Peace deduced the rest.
The Protectors had gone out in fission-powered ion-drive ships, looking for planets where tree-of-life would grow properly. They had found none; there were few planets that were at all habitable. However, the original expedition would have been equipped for terraforming. Planets had water added, were seeded with algae, were even smashed with small moons to create high ground on the far side, above the thick atmosphere. Meanwhile, the few Protectors that remained on Earth were cultivating mutations, so that a species would eventually arise which would be able to use the terraformed planets.
And some explorers must have met the puppeteers.
Two and a half million years back, the puppeteers must have already had spaceflight—not manned, to be sure, but effective at searching for threats. The Protectors would have realized that their limited numbers could never exterminate the puppeteers before Earth’s breeder population was found and slaughtered. The Protectors wouldn’t have returned to Earth, and they would have killed themselves rather than risk giving away its location. At least one must have made sure of being undiscovered, though, and returned to Earth to warn the Protectors there; and they in turn would have methodically destroyed all signs of technological development. Except the plants they’d modified to produce a multipurpose raw material, unnecessary to the plants’ survival, in their secretions; there were too many of those, intended for availability in all climates, to hunt them all down. The best-known was the rubber tree, so useful it was still cultivated on Earth.
The puppeteers had eventually found Earth, and Kzin, and a lot of less interesting inhabited planets. They had manipulated the two dangerous races’ development. When Phssthpok, another Pak protector, had come from the Core, they’d let him through, to stimulate Earth’s technology to catch up with Kzin’s.
But, thanks to a couple of centuries of Brennan’s interference, Earth developed wrong, becoming too peaceful to survive the discovery of the planet by the kzinti. So the puppeteers had arranged to let kzinti warcraft find human colony ships in interstellar space—something that had happened half a dozen times. Twice, human ships had survived long enough to send home messages about the contacts.
And humans and kzinti alike thought of it as coincidence!
Picture a globe six million miles across, full of air but unilluminated. Add hundreds of floating bonfires, each with a surface area of at least an acre, in all colors, well-scattered. Imagine air jets to push you from one bonfire to another, in straight lines. Now picture other people, all coming from one bonfire you haven’t been to, traveling to various others you haven’t been to, propelled by butane-jet cigarette lighters. You know nothing of cigarette lighters and do not use instruments designed to seek them out. How close do you have to get to one to notice it against the background of bonfires? The closest that two of these skew paths get to each other is in excess of a thousand miles. Now multiply the distances by 40 million, and the bonfire surfaces by 1.6 quadrillion, and ask yourself how the kzinti found human ships in interstellar space six times.
Once would be a miracle to stupefy an atheist. Twice is enemy action. Six times is policy.
The puppeteers had arranged beacons, not recognizable as such, to attract kzinti ships. (Possibly telepathic; the kzinti had the capability far more often than humans, which implied it was latent in the whole species—which would explain why they were so hostile: noise.) Once the First War began, the puppeteers had quickly realized that the human ability to kill anything had been all but bred out of the race, and the humans would lose; so they arranged for the Outsiders to go to We Made It, outside the war zone, and sell hyperdrive to the crashlanders. Probably without telling the Outsiders why. Conceivably without telling them at all—Outsiders followed starseeds, and it would be a simple matter to dump trace elements a starseed needed into a star’s chromosphere.
And while the Outsiders were ambling along at sublight speeds, Wunderland’s population was conquered, enslaved, and eaten.
The puppeteers were powerful and arrogant, which was understandable, but also shortsighted in their meddling, which was intolerable. It might be necessary to exterminate them. If so, it would first be necessary to get them far from human space, as they would doubtless panic and slaughter everything in sight once the procedure began. Doubtless they were aware of the possibility of higher levels of hyperdrive, the next of which was at (if the drive’s manual of operation was based on the assumptions it seemed to be) 6!×4!×2!/10=3456 times the speed of the first level, or near enough to .8 lightyears per minute. It was always profitable to go faster, so they would be doing research already, so she would only have to have a few algorithms published in technical journals to get them out of the blind alleys. A publicity trip to the Core would give them a look at whatever the Pak migration had been fleeing, and they’d run immediately. That would give Peace a few centuries to decide what to do with them.
The kzinti could be disposed of more promptly.
When Peace was too full to eat any more, she reprogrammed and partly rebuilt the autodoc, then got in for a full scan. Brennan had created a human-infecting form of the virus that changed the Pak (or their relatives) into Protectors, and he and his descendant Truesdale had brought it to Home, to prepare a surprise for the Pak Protector scouts they’d lured away from Earth. Peace needed to find out what it did. The results showed there were things Brennan hadn’t mentioned, and that Truesdale most likely hadn’t known.
Each lung had an extra lobe, now, so the right had four and the left three. The lobes were now separated by membranes, so that puncturing one wouldn’t collapse the rest of the lung. Ribs had thickened and spread to accommodate the change. There was now a two-chamber iliac heart in the groin, drawing blood from the lower body. It pumped it directly into the new lung lobes, which oxygenated it and added it to the blood returning from the rest of the body. Running this mix through the original lungs produced blood supersaturated with oxygen, which the expanded brain needed desperately. The original heart developed thicker muscle and redundant feeder vessels, and the extra oxygen kept it from strain. The extra pass through the lungs would also allow her to function when the partial pressure of oxygen in local air was too low to keep an unchanged human conscious.
The lymphatic system had developed one-way valves, such as veins had, so that the fluid was kept circulating by changes in pressure as muscles were used. The spleen had developed into an organ much like the liver in texture, and its new function seemed to be scavenging trace minerals.
The end joint of each finger was now able to move independently of the rest of the finger, like the end of a human thumb.
There was a hard shell contained within each eyelid. The shell was resilient, and opaque. The eye itself had a second lens behind the original. The new lens was normally flat, but could be made concave enough for work as close as an inch from the pupil. The original lens was saturated with a substance which responded to chemical cues in milliseconds, to become tinted (the usual state), polarized, or clear. Without the Protector additives, this chemical turned the lens white, producing cataracts. (Brennan and Truesdale, products of Fertility Board selection, would have known nothing of this, and would sometimes have needed sunglasses.) The pupil could now open all the way to the edge of the iris, gathering far more light, and the retina had grown a tapetum, like a cat’s eye, to give the receptors a second try at the photons. The progressive die-off of the retina’s color-detecting rods was compensated by the trick of tinting the lenses different colors, providing strong contrast. It occurred to her that the instinctive attempt to see this degree of contrast, by unaltered elderly humans, finally explained gingham. The preprocessing layer of the retina was thicker, too; and as a huge amount of new brain growth had been in the optic center, image persistence was longer. A Protector could read a newspaper page held up twenty feet away if the light was good.
The olfactory region of the brain was now almost half as big as the optic center used to be. This, like the fing
er change, was implicit in Brennan’s assertions; a Protector had to be able to distinguish one protein molecule from another when they differed by only one amino acid in one place. The processing involved was tremendous.
The brain had more than tripled in size. The new material at the back of the head was mostly three big lobes of cortex, each one a bigger processing net than one of the human brain’s cortex hemispheres; and the hemispheres she’d started out with had grown as well. One of these five lobes sufficed for routine activity, allowing the rest to sleep when not needed. Processing networks required something akin to a dream state from time to time, or they began giving aberrant results; a Protector must have at least one cortical lobe in dream state just about all the time. A human Protector could have two in dream state, and still be smarter than a Pak Protector going full out.
There had been nerves dealing with facial muscles and genital response, and those nerves were dead and resorbed in metamorphosis. The brain centers formerly connected to them were now sensing with, and sending commands to, new nerves in the improved fingertips. Small wonder if Protectors enjoyed making things.
The lining of the small intestine was thick, and dense with blood vessels. Intestinal tissue was being constantly converted to embryonic cells, and those were entering the bloodstream, attaching themselves to cells that were functioning improperly. Once there, a new cell wrapped completely around the target cell, took up the cell’s proper function, and ate it, digesting its proteins and nucleic acids into individual amino acids and nucleotides. Most of these were released into the blood plasma. The new cells also ate any foreign material, and dead or mutated cells. Bone marrow now produced only red cells—which were some twenty percent more numerous than before, and now had wrinkly surfaces to maximize the O2/CO2 exchange rate.
The virus that was present in the small intestine showed no sign of having ever been capable of infecting a plant. It didn’t do that much to the small intestine, for that matter; but the genes it added produced some really astonishing prions—multifunctional enzymes which, among other things, reshaped other proteins, of similar but not identical sequence, into the same shape as the prion. Back in biochemistry classes she’d been taught that twenty-first-century Earth had waged desperate battles in the lab to wipe out just a few types of prions that had gotten into the food supply. Seeing them at work, this was plausible.
Tree-of-life virus must have infected the plants alone, and turned their proteins into prions. Jack Brennan had developed this virus by reverse-engineering the prions and creating the thing from first principles, and must have been planning to do so from the moment he killed Phssthpok. (That part of his story she believed. The Pak Protector would have sterilized Earth if he’d even suspected humans would turn down tree-of-life.) The prions only worked right on cells that had undergone a certain number of divisions—one of them converted telomerase to a new formulation, and too much of the new stuff—a regulating enzyme—would melt you to a blob, while too little would allow your cellular metabolism to speed up until it cooked your brain. The latter had actually happened to one of the Belters who’d inspected Phssthpok’s cargo.
There were more mitochondria per cell, too. There seemed little purpose in this until Peace made the connection with a genetic disease she’d read about, now absent from the species, that caused mitochondria to accumulate calcium phosphate. In a Protector, it was a storehouse of material for regenerating bone; in breeders, it sapped strength in all tissues on a cellular level by limiting the size of the ATP reserve. It must have been universal at one time—Pak breeders didn’t need stamina, clear heads, or motivation: they had Protectors. Peace recalled that salicylic acid, and its salts and esters, caused mitochondria to store inorganic phosphates, and she determined to stockpile the stuff.
She had used up most of a day getting acquainted with her new condition. Time to get to work. It would be tedious; the annihilation of technological artifacts was so thorough it must have taken some earlier expedition’s protectors weeks, and Truesdale and the Home Protectors had stripped out all ore deposits for their arsenals before the asteroid bombardment, sensibly enough. (The mining trees were a splendid bit of misdirection: the Brennan virus had an affinity for the bark, which was crumbly.)
She went through the hidden parts of the computer’s memory and found references to inventions the UN ARM had suppressed. Some sounded useful. There were no technical details, but a general outline of principles was usually given, and that was enough.
The third day she gave in to her impatience and built an automaton that could perform simple routine tasks, like cleaning rooms or repairing scanners. For the latter task she had to include a device that distorted the force binding the instrument shells, making them pliable enough to reach through; it had been obvious that the puppeteers must have some means of softening GP hulls, as they would never have sold invulnerable warship hulls to aliens. This done, she had the idea of building automata to fabricate parts usable in a variety of items, and judged it worth the time. (Technology doesn’t save labor: it invests it.) Pure elements could be had via the expedient of a conveyor belt, a disintegrator, and a tapered wind tunnel. She dedicated five days to these tasks, then one more for a device that assembled parts to order, and was able to begin work on parts for the exotic stuff. She arranged a foil shell in stasis for workshop housing—some of the mechanisms would absorb stray neutrinos otherwise—and began building various specialized components for weapons of short, middle, and long ranges. Middle range being the horizon.
When the kzinti showed up, she was pleasantly surprised (and just a bit embarrassed for them) to find that she could easily break into their ship’s command codes, which raised the possibility of interrogating prisoners. She shut off the fuel feed to their fusion source, then found mechanical cutouts that prevented total shutdown of key systems, so she broke out something she’d built as a battery charger. It was faster than laying cables everywhere: it drew power out of all nearby sources, or a source it was aimed at, all without the need for broadcasting. It was just the thing to make a ship fall down.
Most of the survivors were an armored infantry group, and the ones who saw her didn’t fight the way she’d expected kzinti to fight; they seemed desperate, rather than fanatical. It dawned on her that a Pak Protector must have landed on Kzin two and a half million years back, and made a really lasting impression. They would have been intelligent by then, but not civilized. Oral tradition would have distorted with every generation, but drawings would be kept up. Some of these troops blew themselves up when it was clear she’d be able to capture them; it was like they expected her to drag them, screaming, back to Hell.
The last survivor was pinned in the wreck; he’d been pretty well-protected, but he was still nearly torn in half. She found the medical supplies and dosed him with things whose labels showed a kzin bleeding, a kzin thrashing around, and a kzin in pain. (Arrows pointing in, instead of stars flying out. Fifty thousand generations of mortal combat for mates had evidently selected for kzinti so healthy that pain was regarded as an unnatural, external phenomenon.) When he became coherent, he asked if her name was [outraged wrathful snarl]. She told him her name, and he did a very strange thing: he pleaded with her. “We only wanted slaves this time,” he said.
She immediately realized, with some amusement, what he understood the word peace to mean, and saw that he too regarded her as some sort of divine avenger; come to slay them all for eating humans, most likely. The word slaves, however, called up old information she hadn’t thought of since college; and everything suddenly fell into place.
How could a species that exterminates all mutated offspring have evolved?
The Slavers had ruled the Galaxy a couple of billion years back, according to Larry Greenberg, a human telepath who’d spent several weeks more or less possessed by one. (It had been released from stasis, due to a level of carelessness that Peace would have found appalling even when she was a heavily-medicated breeder. Paranoia was more com
mon then, and had such a bad reputation that caution was treated as some kind of vice.) They used telepathic control to command other species (the Grogs of Down were their incredibly remote and wildly mutated descendants) and enslave them—hence the term. Their name for themselves was thrintun. (It was pronounced without the tongue ever touching the teeth—a thrint’s teeth were metallic, and razorlike—and for a human it was a fine way to try to strangle yourself without using your hands.) Their principal slaves had been the tnuctipun, who were miracle workers at genetic design. The tnuctipun had produced the bandersnatch, still found on Jinx—they didn’t mutate. The bandersnatch was intelligent, and immune to thrintun Power, and created as a food animal—the big brain was justified by making it very tasty. Bandersnatchi were made to be spies on the thrintun. The tnuctipun had spent centuries developing ways to screw up the thrintun while ostensibly being helpful, and when war finally became open the only counterweapon the thrintun had that worked was amplified Power: they had commanded everything in the Galaxy to commit suicide. Everything that wasn’t immune, in stasis, or too stupid to understand, obeyed.
Greenberg had said there were seventeen other intelligent races—eighteen if you stretched the definition a little. Implicitly, the eighteenth race must have sometimes gotten even clear telepathic orders wrong. The tnuctipun would have been assigned to make them smarter.
They had. It must have been one of their first successes. They came up with a virus that turned vegetable protein into the most amazing prions, and altered the species to start finding it irresistible—but only after reproducing. The desexing wasn’t necessary, and from an evolutionary viewpoint was actually undesirable; selection would work better if reproduction occurred after the development of intelligence. The killing of mutated descendants was another deliberate effort to prevent evolution, and it had worked for two billion years. The loss of appetite when there were no descendants was just a safety feature to keep their numbers down, and the virus’ thallium requirement was a way of limiting their mobility. The breeders’ genes had evidently also been altered so that their brains were hardwired to sympathize with rebels and underdogs. Even today, humans hearing about the Slaver era tended to side with the tnuctipun—who by any reasonable standard were as coldly evil a race as had ever existed. (Kzinti ate intelligent lifeforms because hunting them was such a good challenge, and this was as horrifying a practice as you could find nowadays; but even they would recoil at the thought of creating an intelligent race for use as food.)