“Why not build more cats?” Marin suggested.
The executive smiled nastily. “You weren’t here when we opened the doors. The warehouse was swarming with rats. How many robot cats would we need—five, fifteen? I don’t know. Anyway the engineer tells me we have enough parts to build three more cats. The one lying there can’t be salvaged.”
It didn’t take an engineer to see that, thought Marin.
Hafner continued, “If we need more, we’ll have to rob the computer in the spaceship. I refuse to permit that.”
Obviously he would. The spaceship was the only link with Earth until the next expedition brought more colonists. No exec in his right mind would permit the ship to be crippled.
But why had Hafner called him back? Merely to keep him informed of the situation?
* * * *
Hafner seemed to guess his thoughts. “At night we’ll floodlight the supplies we remove from the warehouse. We’ll post a guard armed with decharged rifles until we can move the food into the new warehouse. That’ll take about ten days. Meanwhile, our fast crops are ripening. It’s my guess the rats will turn to them for food. In order to protect our future food supply, you’ll have to activate your animals.”
The biologist started. “But it’s against regulations to loose any animal on a planet until a complete investigation of the possible ill effects is made.”
“That takes ten or twenty years. This is an emergency and I’ll be responsible—in writing, if you want.”
The biologist was effectively countermanded. Another rabbit-infested Australia or the planet that the snails took over might be in the making, but there was nothing he could do about it.
“I hardly think they’ll be of any use against rats this size,” he protested.
“You’ve got hormones. Apply them.” The executive turned and began discussing construction with the engineer.
* * * *
Marin had the dead rats gathered up and placed in the freezer for further study.
After that, he retired to the laboratory and worked out a course of treatment for the domesticated animals that the colonists had brought with them. He gave them the first injections and watched them carefully until they were safely through the initial shock phase of growth. As soon as he saw they were going to survive, he bred them.
Next he turned to the rats. Of note was the wide variation in size. Internally, the same thing was true. They had the usual organs, but the proportions of each varied greatly, more than is normal. Nor were their teeth uniform. Some carried huge fangs set in delicate jaws; others had tiny teeth that didn’t match the massive bone structure. As a species, they were the most scrambled the biologist had ever encountered.
He turned the microscope on their tissues and tabulated the results. There was less difference here between individual specimens, but it was enough to set him pondering. The reproductive cells were especially baffling.
Late in the day, he felt rather than heard the soundless whoosh of the construction machinery. He looked out of the laboratory and saw smoke rolling upward. As soon as the vegetation was charred, the smoke ceased and heat waves danced into the sky.
They were building on a hill. The little creatures that crept and crawled in the brush attacked in the most vulnerable spot, the food supply. There was no brush, not a blade of grass, on the hill when the colonists finished.
* * * *
Terriers. In the past, they were the hunting dogs of the agricultural era. What they lacked in size they made up in ferocity toward rodents. They had earned their keep originally in granaries and fields, and, for a brief time, they were doing it again on colonial worlds where conditions were repeated.
The dogs the colonists brought had been terriers. They were still as fast, still with the same anti-rodent disposition, but they were no longer small. It had been a difficult job, yet Marin had done it well, for the dogs had lost none of their skill and speed in growing to the size of a great dane.
The rats moved in on the fields of fast crops. Fast crops were made to order for a colonial world. They could be planted, grown, and harvested in a matter of weeks. After four such plantings, the fertility of the soil was destroyed, but that meant nothing in the early years of a colonial planet, for land was plentiful.
The rat tide grew in the fast crops, and the dogs were loosed on the rats. They ranged through the fields, hunting. A rush, a snap of their jaws, the shake of a head, and the rat was tossed aside, its back broken. The dogs went on to the next.
Until they could not see, the dogs prowled and slaughtered. At night they came in bloody, most of it not their own, and exhausted. Marin pumped them full of antibiotics, bandaged their wounds, fed them through their veins, and shot them into sleep. In the morning he awakened them with an injection of stimulant and sent them tingling into battle.
It took the rats two days to learn they could not feed during the day. Not so numerous, they came at night. They climbed on the vines and nibbled the fruit. They gnawed growing grain and ravaged vegetables.
The next day the colonists set up lights. The dogs were with them, discouraging the few rats who were still foolish enough to forage while the sun was overhead.
An hour before dusk, Marin called the dogs in and gave them an enforced rest. He brought them out of it after dark and took them to the fields, staggering. The scent of rats revived them; they were as eager as ever, if not quite so fast.
The rats came from the surrounding meadows, not singly, or in twos and threes, as they had before; this time they came together. Squealing and rustling the grass, they moved toward the fields. It was dark, and though he could not see them, Marin could hear them. He ordered the great lights turned on in the area of the fields.
The rats stopped under the glare, milling around uneasily. The dogs quivered and whined. Marin held them back. The rats resumed their march, and Marin released the dogs.
The dogs charged in to attack, but didn’t dare brave the main mass. They picked off the stragglers and forced the rats into a tighter formation. After that the rats were virtually unassailable.
The colonists could have burned the bunched-up rats with the right equipment, but they didn’t have it and couldn’t get it for years. Even if they’d had it, the use of such equipment would endanger the crops, which they had to save if they could. It was up to the dogs.
The rat formation came to the edge of the fields, and broke. They could face a common enemy and remain united, but in the presence of food, they forgot that unity and scattered—hunger was the great divisor. The dogs leaped joyously in pursuit. They hunted down the starved rodents, one by one, and killed them as they ate.
When daylight came, the rat menace had ended.
The next week the colonists harvested and processed the food for storage and immediately planted another crop.
Marin sat in the lab and tried to analyze the situation. The colony was moving from crisis to crisis, all of them involving food. In itself, each critical situation was minor, but lumped together they could add up to failure. No matter how he looked at it, they just didn’t have the equipment they needed to colonize Glade.
The fault seemed to lie with Biological Survey; they hadn’t reported the presence of pests that were endangering the food supply. Regardless of what the exec thought about them, Survey knew their business. If they said there were no mice or rats on Glade, then there hadn’t been any—when the survey was made.
The question was: when did they come and how did they get here?
Marin sat and stared at the wall, turning over hypotheses in his mind, discarding them when they failed to make sense.
His gaze shifted from the wall to the cage of the omnivores, the squirrel-size forest creature. The most numerous animal on Glade, it was a commonplace sight to the colonists.
And yet it was a remarkable animal, more than he had realized. Plain, insignificant in appearance, it might be the most important of any animal Man had encountered on the many worlds he had settled on. The lon
ger he watched, the more Marin became convinced of it.
He sat silent, observing the creature, not daring to move. He sat until it was dark and the omnivore resumed its normal activity.
Normal? The word didn’t apply on Glade.
The interlude with the omnivore provided him with one answer. He needed another one; he thought he knew what it was, but he had to have more data, additional observations.
He set up his equipment carefully on the fringes of the settlement. There and in no other place existed the information he wanted.
He spent time in the digger, checking his original investigations. It added up to a complete picture.
When he was certain of his facts, he called on Hafner.
The executive was congenial; it was a reflection of the smoothness with which the objectives of the colony were being achieved.
“Sit down,” he said affably. “Smoke?”
The biologist sat down and took a cigarette.
“I thought you’d like to know where the mice came from,” he began.
Hafner smiled. “They don’t bother us any more.”
“I’ve also determined the origin of the rats.”
“They’re under control. We’re doing nicely.”
* * * *
On the contrary, thought Marin. He searched for the proper beginning.
“Glade has an Earth-type climate and topography,” he said. “Has had for the past twenty thousand years. Before that, about a hundred million years ago, it was also like Earth of the comparable period.”
He watched the look of polite interest settle on the executive’s face as he stated the obvious. Well, it was obvious, up to a point. The conclusions weren’t, though.
“Between a hundred million years and twenty thousand years ago, something happened to Glade,” Marin went on. “I don’t know the cause; it belongs to cosmic history and we may never find out. Anyway, whatever the cause—fluctuations in the sun, unstable equilibrium of forces within the planet, or perhaps an encounter with an interstellar dust cloud of variable density—the climate on Glade changed.
“It changed with inconceivable violence and it kept on changing. A hundred million years ago, plus or minus, there was carboniferous forest on Glade. Giant reptiles resembling dinosaurs and tiny mammals roamed through it. The first great change wiped out the dinosaurs, as it did on Earth. It didn’t wipe out the still more primitive ancestor of the omnivore, because it could adapt to changing conditions.
“Let me give you an idea how the conditions changed. For a few years a given area would be a desert; after that it would turn into a jungle. Still later a glacier would begin to form. And then the cycle would be repeated, with wild variations. All this might happen—did happen—within a span covered by the lifetime of a single omnivore. This occurred many times. For roughly a hundred million years, it was the norm of existence on Glade. This condition was hardly conducive to the preservation of fossils.”
Hafner saw the significance and was concerned. “You mean these climatic fluctuations suddenly stopped, twenty thousand years ago? Are they likely to begin again?”
“I don’t know,” confessed the biologist. “We can probably determine it if we’re interested.”
The exec nodded grimly. “We’re interested, all right.”
Maybe we are, thought the biologist. He said, “The point is that survival was difficult. Birds could and did fly to more suitable climates; quite a few of them survived. Only one species of mammals managed to come through.”
“Your facts are not straight,” observed Hafner. “There are four species, ranging in size from a squirrel to a water buffalo.”
“One species,” Marin repeated doggedly. “They’re the same. If the food supply for the largest animal increases, some of the smaller so-called species grow up. Conversely, if food becomes scarce in any category, the next generation, which apparently can be produced almost instantly, switches to a form which does have an adequate food supply.”
“The mice,” Hafner said slowly.
Marin finished the thought for him. “The mice weren’t here when we got here. They were born of the squirrel-size omnivore.”
Hafner nodded. “And the rats?”
“Born of the next larger size. After all, we’re environment, too—perhaps the harshest the beasts have yet faced.”
Hafner was a practical man, trained to administer a colony. Concepts were not his familiar ground. “Mutations, then? But I thought—”
The biologist smiled. It was thin and cracked at the edges of his mouth. “On Earth, it would be mutation. Here it is merely normal evolutionary adaptation.” He shook his head. “I never told you, but omnivores, though they could be mistaken for an animal from Earth, have no genes or chromosomes. Obviously they do have heredity, but how it is passed down, I don’t know. However it functions, it responds to external conditions far faster than anything we’ve ever encountered.”
Hafner nodded to himself. “Then we’ll never be free from pests.” He clasped and unclasped his hands. “Unless, of course, we rid the planet of all animal life.”
“Radioactive dust?” asked the biologist. “They have survived worse.”
The exec considered alternatives. “Maybe we should leave the planet and leave it to the animals.”
“Too late,” said the biologist. “They’ll be on Earth, too, and all the planets we’ve settled on.”
Hafner looked at him. The same pictures formed in his mind that Marin had thought of. Three ships had been sent to colonize Glade. One had remained with the colonists, survival insurance in case anything unforeseen happened. Two had gone back to Earth to carry the report that all was well and that more supplies were needed. They had also carried specimens from the planet.
The cages those creatures were kept in were secure. But a smaller species could get out, must already be free, inhabiting, undetected, the cargo spaces of the ships.
There was nothing they could do to intercept those ships. And once they reached Earth, would the biologists suspect? Not for a long time. First a new kind of rat would appear. A mutation could account for that. Without specific knowledge, there would be nothing to connect it with the specimens picked up from Glade.
“We have to stay,” said the biologist. “We have to study them and we can do it best here.”
He thought of the vast complex of buildings on Earth. There was too much invested to tear them down and make them verminproof. Billions of people could not be moved off the planet while the work was being done.
They were committed to Glade not as a colony, but as a gigantic laboratory. They had gained one planet and lost the equivalent of ten, perhaps more when the destructive properties of the omnivores were finally assessed.
A rasping animal cough interrupted the biologist’s thoughts. Hafner jerked his head and glanced out the window. Lips tight, he grabbed a rifle off the wall and ran out. Marin followed him.
* * * *
The exec headed toward the fields where the second fast crop was maturing. On top of a knoll, he stopped and knelt. He flipped the dial to extreme charge, aimed, and fired. It was high; he missed the animal in the field. A neat strip of smoking brown appeared in the green vegetation.
He aimed more carefully and fired again. The charge screamed out of the muzzle. It struck the animal on the forepaw. The beast leaped high in the air and fell down, dead and broiled.
They stood over the animal Hafner had killed. Except for the lack of markings, it was a good imitation of a tiger. The exec prodded it with his toe.
“We chase the rats out of the warehouse and they go to the fields,” he muttered. “We hunt them down in the fields with dogs and they breed tigers.”
“Easier than rats,” said Marin. “We can shoot tigers.” He bent down over the slain dog near which they had surprised the big cat.
The other dog came whining from the far corner of the field to which he had fled in terror. He was a courageous dog, but he could not face the great carnivore.
He whimpered and licked the face of his mate.
The biologist picked up the mangled dog and headed toward the laboratory.
“You can’t save her,” said Hafner morosely. “She’s dead.”
“But the pups aren’t. We’ll need them. The rats won’t disappear merely because tigers have showed up.”
The head drooped limply over his arm and blood seeped into his clothing as Hafner followed him up the hill.
“We’ve been here three months,” the exec said suddenly. “The dogs have been in the fields only two. And yet the tiger was mature. How do you account for something like that?”
Marin bent under the weight of the dog. Hafner never would understand his bewilderment. As a biologist, all his categories were upset. What did evolution explain? It was a history of organic life on a particular world. Beyond that world, it might not apply.
Even about himself there were many things Man didn’t know, dark patches in his knowledge which theory simply had to pass over. About other creatures, his ignorance was sometimes limitless.
Birth was simple; it occurred on countless planets. Meek grazing creatures, fierce carnivores—the most unlikely animals gave birth to their young. It happened all the time. And the young grew up, became mature and mated.
He remembered that evening in the laboratory. It was accidental—what if he had been elsewhere and not witnessed it? They would not know what little they did.
He explained it carefully to Hafner. “If the survival factor is high and there’s a great disparity in size, the young need not ever be young. They may be born as fully functioning adults!”
* * * *
Although not at the rate it had initially set, the colony progressed. The fast crops were slowed down and a more diversified selection was planted. New buildings were constructed and the supplies that were stored in them were spread out thin, for easy inspection.
The pups survived and within a year shot up to maturity. After proper training, they were released to the fields where they joined the older dogs. The battle against the rats went on; they were held in check, though the damage they caused was considerable.
The Eleventh Golden Age of Science Fiction Megapack Page 24
