures that had avoided, or eaten, humans struck up partnerships with them; family pets went feral.

Hu Noah was 120 years old. As a young man he had been one of many scientists who had rebelled against a tradition of TerReForm thought that had passed as gospel for hundreds of years previously. Thanks in part to the young Turks’ propagandizing, this older approach had become hidebound and stereotyped as the TOT, or Take Our Time, school. The premise of TOT was that ecosystems — which on Old Earth had evolved over hundreds of millions of years — would have to be rebuilt slowly, through a sort of handcrafting process. Which was fine, since living in habitats was safer and more comfortable anyway than the unpredictable surface of a planet. The human races could enjoy thousands of years of safe, secure habitat life while slowly re-creating ecosystems down below that would resemble those of Old Earth. The planet would become a sort of ecological preserve. Africa, whose outlines were still vaguely recognizable, though heavily reshaped by the Hard Rain, would have giraffes and lions sequenced from the ones and zeroes dating all the way back to the thumb drive around Eve Moira’s neck. Likewise with the other battered and reforged continents.

Doc was the last surviving member of the young Turk faction that had named, then rubbished, “the TOT lot.” They were called the GID, or Get It Done, school. Their leader had been Leuk Markov, who himself had been over a hundred years old when he had become Doc’s teacher. Obviously from his name (which was taken from the surname of Eve Dinah’s boyfriend Markus), Leuk had been a Dinan, but Doc and most of his followers were Ivyns, which gave them an air of seriousness and credibility that had proved useful in pressing their agenda. They had formed a partnership with mostly Moiran philosophers who had begun questioning the TOT lot’s premises, pointing out that re-creating simulacra of Old Earth biomes, in addition to taking an unreasonably long time, reflected a basically sentimental way of thinking about nature. It was an expression of a sort of post-traumatic stress disorder that the human races had carried on their backs ever since the Hard Rain. It was time to discard that. The old ecosystems would never return. Even if it were possible to bring them back, it would take so long as to not be worth it. In any event — and this was the nail in the coffin, supplied personally by Doc — it would fail anyway because the forces of natural selection were unpredictable and uncontrollable.

The most powerful weapon in the GID school’s arsenal, however, was not philosophy. It was impatience, a failing shared to a greater or lesser degree by all the races. Second only to that was competitiveness, a quality absent in Camites but present in the other six. Anyone so motivated would of course want to Get It Done, to make the TerReForm happen in centuries rather than millennia.

Their rise to power had, however, produced political consequences they had never imagined by giving the races something to compete for — namely, territory on the surface of New Earth.

In the early 4820s, Leuk Markov had published papers speculating that the surface of New Earth could be made ready for permanent human habitations as early as 5050. While that was startlingly soon by the standards of the Take Our Time school, it had seemed far in the future to the average person, and so the council of scientists responsible for planning the TerReForm had seen no problem with enshrining it in the schedule, and later even moving it up to 5005—the anniversary of the landing on Cleft. But the shift in thinking had unleashed long-pent-up political forces that had led to the formation of what amounted to two different countries in the year 4830. The Aïdans, who dominated one of them, bringing many Camites and Julians under their sway, had built the turnpikes at Kiribati and Dhaka in 4855, cleaving the ring. They eventually came up with a formal name for their country, obliging the rest of the ring to come up with a name for theirs, but everyone simply called them Red and Blue.

TerReForm had continued anyway, through ad hoc cooperation between scientists and labs straddling the Red/Blue borders. Twenty-three years later, however — practically as soon as New Earth’s atmosphere had become breathable without artificial aids — had begun the War on the Rocks, a struggle carried out partly in space but mostly on the still-nude surface of New Earth. This had been terminated in 4895 by what was now called First Treaty, which stipulated among other things how subsequent TerReForm activity was going to proceed. It had thus paved the way for the Great Seeding, which was responsible for the trees that Kath Two had been flying over this morning. In subsequent decades, larger and larger animals had been set loose on the surface as part of a planned program to jump-start whole ecosystems.

Some of those — the ones Kath Two had been worried about this morning — were canids. When Rhys said that they were “going epi,” he meant that they were passing through some kind of epigenetic shift.

If the Agent had blown up the moon a couple of decades earlier, Eve Moira wouldn’t have known about epigenetics. It was still a new science at the time she was sent up to the Cloud Ark. During her first years in space, when she and her equipment had been coddled in the most protected zones of Izzy and Endurance, she’d had plenty of time to bone up on the topic. Like most children of her era, she’d been taught to believe that the genome — the sequence of base pairs expressed in the chromosomes in every nucleus of the body — said everything there was to say about the genetic destiny of an organism. A small minority of those DNA sequences had clearly defined functions. The remainder seemed to do nothing, and so were dismissed as “junk DNA.” But that picture had changed during the first part of the twenty-first century, as more sophisticated analysis had revealed that much of that so-called junk actually performed important roles in the functioning of cells by regulating the expression of genes. Even simple organisms, it turned out, possessed many genes that were suppressed, or silenced altogether, by such mechanisms. The central promise of genomics — that by knowing an organism’s genome, scientists could know the organism — had fallen far short as it had become obvious that the phenotype (the actual creature that met the biologist’s eye, with all of its observable traits and behaviors) was a function not only of its genotype (its DNA sequences) but also of countless nanodecisions being made from moment to moment within the organism’s cells by the regulatory mechanisms that determined which genes to express and which to silence. Those regulatory mechanisms were of several types, and many were unfathomably complex.

Had it not been for the sudden intervention of the Agent, the biologists of Old Earth would have devoted at least the remaining decades of the century to cataloging these mechanisms and understanding their effects — a then-new science called epigenetics. Instead of which, on Cleft, in the hands of Eve Moira and the generations of biologists she reared, it became a tool. They had needed all the tools they could get, and they had wielded them pragmatically, bordering on ruthlessly, to ensure the survival of the human races. When creating the children of the other six Eves, Moira had avoided using epigenetic techniques. She had felt at liberty, however, to perform some experiments on her own genome. It had gone poorly at first, and her first eight pregnancies had been failures. But her last, the only daughter of Moira to survive, had flourished. Cantabrigia, as Moira had named her after the university of Cambridge, had founded the race of which Kath Two was a member.

By the time the Great Seeding was in the works, thousands of years later, epigenetics was sufficiently well understood to be programmed into the DNA of some of the newly created species that would be let loose on the surface of New Earth. And one of the planks in the Get It Done platform was to use epigenetics for all it was worth. So rather than trying to sequence and breed a new subspecies of coyote that was optimized for, and that would breed true in, a particular environment, as the TOT school would have had it, the GID approach was to produce a race of canines that would, over the course of only a few generations, become coyotes or wolves or dogs — or something that didn’t fit into any of those categories — depending on what happened to work best. They would all start with a similar genetic code, but different parts of it would end up being expressed or suppressed depending on circumstances.

And no particular effort would be made by humans to choose and plan those outcomes. They would seed New Earth and see what happened. If an ecosystem failed to “take” in a particular area, they would just try something else.

In the decades since such species had been seeded onto New Earth, this had been going on all the time. Epigenetic transformation had been rampant — and, since Survey was thin on the ground, largely unobserved by humans. Still, when it led to results that humans saw, and happened to find surprising, it was known as “going epi.” Use of the phrase was discouraged for being unscientific, but Rhys Alaskov knew how to get away with it.

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