Isaac Asimov - Foundation and Earth

And if human beings somehow vanished, then other predators must take their place. But what predators? The most sizable predators tolerated by human beings were dogs and cats, tamed and living on human bounty.

What if no human beings remained to feed them? They must then find their own food—for their survival and, in all truth, for the survival of those they preyed on, whose numbers had to be kept in check lest overpopulation do a hundred times the damage that predations would do.

So dogs would multiply, in their variations, with the large ones attacking the large, untended herbivores; the smaller ones preying on birds and rodents. Cats would prey by night as dogs did by day; the former singly, the latter in packs.

And perhaps evolution would eventually produce more varieties, to fill additional environmental niches. Would some dogs eventually develop sea-going characteristics to enable them to live on fish; and would some cats develop gliding abilities to hunt the clumsier birds in the air as well as on the ground?

In flashes, all this came to Trevize while he struggled with more systematic thought to tell him what he might do.

The number of dogs kept growing. He counted twenty-three now surrounding the tree and there were others approaching. How large was the pack? What did it matter? It was large enough already.

He withdrew his blaster from its holster, but the solid feel of the butt in his hand did not give him the sense of security he would have liked. When had he last inserted an energy unit into it and how many charges could he fire? Surely not twenty-three.

What about Pelorat and Bliss? If they emerged, would the dogs turn on them? Were they safe even if they did not emerge? If the dogs sensed the presence of two human beings inside the ruins, what could stop them from attacking them there? Surely there would be no doors or barriers to hold them off.

Could Bliss stop them, and even drive them away? Could she concentrate her powers through hyperspace to the desired pitch of intensity? For how long could she maintain them?

Should he call for help then? Would they come running if he yelled, and would the dogs flee under Bliss’s glare? (Would it take a glare or was it simply a mental action undetectable to onlookers without the ability?) Or, if they appeared, would they then be torn apart under the eyes of Trevize, who would be forced to watch, helplessly, from the relative safety of his post in the tree?

No, he would have to use his blaster. If he could kill one dog and frighten them off for just a while, he could scramble down the tree, yell for Pelorat and Bliss, kill a second dog if they showed signs of returning, and all three could then hustle into the ship.

He adjusted the intensity of the microwave beam to the three-quarter mark. That should be ample to kill a dog with a loud report. The report would serve to frighten the dogs away, and he would be conserving energy.

He aimed carefully at a dog in the middle of the pack, one who seemed (in Trevize’s own imagination, at least) to exude a greater malignancy than the rest—perhaps only because he sat more quietly and, therefore, seemed more cold-bloodedly intent on his prey. The dog was staring directly at the weapon now, as though it scorned the worst Trevize could do.

It occurred to Trevize that he had never himself fired a blaster at a human being, or seen anyone else do it. There had been firing at water-filled dummies of leather and plastic during training; with the water almost instantaneously heated to the boiling point, and shredding the covering as it exploded.

But who, in the absence of war, would fire at a human being? And what human being would withstand a blaster and force its use? Only here, on a world made pathological by the disappearance of human beings—

With that odd ability of the brain to note something utterly beside the point, Trevize was aware of the fact that a cloud had hidden the sun—and then he fired.

There was an odd shimmer of the atmosphere on a straight line from the muzzle of the blaster to the dog; a vague sparkle that might have gone unnoticed if the sun were still shining unhindered.

The dog must have felt the initial surge of heat, and made the smallest motion as though it were about to leap. And then it exploded, as a portion of its blood and cellular contents vaporized.

The explosion made a disappointingly small noise, for the dog’s integument was simply not as tough as that of the dummies they had practiced on. Flesh, skin, blood, and bone were scattered, however, and Trevize felt his stomach heave.

The dogs started back, some having been bombarded with uncomfortably warm fragments. That was only a momentary hesitation, however. They crowded against each other suddenly, in order to eat what had been provided. Trevize felt his sickness increase. He was not frightening them; he was feeding them. At that rate, they would never leave. In fact, the smell of fresh blood and warm meat would attract still more dogs, and perhaps other smaller predators as well.

A voice called out, “Trevize. What—”

Trevize looked outward. Bliss and Pelorat had emerged from the ruins. Bliss had stopped short, her arms thrown out to keep Pelorat back. She stared at the dogs. The situation was obvious and clear. She had to ask nothing.

Trevize shouted, “I tried to drive them off without involving you and Janov. Can you hold them off?”

“Barely,” said Bliss, not shouting, so that Trevize had trouble hearing her even though the dogs’ snarling had quieted as though a soothing sound-absorbent blanket had been thrown over them.

Bliss said, “There are too many of them, and I am not familiar with their pattern of neuronic activity. We have no such savage things on Gaia.”

“Or on Terminus. Or on any civilized world,” shouted Trevize. “I’ll shoot as many of them as I can and you try to handle the rest. A smaller number will give you less trouble.”

“No, Trevize. Shooting them will just attract others. —Stay behind me, Pel. There’s no way you can protect me. —Trevize, your other weapon.”

“The neuronic whip?”

“Yes. That produces pain. Low power. Low power!”

“Are you afraid of hurting them?” called out Trevize in anger. “Is this a time to consider the sacredness of life?”

“I’m considering Pel’s. Also mine. Do as I say. Low power, and shoot at one of the dogs. I can’t hold them much longer.”

The dogs had drifted away from the tree and had surrounded Bliss and Pelorat, who stood with their backs to a crumbling wall. The dogs nearest the two made hesitant attempts to come closer still, whining a bit as though trying to puzzle out what it was that held them off when they could sense nothing that would do it. Some tried uselessly to scramble up the wall and attack from behind.

Trevize’s hand was trembling as he adjusted the neuronic whip to low power. The neuronic whip used much less energy than the blaster did, and a single power-cartridge could produce hundreds of whip-like strokes but, come to think of it, he didn’t remember when he had last charged this weapon, either.

It was not so important to aim the whip. Since conserving energy was not as critical, he could use it in a sweep across the mass of dogs. That was the traditional method of controlling crowds that showed signs of turning dangerous.

However, he followed Bliss’s suggestion. He aimed at one dog and fired. The dog fell over, its legs twitching. It emitted loud, high-pitched squeals.

The other dogs backed away from the stricken beast, ears flattening backward against their heads. Then, squealing in their turn, they turned and left, at first slowly, then more rapidly, and finally, at a full race. The dog who had been hit, scrambled painfully to its legs, and limped away whimpering, much the last of them.