“Y-yes.”
“Native Atheian biochemistry developed’in a manner quite parallel to Earth’s,” said the voice, “and the early colonists had no difficulty in introducing terrestrial species. Thus they enjoyed a friendly environment, where population soon grew sufficiently large to obviate the danger of racial change through mutation and/or genetic drift. In addition, no selection pressure tended to force change. Hence the modern Atheian human is little different from his ancestors of Earth, on which account his physiology and biochemistry are known in detail.
“This has been essentially the case on most colonized planets for which records are available. Where different breeds of men have arisen, it has generally been because the original settlers were highly selected groups. Randomness, and evolutionary adaptation to new conditions, have seldom produced radical changes in biotype. For example, the robustness of the average Krakener is a response to comparatively high gravity; his size aids him in resisting cold, his fair complexion is helpful beneath a sun poor in ultraviolet… But his ancestors were people who already had the natural endowments for such a world. His deviations from their norm are not extreme. They do not preclude his living on more Earth-like planets or interbreeding with the inhabitants of these.
“Occasionally, however, larger variations have occurred. They appear to be due to a small original population or to unterrestroid conditions or both. The population may have been small because the planet could not support more or have become small as the result of hostile action when the Empire fell. In the former case, genetic accidents had a chance to be significant; in the latter, radiation produced a high rate of mutant births among survivors. The variations are less apt to be in gross anatomy than in subtle endocrine and enzymatic qualities, which affect the physiology and pyschology. Well known cases include the reaction of the Gwydiona to nicotine and certain indoles, and the requirement of the Ifrians for trace amounts of lead. Sometimes the inhabitants of two planets are actually intersterile because of their differences.
“While this world has hitherto received the sketchiest of examinations—” Evalyth was yanked out of a reverie into which the lecture had led her “—certain facts are clear. Few terrestrial species have flourished; no doubt others were introduced originally, but died off after the technology to maintain them was lost. Man has thus been forced to depend on autochthonous life for the major part of his food. This life is deficient in various elements of human nutrition. For example, the only Vitamin C appears to be in immigrant plants; Sairn observed that the people consume large amounts of grass and leaves from those species, and that fluoroscopic pictures indicate this practice has measurably modified the digestive tract. No one would supply skin, blood, sputum, or similar samples, not even from corpses.”
“The calculations are now complete.” As the computer resumed, Evalyth gripped the arms of her chair and could not breathe. “While the answer is subject to fair probability of success. In effect, Atheian flesh is alien here. It can be metabolized, but the body of the local consumer will excrete certain compounds, and these will import a characteristic odor to skin and breath as well as to urine and feces. The chance is good that it will be detectable by neo-Freeholder technique at distances of several kilometers, after sixty or seventy hours. But since the molecules in question are steadily being degraded and dissipated, speed of action is recommended.”
“Shall the organisms be ordered for you and given the appropriate search program?” asked the voice. “They can be on hand in an estimated three hours.”
“Yes,” she stammered. “Oh, please—Have you any other… other… advice?”
“The man ought not to be killed out of hand, but brought here for examination, if for no other reason than in order that the scientific ends of the expedition may be served.”
The single big moon rose nearly full, shortly after sundown. It drowned most stars; the jungle beneath was cobbled with silver and, dappled with black; the snow-cone of Mount Burus floated unreal at the unseen edge of the world. Wind slid around Evalyth where she crouched on her graysled; it was full of wet acrid, odors, and felt cold. though it was not, and chuckled at her back. Somewhere something screeched, every few minutes; and something else cawed reply.
She scowled at her position indicators, aglow on the control panel. Curses and chaos, Moru had to be in this area! He could not have escaped from the valley on foot in the time available, and her search pattern had practically covered it. If she ran out of bugs before she found him, must she assume he was dead? They ought to be able to find his body regardless, ought they not? Unless it was buried deep. Here. She brought the sled over to hover, took the next phial off the rack and stood up to open it.
The bugs came out many and tiny, like smoke in the moonlight. Another failure?
No! Wait! Were not those motes dancing back together, into a streak barely visible under the moon, and vanishing downward? Heart thuttering, she turned to the indicator. Its neurodetector antenna was not aimlessly wobbling, but pointed straight west-northwest, declination thirty-two degrees below horizontal. Only a concentration of the bugs could make it behave like that. And only the particular mixture of molecules to which ‘ the bugs had been presensitized, in several parts per million or better, would make them converge on the source.
“Ya-a-ah!” She couldn’t help the one hawk-yell. But thereafter she bit her lips shut—blood trickled unnoticed down her chin—and drove the sled in silence.
The distance was a mere few kilometers. She came to a halt above an opening in the forest. Pools of scummy water gleamed in its rank growth. The trees made a solid-seeming wall around. Evalyth clapped her night goggles down off her helmet and over her eyes. A lean-to became visible. It was hastily woven from vines and withes, huddled against a part of the largest trees to let their branches hide it from the sky. The bugs were entering.
Evalyth lowered her sled to a meter off the ground and got to her feet again. A stun pistol slid from its sheath into her right hand. Her left rested on the blaster.
Moru’s two sons groped from the shelter. The bugs whirled around them, a mist that blurred their outlines.
The parents followed them, ignored by the entranced bugs. The mother wailed. Evalyth identified a few words. “What is the matter, what are those things—oh, help—” But her gaze was locked upon Moru.
Limping out of the hutch, stooped to clear its entrance, he made her think of some huge beetle crawling from an offal heap. But she would know that bushy head though her brain were coming apart. He carried a stone blade, surely the one that had hacked up Donli.
The wife’s scream broke through. She had seen the metal thing, and the giant that stood on its platform, with skull and eyes shimmering beneath the moon.
“I have come for you who killed my man,” Evalyth said.
The mother screamed anew and cast herself before the boys. The father tried to run around in front of her, but his lame foot twisted under him, and he fell into a pool. As he struggled out of its muck, Evalyth shot the woman. No sound was heard; she folded and lay moveless. “Run!” Moru shouted. He tried to charge the sled. Evalyth twisted a control stick. Her vehicle whipped in a circle, heading off the boys. She shot them from above, where Moru couldn’t quite reach her.
He knelt beside the nearest, took the body in his arms and looked upward. The moonlight poured relentlessly across him. “What can you now do to me?” he called.
She stunned him too, landed, got off and quickly hog-tied the four of them. Loading them aboard, she found them lighter than she had expected.
Sweat had sprung forth upon her, until her coverall stuck dripping to her skin. She began to shake, as if with fever. Her ears buzzed. “I would have destroyed you,” she said. Her voice sounded remote and unfamiliar. A still more distant part wondered why she bothered speaking to the unconscious, in her own tongue at that. “I wish you