The World of Ptavvs by Larry Niven

doing the same thing with dolphins for years, but it never affected you this way. What's the matter with you, Greenberg? Snap out of it!"
    The slave in the travel chair made no move to kill himself. "You," Kzanol/Greenberg paused to translate, "whitefood. You despicable, decaying, crippled whitefood with defective sex organs. Stop telling me who I am! I know who I am!" He looked down at his hands. Tears formed at the corners of his eyes and ran itching down his cheeks, but his face remained as expressionless as a moron's. Garner blinked at him. "You think you are what's-his-name, the alien terror from Outer Space? Nuts. The alien terror is down on the first floor of this building, and he's perfectly harmless. If we could get him back to normal time he would be the first to call you an impostor. Later I'll take you down and show him to you.
    "Part of what you said is true. I am, of course, an old man. But what is a, er, whitefood?" He made the word a separate question.
    Kzanol had calmed down. "I translated. The whitefood is an artificial animal, created by the tnuctipun as a meat animal. A whitefood is as big as a dinosaur and as smooth and white as a shmoo. They're a lot like shmoos. We can use all of their bodies, except the skeleton, and they eat free food, which is almost as cheap as air. Their shape is like a caterpillar reaching for a leaf. The mouth is at the front of the belly foot."
    "Free food?"
    Kzanol/Greenberg didn't hear him. "That's funny. Garner, do you remember the pictures of bandersnatchi that the second Jinx expedition sent back? Greenberg was going to read a bandersnatch mind someday."
    "Sure. Hey!"
    "Bandersnatchi are whitefoods," said Kzanol/Greenberg. "They don't have minds."
    "I guessed that. But, son, you've got to remember that they've had two billion years to develop minds."
    "It wouldn't help them. They can't mutate. They were designed that way. A whitefood is one big cell, with a chromosome as long as your arm and as thick as your little finger. Radiation could never affect them, and the first thing that would be harmed by any injury would be the budding apparatus." Kzanol/Greenberg was bewildered. What price another coincidence? "Why would anyone think they were intelligent?"
    "Well, for one thing," Garner said mildly, "the report said the brain was tremendous. Weighed as much as a three-year-old boy."
    Kzanol/Greenberg laughed. "They were designed for that, too. The brain of a whitefood has a wonderful flavor, so the tnuctip engineers increased its size. So?"
    "So it's convoluted like a human brain."
    Why, so it was. Like a human brain, and a tnuctip brain, and a thrint brain, for that matter. Now why--
    Kzanol/Greenberg cracked his knuckles, then hurriedly separated his hands so that he couldn't do it again. The mystery of the intelligent "bandersnatch" bothered him, but he had other things to worry about. Why, for example, hadn't he been rescued? Three hundred years after he pushed the panic button, he must have struck the Earth like the destroying wrath of the Powergiver. Someone on the moon must have seen it.
    Could the lunar observation post have been abandoned?
    Why?
    Garner crashed into his thoughts. "Maybe something bigger than a cosmic ray made the mutations. Something like a machine-gun volley or a meteor storm."
    Kzanol/Greenberg shook his head. "Any other evidence?"
    "Oh, hell yes. Greenberg, what do you know about Jinx?"
    "A good deal," said Kzanol/Greenberg. Larry's knowledge of Jinx had been as thorough as any colonist's. The memories clicked into place, unbidden, at the sound of the word. Jinx.
    Moon of Binary, third planet out from Sirius A. Binary was a banded orange giant, bigger than Jupiter, and much warmer. Jinx was six times as big as Earth, with a gravity of one point seven eight, and with a period of rotation more than four days long. Of all the factors which had shaped Jinx, the most important had been its lack of radioactive materials. For Jinx was solid all through