SNAFU: Unnatural Selection

by Christopher Golden

  They agreed to perform a cursory search of the town in hopes of finding any clues before heading blindly into the wilderness. Every house was in the same condition. These people had never known what hit them. The attack had come through the broken windows and doors while they were sleeping and their bodies had been removed through the same egresses. There were no bullet holes or spent casings, no discolorations on the walls or ceilings to suggest aerial dispersion, or any other indication of the means by which these people had been overcome. All that remained of them were smears and patterns of blood to mark where they’d fallen and the direction of their posthumous passage.

  Whatever livestock they’d held was gone as well. The stables and pens were vacant, the straw desiccated and dusty. There were no fresh tracks or any other sign animals had even been housed there recently, with the exception of sporadic mounds of fecal material, which Byrne theorized belonged to animals other than those once contained in the pens.

  The spoor was black and runny, a trait caused by a high concentration of blood. The fact the same feces was scattered throughout the town suggested it came from one species, and not one that had been domesticated or housed in the pens or pastures. Richards suggested it belonged to a species of scavenger that had fed upon the victims while they were either incapacitated or dead, which made a certain amount of sense. Byrne was no expert on feces, nor did he have any desire to be, but he couldn’t dismiss the observation that much of the spoor appeared to be older than forty-eight hours, especially that found near the fringes of town by the majority of the empty livestock pens.

  The establishments in what passed for the commercial district were different. There was nothing peaceful about the way the patrons of the ramshackle bars and restaurants had gone. The walls and ceilings were spattered with blood. Tables lay overturned amid shattered bottles and plates. Dried blood flaked from the wooden floor like lichen and formed a brick-red path onto the dirt road where the victims had either crawled or been dragged out into the street. The dirt remained disturbed where many had fallen and struggled to drag themselves in the opposite direction from which their remains were ultimately taken.

  Byrne performed the ELISA assay on another half-dozen blood samples he’d collected from various points around town while the others explored the military barracks. It appeared as though the majority of the forces had been dispatched before the siege. Bunks remained perfectly made and footlockers were half-empty. There were no boots or fatigues to be found in most of the buildings, which reminded Byrne more of mobile homes stuffed full of cots than actual quarters. The inner walls of the guard shack were riddled with bullet holes and covered with blood, as was the westernmost barracks, inside of which it looked much like all of the other dwellings.

  Graves was able to determine that the forces had been dispatched three weeks ago to Koindu, a town forty miles to the northeast on a finger of land thrust straight into Guinea on one side and Liberia on the other, presumably as a deterrent to the advances of Boko Haram. Richards speculated the jihadists must have gained knowledge of the maneuver and swept southwest along the banks of the Moa River, which flowed directly behind the outpost.

  The assays had provided no new information, but had confirmed the presence of IgG and IgH antibodies in comparable amounts. It was only while waiting for the others to complete their search of the barracks that Byrne decided to isolate the blood from the spoor near the front gates, where Anthony remained as his personal guard, and run it through a separate ELISA assay. The results solidified a theory that had yet to fully form in his mind.

  “Interesting,” Byrne whispered.

  “What?” Anthony said. He peeked back over his shoulder before returning his attention to the gate blocking the lone road into the outpost.

  “This blood sample. From the stool. It has elevated levels of eosinophils and acetylcholine receptor antibodies.”

  “So what?”

  “Acetylcholine receptors purvey chemical signals from the nerves to the muscles. Eosinophils are the white blood cells responsible for combating allergic responses, especially in relation to the respiratory system.”

  “What are you getting at?”

  “The nervous system in the first thing affected by envenomation, followed in short measure by the respiratory system. Think of a cobra. After it bites its prey, its venom goes straight into the bloodstream and to the nerves, where it blocks the signals from the brain to the muscles, causing paralysis. Immune responses work much more slowly. The body produces increased amounts of white blood cells in response to the elevated levels of histamine caused by the venom. Eosinophils, specifically, help combat inflammation of the lungs, which is the ultimate denouement of a snakebite. First the prey can’t move, then it can’t breathe. That might be an oversimplification, but you get the gist.”

  “We already knew we were dealing with a type of venom. That doesn’t change anything.”

  “But it tells us a lot about the animals that produced the spoor.”

  “Great.”

  “Don’t you see? They’re ophiophagic. The elevated levels of eosinophils and acetylcholine receptor antibodies aren’t present in the blood of the victims, but they’re in high concentration after passing through the bodies of the scavengers. They’re not sensitive to the venom because they already have the antibodies to combat it. Like a mongoose or an opossum—”

  “A honey badger.”

  “Exactly.”

  “But none of those are large enough to prey upon people, no matter how incapacitated they are.”

  Byrne stood and paced the front deck of the empty barracks. Richards and Warren emerged from behind a stand of trees on the far side of the field, while Graves appeared from the direction of the river.

  Anthony was right. He couldn’t think of a single ophiophagic species that preyed upon man, nor could he think of one that scavenged. Ophiophagy was a specific adaptation that evolved based on the prevalence of venomous sources of food. So what did that imply?

  “We’ve stalled long enough,” Richards said.

  Byrne understood what he meant. The time had come to follow the trail into the jungle, where any number of potential dangers could be lurking behind any tree trunk or waiting in the trees with weapons trained down on them. They’d be sacrificing every advantage the open space afforded.

  “Tell me you learned something we can use,” Warren said. He nodded toward Byrne’s case.

  Byrne shook his head and glanced at Anthony. He was reluctant to share what he’d found until he was able to make sense of the results. They didn’t make sense, at least not in this context. Either the species responsible for the spoor was a scavenger that had seemingly overnight evolved the ability to manufacture antibodies in the levels required for the ingestion of high quantities of venom, or the production of antibodies was the adaptation of a predatory species that had somehow developed the ability to produce venom.

  * * *

  2:09 pm GMT

  The rain fell in rivulets through the canopy, hitting the muddy ground with a sound like a rushing river. Byrne skirted the sucking puddles and battled through the wet shrubs. Guinea fowl called from the brush and scampered away when they neared. Macaws squawked and swifts darted through the treetops. Byrne watched for the monkeys he’d heard on Dr Odongo’s recording, but didn’t see a single species that didn’t have wings or scales.

  The trail they’d been following since leaving Daru was still evident, although by now it had become a narrow stream, obscuring whatever footprints might have survived the parade of bodies being dragged over them.

  That was the detail that most bothered Byrne. There were any number of ways to relocate a large quantity of remains – loading them onto a truck, airlifting them by chopper, or even pulling multiple victims on a makeshift travois. Dragging individual carcasses across such a large distance and over terrain this brutal seemed like the least practical option. There had to be a method to this madness, otherwise heaping the remains on top of each
other for mass incineration would have been the fastest and most efficient means of elimination. The only reason to go to this much trouble was if whoever was responsible intended to keep the bodies, for whatever ghastly reason. If the attack on Daru was just a test of whatever mode of venom dispersion they employed, then the last thing Byrne’s detail could afford was to let the enemy perfect its weapon. Chemical agents were bad enough; a biological weapon that left no residue, could easily pass through airport screening, and was capable of completely incapacitating an entire town in a matter of hours without allowing more than token resistance from trained soldiers would be catastrophic in the wrong hands.

  If only Byrne had access to even one of the victims. Maybe then he’d at least be able to determine the means of envenomation. An airborne mode of delivery would almost certainly be fatal as there wouldn’t be time for the victim to generate an immune response. The sudden and acute respiratory inflammation would cause more bleeding than they’d seen in town and would manifest as a mist from coughing or pools when the diaphragmatic reflex waned and anoxia caused the loss of consciousness. It seemed the least likely path to weaponization, but how else could so many people be overcome in such a short amount of time? It wasn’t even possible to overwhelm a population so large without an invading force numbering in the hundreds, if not thousands.

  Indigenous tribes in the Amazon had been using poison-dipped darts and arrows for millennia, but even they didn’t have the skill required to hunt thousands of people without leaving so much as a single dart behind. There had to be some other form of mass dispersal, and the fact he couldn’t think of it scared him more than anything else. What kind of nightmare were they walking—

  Impact from the side.

  Byrne hit the ground. Hard. The weight of his assailant nearly knocked the wind out of him. Before he could cry out, he was seized by his shoulders and rolled onto his back.

  Graves thrust his face shield against Byrne’s and mouthed the word Quiet.

  Byrne nodded.

  Graves widened his eyes as though seeking confirmation.

  Byrne mouthed the word Okay and Graves climbed off of him. By the time he rolled over, Graves had vanished into the shrubs. Byrne could barely see Warren off to his right. The soldier lay prone in the mud, his shoulders and rear end breaching the surface of the brown water, the barrel of his rifle propped on the branch of a thorny shrub with green-spotted fruit. The angle of his sightline was obscured from Byrne’s vantage point. He crawled around the wide buttress roots of a ceiba tree to get a better view.

  At first, all he could see were the same trees as everywhere else. It was only then that he realized he could no longer hear the pheasants scurrying invisibly through the brush or the trumpeting of hornbills from the upper reaches. The only sound was the pattering of rain on the leathery branches and dribbling onto the saturated detritus. And beneath it, a faint buzzing sound he’d been so lost in thought he might not have ever heard.

  The flies were fat and black and only occasionally appeared through the screen of leaves and flowering shrubs. There was a small clearing where a tree had fallen and created a light gap. Graves materialized from the forest and crept forward with his rifle seated against his shoulder. The rain made clapping sounds on his isolation suit. A cloud of flies erupted from in front of the soldier. He waved them away, lowered his barrel, and stared at the ground. When he looked back at the others, the expression on his face was unreadable.

  Richards rose from the bushes mere feet to Byrne’s right. He’d been so well hidden Byrne hadn’t even sensed he was there. Warren pushed himself from the mud and preceded the captain into the clearing. Anthony appeared beside Byrne as he followed.

  Byrne pushed through branches so heavily thorned he feared they might pierce his suit, and stepped around Warren to get a better look at what lay on the ground before him. The flies tapped against his face shield as he stared down at the dead animal. Its skin was like parchment and taut against its prominent bones. The level of desiccation made it appear almost mummified, as though it had been dead for weeks and left to rot beneath the blazing sun, not in an expanding puddle of rainwater than had to be a good foot deep. Byrne knew better, though. He’d seen this long-horned bull on a satellite image taken a mere thirty-six hours ago.

  * * *

  4:18 pm GMT

  Richards argued the bull could have come from a different herd. Byrne had been unable to prove otherwise, but couldn’t shake the feeling this was one of the cattle that had escaped from the pen at the edge of town. Further inspection had revealed both of its hind legs were dislocated at the fetlock and hock joints, which made them appear oddly strait and elongated, as though they’d been pulled with extreme force. One of its horns was broken; the fracture line was fresh with no sign of callus formation. The rain had washed away any indication of the mechanism of its death or how it had come to be in the clearing.

  Raising its head by the broken horn revealed a large, bloodless wound on its neck. The muscles and tendons stood out like wires. It looked like a scavenger had bitten into its neck, and then thought better of it. Again, Byrne wished he had the human bodies for comparison. Or maybe a sample of blood to run through the ELISA assay, without which it would be impossible to prove the bull hadn’t been attacked by a wild animal weeks ago and left to decompose in the clearing, despite the fact that whatever killed it had made no attempt to consume it.

  Graves proposed it had mangled its own legs by stepping in the burrows of some ground-dwelling animals – it happened all the time on his parents’ ranch back home, he said – and it had ended up using its formidable horns to defend itself from predation while it wasted away. The scavenging must have only commenced when the rain started and the bull bled the last if its lifeblood into the puddle that formed around it.

  The others agreed it was a plausible scenario. Byrne, however, continued to mull it over as they advanced deeper into the jungle. The rain slowed, but the ground had already drunk its fill and supported muddy puddles that often concealed the trail. Progress was slow and treacherous. It felt as though they’d traveled ten miles from Daru, but according to Richards’s GPS they were barely over three. A fresh batch of aerial reconnaissance from an ordinary military-grade satellite showed the town just as they’d left it, only wetter. The streets were bare and there was no sign of life anywhere. The surrounding forest remained impervious to the camera and they still had several hours before the GEOS 2 was overhead, neither of which did them the slightest bit of good.

  Byrne knew it was still too soon to share his burgeoning theory, especially considering how ridiculous it sounded inside of his head. It started with the inference he’d drawn from the stool sample. Whatever animal left its spoor must have attempted to scavenge the victims while they were still alive for there to be such a high concentration of blood in its feces. It would take a brazen animal to even attempt something like that. Vultures were known for such acts, but the fecal material was definitively mammalian, which considerably narrowed the field. And considering there were no known ophophagic scavengers, it meant they had to be dealing with an opportunistic predator, one roughly the size of a dog, judging by the size of its spoor. And if a species that large had somehow evolved the capacity not for the consumption of venomous species, but rather for its production…

  Byrne shook his head to clear his thoughts. That line of thought was patently absurd. There had to be another, more logical solution; he just needed to come at it from a different angle. He was exhausted and hadn’t slept in several days. Things would undoubtedly make more sense after a good night’s sleep, although he wasn’t overly optimistic that would happen anytime soon.

  The canopy remained silent, save for the dripping of condensation working its way inexorably to the ground, which did nothing to suppress the sounds of their passage. Despite their attempted stealth, Byrne could pinpoint the locations of the others around him, if only by the whispering of leaves grazing their isolation suits or the faint slur
ping of boots being drawn from the mud. Byrne was getting better at concealing the sounds of his passage, but he had a long way to go to catch up with the others, who maintained a diamond formation around him.

  The intonation of the dripping changed. As did the faint whistling noise of the wind through the trees.

  Byrne slowed and surveyed his surroundings. The branches overhead nearly blocked out the sunlight, only a fraction of which reached the ground in palpable columns of light. It diffused into the upper reaches ahead of him, dramatically lighting boughs that appeared noticeably less dense and shivered on a breeze he couldn’t feel through the oppressive humidity.

  He resumed walking, alternately glancing from the trail to the treetops. The others passed through the bushes like specters. Their pace slowed. They obviously recognized the same thing he had. There was a change in the air. The goosebumps rose on his shoulders and neck. He felt the faint movement of air, but there was something else, something he couldn’t quite define. He watched the branches overhead. There was no sign of life. No motion. No sound. Even the metronomic dripping seemed to have ceased. And yet still it felt as though something was up there. Watching him. Tracking his every movement.

  Byrne looked back down and pushed through a wall of saplings taller than he was.

  Richards stood in front of him, silhouetted against the golden aura that passed through the canopy. The others appeared to either side of him and stopped when they reached the edge of a sheer cliff.

  The whistling of the wind almost sounded like it came from beneath them.

  Byrne approached the ledge and looked down into an enormous pit like the one into which they’d parachuted, only this one was so deep the light barely reached the bottom, where it shimmered on the surface of a murky brown pool.

  The trail they’d been following since Daru terminated at their feet.