Aurora - Страница 53

“Look, it’s always been this way,” Freya reminded the executive council when the task force met with the council to discuss it. “There’s no way to sterilize the ship when it’s a set of biomes. It’s alive, that’s all.”

No one could disagree. Howbeit their uneasiness, they simply had to live in a rich broth of bacteria, in a cumulative microgenome that was so much larger than their own genome that it was beyond a complete reckoning, especially as it was fluid and always changing.

But some bacteria were harmful. Same with archaea, fungi, viruses, prions, viris, and v’s. They needed to make distinctions, as part of their ability to keep a healthy biosphere going. Some pathogens had to be tolerated, others had to be killed, if possible; but any attempt to kill bacteria meant that resistant surviving strains of that species would become more dominant and more resistant, in the usual way of things at the micro levels of life, or at all levels of life perhaps.

Dangerous to try to kill things, Freya reminded them. She knew full well, with a sinking sense that she was remembering her earliest memories, that Devi had believed that trying to kill any invasive species usually created more problems than it solved. A destabilized microbiome often caused more harm than anything a balanced microbiome could inflict. Better, therefore, to try to balance things with the least amount of intrusion. Subtle touches, all designed to finesse things for balance. Balance was the crucial thing. Teeter-totters, gently teeter-tottering up and down. Devi had even been an advocate of everyone getting an inoculation of helmiths, meaning ringworms, to give them better resistance to such parasites later. She had been a bit fanatical in that regard, as in so many.

The council and everyone else agreed with Freya on this matter; it was the common wisdom. But they were beginning to suffer problems none of them had seen before. The oldest person aboard was only seventy-eight years old. Median age was thirty-two. None of them had seen all that much in their short lives, and the complex of problems that Aram called zoo devolution was new to them, if not in the abstract, then in the lived experience.

As teams continued to inspect the ship, they found that some of the bacteria living around weld points, and in the gaps and cracks between walls and components, were eating away at the physical substrates of the ship. The corrosion was not chemical but biochemical. As they investigated further they found that all the ship’s walls, windows, framing, gears, and glues had been altered by bacteria, first chemically and then physically and mechanically, in that their function was becoming impaired. Protozoa and amoeba, bacteria and archaea were found on the gaskets around windows and lock doors, also on the components of spacesuits, and in cable insulation, and in the interior panels and chips of the electrical systems, including the computers. Electrical components were often warm, and there was moisture in the air. They were finding microorganisms that lived on and degraded carbon steel, even stainless steel. And anywhere two different kinds of materials met, the microbial life living in the meeting points of these materials created galvanic circuits, which over time corroded both materials. Pitted metal; etched glass; eaten, digested, and excreted plastics: everything had stiffened and disintegrated right in place, without moving except under the forces of the centrifugal rotation of the ship, and the pressure of the ship’s acceleration. Little creatures numbering in the quadrillions or quintillions—it was impossible to get a good estimate, much less a real count—all grew, and ate, and died, and were born and grew again, and ate again. They were eating the ship.

Life is part of the necessary matrix of life, so the ship had to be alive. And so the ship was getting eaten. Which meant that in some respects, the ship was sick.

The weekly meetings of the bacterial task force were similar to the ones Freya had attended as a child, when Devi had plopped her in the corner with some blocks, or paper and pens. Now she sat at the big table, but with about as little to say as when she was a girl. The plant pathologists spoke, the microbiologists spoke, the ecologists spoke. Freya listened and nodded, looking from face to face.

“The organisms in that big water droplet are mostly Geobacter and fungi, but there’s also a prion in there that no one has ever seen on the ship, one that wasn’t there in the beginning.”

“Well, but wait. You mean it wasn’t known about in the beginning. No one saw it. But it had to be there. No way it evolved here from some kind of precursor, not in the time since this ship was built.”

“No? Are you sure?”

The microbiologists discussed this for a while. “Lots of things have had time enough to evolve quite a bit,” one of them said. “I mean that’s our problem, right? The bacteria, the fungi, maybe the archaea, they’re all evolving at faster rates than we are. All organisms evolve at different rates. So discrepancies are growing, because it isn’t a big enough ecosystem for coevolution to be able to bring everything into balance. That’s what Aram has been saying all along.”

Aram was brought into the next meeting to discuss this. “It’s true,” he said. “But I agree that this prion is unlikely to have evolved in the ship. I think it’s just another stowaway, marooned out here with the rest of us. It’s just that now we’ve seen it.”

“And is it poisonous?” Freya asked. “Will it kill us?”

“Well, maybe. Sure. I mean, you don’t want it inside you. That’s the thing about prions.”

“Are you sure it couldn’t have evolved here from some precursor form?”

“I guess it’s possible. Prions are badly folded proteins, basically. And we’ve been exposed to cosmic radiation for a long time now. Possibly some ordinary protein got hit, and wrinkled in a way that turned it into a new kind of prion, in a matrix that allowed it to begin the prion’s weird kind of reproduction. That’s how we think they began on Earth, right?”

“No one is sure,” one of the microbiologists said. “Prions are strange. As far as we can tell from the feeds from Earth, they’re still controversial there too. Still poorly understood.”

“So what do we do about these now?” Freya asked.

“Well, there’s no doubt that these are the kinds of organisms that we might want to try to eradicate. It’s time to break out the pesticides, if we can figure one out. Or decide what the matrix of these prions is, and attack that. Scrub and spray everywhere we think it might be. Fry this water droplet for sure, even toss it into space. It’s a water loss, but we’ll have to take it. One thing that is a little comfort, is that the growth of prions inside mammals is slow. That’s why I don’t think the Auroran pathogen was a prion. When Jochi calls it a fast prion, I think he’s just saying it’s something we don’t recognize. To me it seems more like a really small tardigrade.”

Later Freya went up Spoke Two to visit Jochi, still in his ferry, held magnetically in the space between Spokes Two and Three. He had never wavered in his decision to stick with the ship, and thus with Aram and Freya and Badim, and the ship itself. His anger at the stayers, because of the death of the group in the ferry, was still intense.

He and Freya spoke from positions where they could both look out windows in their respective containers, and see each other face-to-face, separated by two clear plates.

Freya said, “They’ve found a prion in one of the transformer compartments in the spine. Something like Terran prions.”

Jochi nodded. “I heard about that. Do they think it came from me?”

“No. It’s very like Terran prions. Like one of the ones that cause mad cow disease.”

“Ah. Slow-acting.”

“Yes. And it isn’t clear it’s gotten into anything but a water droplet in an electrical compartment.”

Jochi shook his head. “I don’t understand how that could be.”

“Neither does Aram. None of them understand it.”

“Prions, wow. Are people scared?”

“Yes. Of course.”

“Of course.” His expression grew grim.

“So.” She put her hand on her window. “How are you doing out here?”

“I’m all right. I’ve been watching a fascinating feed from China. They seem to have made some great progress in epigenetics and proteomics.”

“What else, though? Have you done any stargazing?”

“Oh yes. A couple of hours every day. I’ve been looking in the Coal Sack. And finding new ways to look through our magnetic screen toward Sol. Although it could be the screen is distorting the image. Either that, or else Sol is pulsing a little. I sometimes think it’s signaling us.”

“Sol? The star?”

“Yes. It looks like that.”

Freya looked at him silently.

Jochi said, “And I’ve seen the five ghosts again too. They’re getting pretty upset for some reason. The Outsider seems to think we’re in trouble. Vuk just laughs at him.”

“Oh Jochi.”

“I know. But, you know. They have to talk to someone.”

Freya laughed. “I guess they do.”

So as they flew back toward Sol, they tried to settle into their new lives, which were like their old lives, and yet somehow not. There were fewer of them, for one thing, and all in Ring B. And after the trauma of the schism, and choosing to head back to the solar system and its gigantic civilization, there were many in the ship who wanted to find new ways of doing things. Less regulation of their lives, less governance; less anxious studying of all that they needed to know to run the ship.