The wall at the edge of the village was high, over ten meters. Nothing of the terrain or wildlife beyond was visible. Harlan felt the tension starting to build. He had seen precious little out the window of the shuttle coming in, only dense forest. Sensories of African journeys were difficult to come by, even for a lieutenant colonel in the Iotan Army. The bottom line was that he didn't know what to expect. Olivia led him to the airlock. They walked into the small chamber.

        Olivia started to pull her masked hood over her head when Harlan put a hand on her arm. She didn't appreciate the gesture.

        "We need to talk," he said.

        "I know. I'll save you the trouble."

        "Really?"

        "You were going to give me the lecture about how you're the boss and what you say goes. If we're ten meters from our goal and you decide it's too risky to continue, we turn around immediately and I don't argue. Something like that?"

        "Well, yeah."

        "It's not like that here. I'm in charge." Harlan's temper cracked a little. Olivia held up a hand. "I know more about what's on the other side of that door than anyone alive, and you know nothing. Am I right?"

        Harlan nodded slowly.

        "If there is something out of the ordinary, a seismic event, a medical emergency, a sudden storm, then, yes, I will defer to you… but anything to do with the wild itself? I'm the expert, I'm the lead, I dictate what happens and how. I requested backup because it is standard procedure, but it is not an opportunity for you, it is a responsibility for you, and I define where your responsibilities begin and end. Is that clear?"

        Harlan paused. "That's quite a speech."

        "I've given it before."

        More silence filled the little room.

        "Anything to do with the wild, you're the boss. Otherwise…"

        Olivia nodded. She pulled her hood up. Only her eyes were visible now, through plastic goggles built into the suit, but they still said volumes about her opinion of Harlan and her estimation of his worth. He grinned as he pulled on his own hood. Olivia opened the door.

        The light was bright, so he didn't see much at first, but the smell hit him like a roundhouse. It was like the smell he sensed in the shuttle bay, but many times stronger. He was reminded of curry, but that wasn't quite right. It was definitely a spicy sort of smell. The mask he wore wasn't designed to filter the local atmosphere, which was nontoxic to humans, merely to provide him with the oxygen that Africa lacked.

        It was also cold; he estimated at least ten degrees below freezing. He hoped the gray bodysuit would be warm enough. Olivia walked out, and Harlan followed.

        The first thing he saw as his eyes grew used to the daylight was that the ground was moving. He could feel it under his boots, shifting and pulsing. He looked down and saw that the ground was that same color that he was starting to think of as African Gray. As he looked at it closer, he saw that he wasn't really standing on ground. It was a writhing mass of creatures. Some were long and round, python or boa size. Others were flatter, scuttling like beetles. Many worms slithered in between. Other stranger shapes, more geometrical: bugs shaped like squares and hexagons. Thinking he'd walked in the wrong place, Harlan sidestepped to the left, but it was more of the same. To the right. Forward. Everywhere. He looked at Olivia in alarm.

        "That's the ground. There's no soil," she said.

        "No soil? Rocks?"

        "Not that we've found. Obviously there's a planetary crust somewhere underneath, but biomass is all we've seen so far on this planet."

        Harlan was fascinated as well as revolted. The flat no-man's-land between the high walls of Bouyain Village and the beginning of the jungle was a sea of living (breathing?) life. And, most importantly, it seemed to ignore him.

        "Am I hurting anything?"

        "Probably. But if you do crush a nematode or a crustacean, it will be eaten by something else. Nothing is wasted. Come on." Olivia trudged forward through the muck toward the trees that marked the edge of the wilds. Harlan followed, wary. The trees weren't very tall, not even five meters as an average, but they sported a very thick canopy of leaves. The leaves were a little greener than African Gray, but still nothing like an oak or an elm. There was more strange geometry to them, too. They looked like some computer model of a leaf where the designer couldn't quite get the fractals right.

        The trunks of the trees were almost metallic, very cylindrical and smooth. No knots that Harlan could see, at least not in the few he walked under as he followed Olivia. He knocked on one with a knuckle, and was disappointed when the tree didn't ring like a bell.

        The canopy made the jungle dark, dimmer than twilight. Olivia hadn't turned on a lamp, so Harlan followed her lead. Deeper into the wild, the smell got heavier, which Harlan hadn't thought possible. He also wasn't pleased to see that the floor creatures were slithering and skittering their way up each and every tree trunk. There was so much movement all around him, and all of it in minute shades of the same dull color; his eyes began to feel the strain of sorting out this troublesome data.

        "It's hard to see."

        "Don't turn on your lamp."

        "I know. It's not that it's dark; it's hard to see. You know what I mean?"

        "You get used to it."

        When? After three years of field study, Harlan guessed. He focused on the clear, unwrithing shape of his guide. She hiked with a steady, comfortable pace. Maybe defining the journey as "a day" wasn't so ridiculous after all.

        "So what's dangerous out here?" he asked.

        "Everything."

        "Okay, I'm scared. Well done. But are there any big carnivores? Dinosaurs or something?"

        "Nothing here is as evolved as that. The Bouyain trees are the most sophisticated living thing we've found yet."

        "Bouyain trees, huh? Only find them in these parts?"

        "Only find them around Bouyain."

        "What are these?" Harlan pointed to the trees ahead.

        "Different."

        Harlan took a closer look. What he could see of their trunks, behind the profusion of crawling and sliding creatures, did look a little different. The grain was a little wider, and the leaves seemed different, too, almost square.

        "They're similar."

        "Yes."

        A tree to the left was wrapped like a barber pole by a snake as thick as Harlan's leg. He couldn't see the creature's head, didn't even know if it was up above the leaves, sunning itself, or down in the soup, feeding. Something about the snake's skin seemed odd. It had a diamond pattern of scales… Harlan thought back to the first snake he'd seen, the one he'd stepped on. It looked like it was the same size, and the scales looked the same, but the first one had been striped. Harlan was almost sure. The stripes were hard to see because they were a change in texture, not in color. But he knew they weren't diamonds.

        "How many species are there here?"

        "Species is not a valid concept on Africa."

        "What?" Harlan stepped up his pace so he could walk at Olivia's side. "There are thousands right here, it looks like."

        "No, there are trillions. On Earth, species was defined as a collection of creatures that can interbreed. That made sense on Earth because the points on the evolutionary trail that led to viable life were few and far between. There were marmosets and there were humans. None of the steps in between survived, and marmosets and humans couldn't mate."

        "You know, there are still plenty of people and marmosets on Earth. You don't have to use the past tense."

        Olivia ignored his rebuke. "All life was neatly partitioned into clumps of genetically similar beings. But what would it be like if there were millions of creatures, spanning the gap between a marmoset and a human? You could breed any two of them if they were close enough on the path of evolution. You couldn't define a species the same way."

        "That's what's happening here? We're seeing all the evolutionary steps at once."

        "I suppose you could simplify it that way. We deal in a fuzzy version of biology that's not about classification but relation."

        "Relational biology. I get it. So what's different here? Why aren't any species dying out?"

        "That's not the question. Remember, there are no species." She patted a tree as she walked, almost like a pet. "Each angiosperm is its own living experiment. The question isn't why they aren't dying. They are. All the time. You're killing some right now."

        Harlan was reminded of the mat of life he was walking across. Looking down, he noted that the collection of creatures already seemed very different from what was near the airlock this morning. The flat beetles had given way to spidery contraptions with seven legs and an ungraceful gait. The worms were few and far between, replaced by something more like leathery jellyfish.

        "So then what's the question?" he asked.

        "The question is, why are they evolving so fast? But the answer is easy. Radiation."

        "Radiation?" Harlan was shocked out of his biology lesson. He hadn't been in active service during the war in Brazil, before Hermione left Earth, but he had friends that were. Many of them hadn't survived a year after exposure to nuclear fallout.

        "You've had your DNA capped, right?" Olivia asked.

        "Yes. That's standard practice for soldiers. But still—"

        "It's standard practice for African researchers as well. You're safe. The wildlife here is suited to an environment of constant solar radiation ten hours every day, but it's not immune. Every generation spawns demonstrable changes. We don't call them Bouyain trees because they live near Bouyain Village. We made them."

        "You made them? You've been tampering with the—"

        "No. We didn't engineer them. We built the city. We disturbed the environment. Every creature living within fifty meters of the city has adapted to the peculiarities of living close to a human settlement. The heat we generate, the gasses we expel, the radio waves—none of these things are deadly, but they have an impact. We're having an impact right now, walking to the spring."

        "I've been meaning to ask you. How do you know the spring is there?"

        "Research."

        "Yeah, that's great. Thanks. And I was worried we were on a wild goose chase."

        Olivia was clearly annoyed, but not enough to stop walking. Harlan had to admire her for that.

        "We have done careful analysis of the relative moisture content levels of the local wildlife, tracking them in many directions from the village. We have also tagged a few hundred animals and tried to determine their migratory habits, but that has been only a marginal success. Still, all the evidence indicates the presence of a spring that way." She pointed to make herself clear.

        "Why not just take satellite pictures?"

        Olivia waved a hand at the ceiling of leaves. Harlan looked up, noting that the leaf shapes here were more like notched ovals.

        "There are other kinds of analysis you can do other than ordinary light. With radar—"

        "With radar, you'd get nowhere."

        Harlan was starting to think that he was getting so frustrated with Olivia that he was seeing spots, but there were some sorts of little creatures flying around in front of his face. He tried to wave them away; it did no good.

        "We call them mites, but they really have little in common with Earth arachnids. In fact, they don't have legs."

        "Where'd they come from?" Harlan was having a difficult time not swatting at these things, but he knew he'd just look like a fool if he did.

        "They don't like the area around the village. There are plenty of things that don't like the area around the village."

        "So it's going to get worse."

        She nodded. He thought he saw the hint of a smile in her eyes. Maybe she did have a sense of humor stuffed away inside all that precocious blather.

        They stopped at midday, after two hours of hiking. Since there were no rocks or tree stumps, Olivia merely took a seat on the "ground".

        "How can you do that?" he asked.

        "Do what?"

        "Sit there."

        This area had nothing like the pythons near the village. That niche seemed to be filled by armies of twenty-centimeter-long tank-like bugs with, Harlan tried to count, twelve double-jointed legs. He didn't see a head on the creature. One of these brutes skittered toward Olivia and Harlan almost shouted to her, but it took a right turn when it got near her and burrowed down into the muck on some unspeakable mission.

        "They don't have eyes, do they?"

        "No. The solar radiation isn't forgiving to optical nerves, so nothing here relies on light."

        "That's why it's all the same color. There's no point in differentiating, so Mother Nature didn't bother."

        Olivia nodded. She lifted her hood enough to take a sip from a water bottle, then tossed the bottle to Harlan, quickly lowering the hood again. He mimicked her, and returned the bottle. He was tired, but he still couldn't bring himself to sit down, especially with those tank-bugs roaming around.

        "Why does radar get you nowhere?"

        "What?"

        "Earlier. You said radar gets you nowhere?"

        "The leaves bounce it, scatter it everywhere."

        "The leaves?"

        Before looking up, Harlan tried to guess what sort of leaves he'd see this time. He imagined a Y-shape with little spikes. He was disappointed to see something like a blocky maple leaf.

        "They're loaded with metals. Indium, gallium, silver, gold, palladium—"

        "Silver and gold?"

        "Yes. This planet, the whole system is lousy with them," Olivia said. If she knew the value those metals had on Earth, she didn't show it.

        "But no iron."

        "How'd you know that?"

        "I was told a compass is useless here. No magnetic field."

        "That's right. A little more iron and some lead, and maybe the radiation wouldn't have such an effect on the plants and animals here."

        "That or oxygen in the atmosphere," Harlan suggested.

        Olivia didn't like something about that comment. She stood up, bracing herself on the rough shell of one of the tank-bugs. The little beast seemed annoyed, but unhurt. It scurried away. And so did Olivia. Harlan was left to follow, wondering why mentioning oxygen was a sore point.

        There were groups on all the worlds around Iota that thought Africa was being wasted. They were radical types, far from the center of any political party. Most people accepted the rules of colonization without question. To Harlan, it seemed ludicrous to agree to be frozen for seventy-five years and brought to an entirely new star if you weren't on board with the program. And rule number one was, essentially, "Thou shalt not destroy local life." Obviously some trees and worms and tank-bugs were killed to build Bouyain City, but they weren't destroyed as a species. (Well, maybe they were, but Harlan didn't want to focus on a technicality.) Rule number one made it clear that Africa wouldn't be terraformed.

        News from other systems was watched with polite disinterest by most everyone around Iota; Harlan knew that one other stellar colonization ship had to turn around when it found all the habitable zone planets in the target system were already teeming with life. That was going to be an unhappy bunch of people when they got back home. And that star was farther from Earth than Iota. Their round trip would eventually take over two hundred years.

        There was a question on the form that everyone had filled out when they applied for a berth on Hermione. The question was asked before placement on any of the colonization ships. It read, "In the event of a mission failure, do you wish to be revived on Earth upon return, or given priority berthing on the next outgoing colonization ship?" Harlan had chosen "priority berthing." When he woke up, he wanted it to be away from Earth, wherever (or whenever) that might be. In a moment of idle curiosity a few years ago, he had accessed the Hermione's records. What was left of her was still revolving around Asia, at a prudent distance from all the Asian moons, sleeping peacefully, waiting in case another journey was required. Harlan broke Hermione's security easily enough and queried the files of the colonists to find out the most common answer to that question on the form.

        Eight-five percent asked to be revived on Earth if something went wrong. These were not people who gave up on the idea of home very easily.

        What Harlan didn't know, and in fact the Iotan Army didn't know either, was how many of the people currently calling for the terraforming of Africa were preemies, and how many were native Iotans. Harlan thought that was a very important question.

        Maybe oxygen was a sore point because it would be the first change in a terraforming effort on this planet, a change that would kill every form of local life as quickly and efficiently as if Earth had been smothered in carbon monoxide. Probably more efficiently.

        Harlan rushed to catch up with Olivia. He found himself swatting at flying things more often. The mites were still there, but they were now joined by larger bugs that looked a little like flying chick-burs. He couldn't see wings or antennae or heads, but each of these little creatures was covered in spikes. He realized that he had dozens of them already snagged on his suit, and he couldn't brush them off. Shoving at them just moved them around.

        Olivia noticed Harlan's concern. "We have a spray. We'll get rid of them before we camp. Keep moving."

        "Sure thing."

        Harlan felt the chick-burs edging under his duffel and tried to ignore them.

        Something about the way ahead was confusing to Harlan's eyes. He was, he had to admit, getting used to seeing an ever-shifting world painted in very delicate shades of one color, but there was a fog ahead. Or maybe some sort of heat illusion? That didn't seem likely in the subfreezing air. Olivia stopped, so he stopped. He ran a hand over his mask, in case it had fogged up. It was like there was nothing beyond where they stood. A line in the jungle was the demarcation point of oblivion.

        "I didn't know there was a wall out here," Olivia said, clearly annoyed. She took off her backpack and sat on the ground, dejected.

        "A wall?" Like any optical illusion, once the trick was revealed the picture became clear. Harlan realized what he was seeing. It was a wall, its top just higher than Harlan's reach. It was roughly finished but sturdily built, a little thicker at the base than the top, which was rounded. He could imagine something like this in a primitive village on Earth, built from lime and mud and straw. The scale was impressive. It extended straight as an arrow right across their path as far as he could see in either direction.

        "I don't get it," he said. "I though you only built villages here."

        "We didn't build this. No one built this. It's alive."

        "What?"

        Harlan took a tentative step back, almost tripping over a thick-bodied scuttler shaped like an equilateral triangle and sporting somewhere around thirty legs. The scuttler picked up speed and ran, away from Harlan and away from the wall.

        "Can it hurt us?"

        "No," Olivia said, "but it is a problem."

        The wall still looked manufactured to Harlan, even after he knew it was a living thing. He walked up to it, inspecting its surface, which was kind of like stucco, clearly random in design, but so uniformly random that he could imagine a painter toiling for hours to get the look just right. He touched it with his index finger… and his finger stuck.

        "Olivia?"

        She looked up, now concerned. "I didn't say to touch it!"

        Harlan pulled, but the fabric of his glove was glued to the wall. He put his other hand flat against the wall to get better purchase.

        "Don't!" But Olivia was too late. The leverage did no good, and now Harlan had both hands welded to the wall. "Be still! I don't want you trying to push off with your foot now."

        "Fine. How do I get out of this? What's this thing going to do to me?"

        "It's going to digest you for a few years. You have to take off your gloves… carefully! If you get bare skin on that thing, it's not going to be pretty."

        The first glove came off easily. As he pulled his hand out, the glove flapped down and remained plastered on the wall. His other hand was tougher. He had to wiggle his fingers back and forth for a good minute before he was free. He backed off quickly.

        "So the phrase 'Can it hurt us?' has some other meaning for you?"

        Olivia was searching through her pack. "Put your hands under your arms."

        "It's cold, but—"

        "Do it!"

        Harlan was about to follow her instructions when something landed on his left hand. It was almost a butterfly. It had a short, thin body and four feathery antennae. The wings were different, though, not the graceful ear-shape that he remembered from swallowtails and monarchs. These were right triangles. It was as if a translucent square, hinged down the middle, was sunning itself on his hand. The wings beat slowly. This was the first thing Harlan had seen on the planet that wasn't unsettling or frightening or hideous.

        "It's cute."

        "It's going to bite you." Harlan's right hand, almost of its own volition, reached up to smack the little bug, but Olivia added, "You'll die if you kill it."

        "Okay, what are you—" The creature, with teeth or claws or something else even more baroque that Harlan couldn't see, bit into the back of his hand. It was painful. Gunshot painful. Migraine painful. It took every ounce of his strength to not bat the thing away. It was difficult to remain standing. Olivia waited, holding the spare gloves she'd found.

        After three seconds, the butterfly released its grip and flew off. Olivia rushed over and covered Harlan's hands. The pain seemed to fade very quickly.

        "Explain." Harlan was starting to lose his patience with this world.

        "It sensed your smell, it landed, it tasted you, it didn't like how you tasted, it left. Keep covered from here on out."

        "Why shouldn't I have just killed it!? If this is about saving the damn creatures, I'll—"

        "If you had killed it, the others would have smelled its death, and they would have attacked you, suit or not. And they wouldn't care how you tasted."

        "The others?"

        Harlan looked around, stunned to realize that there were thousands of the flittering squares above him, floating in and out of the tree leaves above. In fact, the leaves here were a triangular shape similar to the butterflies' wings. If he didn't know what he was looking for, he would have assumed it was simply a windy day.

        "They're a colony? A hive?"

        "Not really. It's very basic instinctual behavior. They don't seem to cooperate in any other way. Of course, we could be missing something, but we don't think they're as social as bees or ants."

        "Uh-huh. That's great. If you're worried about too many people coming here and wrecking the planet, just tell them about those guys."

        "It's all in the literature, if you had bothered to read it."

        Harlan paused, listening.

        "What?" Olivia asked.

        Harlan shushed her and did a slow spin. Something had caught his attention. Some sound that shouldn't have been there. Something human. Another faint whisper of conversation drifted to him. It came from the southwest, along the wall. He gestured for Olivia to follow him, quietly. Thirty meters along, he saw them. A man and a woman, dressed like Harlan and Olivia; they were doing something to the wall. They didn't seem to be concerned about making noise, so Harlan bent into a crouch and moved closer.

        Whoever these people were, they were prepared. The woman carried something like a rolled up carpet and placed it against the wall near the jungle floor. She carefully unspooled it upward, keeping it straight, making sure there were no gaps. When it was flat against this side of the wall, held in place by the wall's sticky surface, she gave it a shove, sending the rest of the carpet rolling up and over the top. She pressed a button on the side of the carpet. Hand and foot holds sprouted from the surface of the mat.

        "Clever," Harlan whispered.

        "I don't know them," Olivia said.

        The man, a large fellow, broad shouldered, muscular, wearing a colossal backpack, climbed up the wall using the silver holds. He sat astride the wall, looking down on the other side. He gave the woman a thumbs up and climbed down out of sight. The woman followed him up and over the wall.

        Harlan and Olivia waited for a minute or so, then moved up to the makeshift climbing surface.

        "They're headed for the spring," Olivia said.

        "How do you know that?"

        "They have to be from Bouyain Village. The nearest settlement is a thousand kilometers away. And for them to be traveling this close to our path is too much of a coincidence."

        Harlan thought about it for a second. "You're right."

        "We have to stop them," Olivia said.

        "Why?"

        "They aren't with the ABRS; they must be energy scouts."

        "Energy scouts? You make this stuff up as you go, don't you?" Harlan asked.

        "Do I have to spell everything out for you? What do you think this spring is?"

        "A place where animals drink. Water comes up out of the ground."

        "I never said there was water here," Olivia said.

        "You said you tracked water levels in the local animals."

        "I said I tracked moisture levels. There is no water on Africa."

        "That's not possible."

        "There is a hundred times more biomass on this planet than Earth. Very few things here live to more than five or six years old."

        "You mean Africa years or Europe years?" Harlan asked. He knew enough about her now to assume she didn't mean Earth years.

        "It doesn't matter. Don't get sidetracked. That's a lot of things living and dying all the time. What do you think the lower layers of the planet are like under us?"

        "Gray."

        "I told you all we've ever seen of Africa is living matter. Even the village foundations were set down on the felled trees of the initial survey teams. Deep down, under us, is layer after layer of dead biological matter, pressed and crushed by the weight of the living. What's going to spring up out of that?"

        Harlan felt a shiver of realization.

        "Oil."