Year's Best Scifi 2 Part 31

And then I noticed Rimb, melding all by herself in a corner, and she looked so cute doing it that I went over to join her.

Joan Slonczewski

Joan Slonczewski is a scientist and writer who lives in Gambier, Ohio, and teaches at Kenyon college.

Her novels, such as her famous A Door into Ocean, are informed by Quaker ideals and feminism, as well as by the loving scientific details underpinning the story. This is a rare short story by one of the finest younger SF writers. It is set in the same future universe as the novel mentioned and its sequel, Daughter of Elysium, but in a different place and in the distant future of even that imagined setting. Like the Baxterstory, it harks back to the fiction of Hal Clement and, in this case, James Blish of "Surface Tension,"

inventing and solving a clever SF problem posed by a precisely imagined world of wonders. It appeared in a.n.a.log.

Microbe

by Joan Slonczewski

"That rat didn't die." Andra walked around the holostage. Before her, projected down from the geodesic dome, the planet's image shone: Iota Pavonis Three, the first new world approved for settlement in over four centuries. As Andra walked around, the swirl of a mysterious continent peered out through a swathe of cloud. She stopped, leaning forward on her elbows to watch. What name of its own would the Free Fold Federation ultimately bestow on IP3, Andra wondered; such a lovely, terrifying world.

"Not the last time, the rat didn't." The eye speaker was perched on her shoulder. It belonged to Skyhook, the sentient shuttle craft that would soon carry Andra from the study station down to land on the new world. A reasonable arrangement: The shuttle craft would carry the human xen.o.biologist through s.p.a.ce for her field work, then she would carry his eye on the planet surface, as she did inside the station.

"The rat only died down there the first eight times."

"Until we got its 'skin' right." The "skin" was a suit of nanoplast, containing billions of microscopic computers, designed to filter out all the local toxins-a.r.s.enic, lanthanides, bizarre pseudoalkaloids. All were found in local flora and fauna; inhaling them would kill a human within hours. In the old days, planets had been terraformed for human life, like Andra's own home world Valedon. Today they would call that ecocide. Instead, millions of humans would be lifeshaped to live here on planet IP3, farming and building-the thought of it made her blood race.

"We got the right skin for the rat," Skyhook's eye speaker pointed out. "But you're not exactly a rat."

From across the holostage, an amorphous blob of nanoplast raised a pseudopod. "Not exactly a rat,"

came a voice from the nanoplast. It was the voice of Pelt, the skinsuit that would protect Andra on the alien planet surface. "Not exactly a rat-just about nine-tenths, I'd say. Your cell physiology is practically the same as a rat; why, you could even take organ grafts. Only a few developmental genes make the difference."

Andra smiled. "Thank the Spirit for a few genes. Life would be so much less interesting."

Pelt's pseudopod wiggled. "The rat lived, and so will you. But our nanoservos completely jammed." The microscopic nanoservos had swarmed into sample life forms from IP3 to test their chemical structure. But for some reason they could barely begin to send back data before they broke down. "n.o.body cares about them."

"Of course we care," Andra said quickly. Pelt never let anyone value human life above that of sentient machines. "That's why we cut short the a.n.a.lysis, until we can bring samples back to the station. That's why we're sending me."

"Us," he corrected.

"All right, enough already," said Skyhook. "Why don't we review our data one last time?" "Very well." A third sentient voice boomed out of the hexagonal panel in the dome directly overhead. It was the explorer station herself, Quantum. Quantum was considered female, the others male; Andra could never tell why, although sentients would laugh at any human who could not tell the difference. "Here are some microbial cells extracted from the soil by the last probe," said Quantum.

The planet's image dissolved. In its place appeared the highly magnified shapes of the microbes. The cells were round and somewhat flattened, rather like red blood cells. But if one looked closer, one could see that each flattened cell was actually pinched in straight through like a bagel.

"The toroid cell shape has never been observed on other planets," said Quantum. "Otherwise, the cell's structure is simple. No nuclear membranes surround the chromosomes; so, these cells are like bacteria, prokaryotes."

Skyhook said, "The chromosome might be circular, too, as in bacteria."

"Who knows?" said Pelt. "On Urulan, all the chromosomes are branched. It took us decades to do genetics there."

"We just don't know yet," said Quantum. "All we know is, the cells contain DNA."

"The usual double helix?" asked Skyhook. The double helix is a ladder of DNA nucleotide pairs, always adenine with thymine or guanine with cytosine, for the four different "letters" of the DNA code. When a cell divides to make two cells, the entire helix unzips, then fills in a complementary strand for each daughter cell.

"The nanoservos failed before they could tell for sure. But it does have all four nucleotides."

Andra watched the magnified microbes as their images grew, their ring shapes filling out like bagel dough rising. "I'll bet their chromosomes run right around the hole."

At her shoulder Skyhook's eye speaker laughed. "That would be a neat trick."

Quantum added, "We identified fifteen amino acids in its proteins, including the usual six." All living things have evolved to use six amino acids in common, the ones that form during the birth of planets. "But three of the others are toxic-"

"Look," exclaimed Andra. "The cell is starting to divide." One of the bulging toroids had begun to pucker in, all along its circ.u.mference. The puckered line deepened into a furrow all the way around the cell.

Along the inside of the "hole," a second furrow deepened, eventually to meet the furrow from the outer rim.

"So that's how the cell divides," said Skyhook. "Not by pinching in across the hole; instead it slices through."

"The better to toast it."

At that Pelt's pseudopod made a rude gesture. "Pinching the hole in wouldn't make sense, if your chromosome encircles the hole; you'd pinch off half of it."

Andra squinted and leaned forward on her elbows. "I say-that cell has three division furrows."

"The daughter cells are dividing again already?" Skyhook suggested.

"No, it's a third furrow in the same generation. All three furrows are meeting up in the middle.""That's right," boomed Quantum's voice. "These cells divide in three, not two," she explained. "Three daughter cells in each generation."

Sure enough, the three daughter cells appeared, filling themselves out as they separated. Other cells too had puckered in by now, at various stages of division, and all made their daughters in triplets. "How would they divide their chromosomes to make three?" Andra wondered. "They must copy each DNA helix twice before dividing. Why would that have evolved?"

"Never mind the DNA," said Pelt. "It's those toxic amino acids you should worry about."

"Not with you protecting me. The rat survived."

Quantum said, "We've discussed every relevant point. We've established, based on all available data, that Andra's chance of survival approaches one hundred percent."

"Uncertainties remain," Skyhook cautioned.

Andra stood back and spread her hands. "Of course we need more data-that's why we're going down."

"All right," said Skyhook. "Let's go."

"I'm ready." Pelt's pseudopod dissolved, and the nanoplast formed a perfect hemisphere.

Andra unhooked Skyhook's eye speaker from her shoulder. Then she walked back around the holostage to lift the hemisphere of Pelt onto her head. Pelt's nanoplast began to melt slowly down over her black curls, leaving a thin transparent film of nanoprocessors covering her hair, her dark skin, and her black eyes. It formed a special breather over her nose and mouth. Everywhere the nanoplast would filter the air that reached her skin, keeping planetary dust out while letting oxygen through. The film covered the necklace of pink andradites around her neck, spreading down her s.h.i.+rt and trousers. She lifted each foot in turn to allow the complete enclosure. Now she would be safe from any chemical hazard she might encounter.

In Skyhook's viewport, the surface of planet IP3 expanded and rose to meet them. Numerous tests had established its physical parameters as habitable-gravity of nine-tenths g, temperatures not too extreme, oxygen sufficient and carbon dioxide low enough, water plentiful. The ozone layer could have been denser, but human colonists would have their eyes and skin lifeshaped for extra enzymes to keep their retina and chromosomes repaired.

At a distance the planet did not look remarkably different from Andra's home world. A brilliant expanse of ocean met a mottled brown sh.o.r.e, rotating slowly down beneath the craft. Beyond, in the upper lat.i.tudes, rolled the blue-brown interior of a continent, broken only by a circle of mountains.

As Skyhook fell swiftly toward the land, curious patterns emerged. Long dark bands ran in parallel, in gently winding rows like a string picture. The lines were bands of blue vegetation; the probe had sent back footage of it, wide arching structures tall as trees. Each band alternated with a band of yellow, which gave way to the next band of blue. Over and over the same pattern repeated, ceasing only at the mountains.

"I've never seen patterns like that on uncolonized worlds," Andra mused.

"They do look like garden rows," Skyhook admitted. "Perhaps the native farmers will come out to greet us."If there were intelligent life forms, they had yet to invent radio. A year of monitoring the planet at every conceivable frequency had yielded nothing, not so much as a calculation of pi.

Skyhook landed gently in a field of dense vegetation. The wall of the cabin opened, the door pulling out into an arch of nanoplast. A shaft of brilliant light entered.

"All systems check," crackled Quantum's voice on the radio in her ear. "Go ahead."

Andra gathered her field equipment and set Skyhook's eye upon her shoulder again. Then she stepped outside.

The field was a riot of golden ringlets, like wedding bands strewn out. Her gaze followed the cascade of gold down to the edge of the field, where taller dark trunks arose in shallow curves, arching overhead.

From the taller growth came a keening sound, perhaps some living thing singing, or perhaps the wind vibrating somehow through its foliage. "It's beautiful," she exclaimed at last.

Beneath the golden ringlets grew dense blue-brown vegetation, reaching to Andra's waist. She bent closer for a look. "These look like plants, 'phycoids.' The ringlets might be flowers."

"They could just as well be snakes ready to snap," warned Skyhook. "Watch your step."

She looked back at the shuttlecraft, planted in the field like a four-legged insect. Then she lifted her leg through the foliage, Pelt's nanoplastic "skin" flexing easily. Immediately her foot snagged. She tried to pull out some of the growth, but found it surprisingly tough and had to cut it with a knife. "The leaves and stems are all looped," she observed in surprise. All looped, just like the 'flowers.' I'll never get through this stuff."

Pelt said, "They are phycoid. I detect products of photosynthesis."

"They could be carnivorous plants," Skyhook insisted.

Andra collected some more cuttings into her backpack. "I wish I could smell them," she said wistfully.

Pelt's skin filtered out all volatile organics. She aimed her laser pen to dig one out by the roots. The phycoid came up, but nearby stems sparked and smoldered.

"Watch out!" squeaked the eye speaker.

She winced. "Don't deafen me; I'll put it out." She stamped the spot with her boots and sprinkled some water from her drinking jet. "This planet's a fire trap." The phycoid roots, she noted, were long twisted loops, tightly pressed together, but loops nonetheless. All the living structures seemed to be bagels squashed and stretched.

"Great Spirit, we've got company," Skyhook exclaimed.

Andra looked up. She blinked her eyes. A herd of brown-striped truck tires were rolling slowly across the field. To get a closer look, she pressed through the phycoids, stopping every so often to extricate her feet from the looped foliage. She made about ten meters progress before stopping to catch her breath.

"No need to get too close," Skyhook reminded her. His eye had telephoto.

"Yes, but I might pick up droppings, or some fallen hair or scales."

Some of the rolling "tires" were heading toward her. Each one had several round cranberry-colored spots set in its "tread." The "tread" was composed of suckers that stretched and extended to push in back, orpull in front. "They must be animal-like, 'zooids,' " suggested Andra. "Those red things-could they be eyes?" She counted them, two, three, four in all, before the first came up again. Those eyes must be tough, not to mind getting squashed down.

"If these creatures are zooids," Pelt wanted to know, "how do they feed?"

Skyhook said, "Their suckers ingest the phycoids."

Andra stopped again to pull out her foot. "They sure know how to travel," she wryly observed. "No wonder they never evolved legs." One four-eyed zooid got excited, and took off with remarkable speed; then it suddenly reversed, heading backwards just as fast. These zooids had no "backwards" or "forwards," she thought.

Quantum radioed again. "Andra, how are you holding up? Is your breathing OK?"

She took a deep breath. "I think so." Most of the rats had died from inhaling toxic dust. She resumed her attempt to make headway through the phycoids, and searched the ground for anything that looked like droppings. Overhead, she heard a strange whirring sound. A flock of little things were flying, their movements too fast for her to make out.

"Their wings are turning full around, like propellers," Skyhook exclaimed in amazement. "Why, all these creatures are built of wheels, one way or another."

"Sh," said Andra. "A zooid is coming up close."

The creature rolled slowly over the phycoids, squas.h.i.+ng the golden ringlets beneath it. Andra took a closer look. "There's a smaller ring structure, just sitting inside the bagel hole. I'll bet it's a baby zooid."

The clinging little one rolled over and over inside as its parent traveled. The parent did not seem to notice Andra at all; neither her shape nor her smell would resemble a native predator, she guessed.

The radio crackled again. "We must attempt contact," Quantum reminded her. Any zooid might be intelligent.

Andra held out her communicator, a box that sent out flas.h.i.+ng lights and sound bursts in various mathematical patterns, strings of primes and various representations of pi and other constants. It even emitted puffs of volatile chemicals, to alert any chemosensing creature with a hint of intelligence. Not that she expected much; their probes had broadcast such information over the past year.

Then she saw it: A giant zooid was approaching, five times taller than the others and perhaps a hundred times their weight. As it barreled along, picking up speed, the small striped ones took off, zigzagging crazily before it. The ground rumbled beneath her feet.

"Get back to my cabin!" urged Skyhook. "We'll all get run over."

"Wait," said Pelt. "Do you think it heard us? What if it wants to talk?"

"I don't think so," said Andra, prudently backing off. "I think the smaller zooids attracted it, not us."

A small zooid went down under the giant one, then another. That seemed to be the giant's strategy, to run down as many little ones as it could. At last it slowed and turned back, coming to rest upon one of the squashed carca.s.ses.

"It's extending its suckers to feed," observed Skyhook. "Let's get back before it gets hungry again.""I think that will be a while," said Andra. "It's got several prey to feed on." The rest of the smaller zooids seemed to have calmed down, as if they knew the predator was satisfied and would not attack again soon. Definitely a herd mentality; no sign of higher intelligence here.

Andra resumed collecting phycoids and soil samples, recording the location of each. Deeper into the field, she saw something thras.h.i.+ng about in the phycoids. She made her way toward it through the tangle of looped foliage.

"It's a baby zooid," she exclaimed. The poor little bagel must have fallen out when its parent ran off. Or perhaps the parent had expelled it, as a mother kangaroo sometimes did. At any rate, there it was, squirming and stretching its little suckers ineffectually, only tangling itself in the phycoids.

"Watch out; it might bite," said Skyhook.

"Nonsense. I have to collect it." Andra stuffed her hands into a pair of gloves, then approached warily.

With one hand she held out an open collecting bag; with the other, she grabbed the little zooid. It hung limply, twisting a bit.

Suddenly it squirted something. An orange spray landed on the phycoids, some of it reaching her leg.

Andra frowned. She plunged the creature into her bag, which sealed itself tight. "Sorry about that, Pelt."

"You're the one who would have been sorry," Pelt replied. "That stuff is caustic, as strong as lye. No problem for me, but your skin would not have liked it."