Bram, stiff and aching, turned back to the visual display where a mini-ecology was suspended, waiting for him to animate it again.
He could only guess at the scale; a few simple multi-celled organisms wriggled through greenish water, but one of the swimmers — though its organization was complex enough to provide a whiplike tail and an unarguable gullet — was obviously single-celled. Bram could easily see the shadow of a cell nucleus and several organelles within the translucent form.
The frame of the picture jerked, and the magnification changed. Bram gasped at the teeming life he saw there. A segmented creature with long feelers darted past at close range. A flattened ribbon with a deltoid head and eyespots undulated through feathery green bottom plants. There was something like a tube or sac with a cluster of waving tentacles at one end, much like some of the small aquatic forms here on the Father World. There must have been, Bram realized with wonder, at least fifteen or twenty separate varieties of plants and animals represented in the picture.
There was a puzzle here. The creatures didn’t exist. Or at least, if they once had existed, they were no longer being manufactured. They had no obvious utility, of course. Were they steps on the road to man? It seemed unlikely. Not all of them, surely.
The senders of that stupendous genetic message from the dim past had necessarily been parsimonious. It took a thousand genes or more to specify the enzymes for a single cell, such as a simple soil bacterium. To construct a human being, one needed more than a hundred thousand genes adding up to well over a billion nucleotides; Bram had seen the cupboards where copies of those magnetic storage records were kept, and they contained more shelf space than the cabinets for all the cultural records combined.
Potatoes were simpler than people, of course. The limited selection of food plants needed to support reconstructed man, the necessary microorganisms, the handful of useful life forms like the poplar tree — none of them had required anywhere near as much transmission time. And additional variations, even new species, could be derived from short nucleotide inserts and from protoplast-derived clones that were somatic variants. But it all added up in terms of transmission priorities.
So there didn’t seem to be much point in making an aquarium like the one Bram saw before him.
Perhaps only visual footage had been transmitted. Maybe the aquarium had existed on man’s world. Even so, it seemed profligate. It had been running for some minutes. How many thousands of color frames had been lavished on this presentation? The art historians would have given their eyeteeth for a fraction of this precious time.
Bram rotated his forearms slightly, trying to pick up additional clues. The prickly sensations continued; they constituted a running commentary on what he was seeing. And they contained the same overtones of dread that he had detected on the whole-body reader.
And something else.
This section of the record came from the codicil he had imprudently mentioned to Kerthin — the supplement that had added fourteen years of transmission time the second time around, before the message had been cut off. So whatever genetic information was contained in this electronic bin could not have been needed to draw up the blueprint of man.
It was an afterthought.
An afterthought somehow connected with the idea of heterochronic genes and with man himself.
The sense of dread built. Bram’s trembling arms strained to hold their position. On the screen he watched a scuttling multilegged creature whose resemblance to man was poignant.
Discount the armor-plated body, the segmented legs, the feelers it waved ahead of itself as it climbed a green blade. It possessed bilateral symmetry, paired eyes in a sort of face, and, obviously, some sort of central nerve pathway instead of a neural net.
More to the point, it possessed the same sort of DNA as did Bram himself, not the Father World’s sort with its uracil-adenine pairs and reversed sugars. Bram could not take his eyes off it. He realized that tears were running down his face.
And then the water exploded into motion.
A nightmare creature filled the screen, all head and hairy legs, with a long slender body trailing behind. Its eyes were like green tomatoes, its mouth a vertical cleft. The armored creature was gone, simply vanished. Bram had just time enough to glimpse a twitching leg disappearing into that strange maw, and then the two hemispheres of the face snapped shut again.
An afterimage lingered in Bram’s vision. He could not be sure he had really seen it, but there was the impression of something long and scooplike that had whipped out of that bisected face and drawn the segmented creature inside.
Bram blinked again, and now the monster itself was gone, flicking itself away by some process too fast to follow.
His fingers scrabbled for the touch pad, trying to bring the picture back so that he could study it one frame at a time. But the machine misunderstood his human input. Somehow he had triggered a search program. He could feel the successive ridges of raised pinpricks marching across his joined arms, the forward edge of a great arc of rotating wheel. Random images flashed across the screen. But try as he might, he could not call up the sequence he had just seen.
He was back on the fringes of the heterochronic egg project, following one branch after another — decades, perhaps centuries, of diverging data. None of it told him how the long codicil was supposed to be connected with the genetic program for man — a program that already had been complete in itself. What kind of synthetic gene, destined for man, was supposed to come out of these tomato-eyed horrors? Bram shuddered.
He tried for the next couple of hours to backwind the search program to the point he wanted. He got back to the assembly of the early terrestrial protocells without any problems, but then the database began skipping all over the place. When daylight began to show through the window, he gathered up the holo printouts he had generated, cleaned up, and went back to his own cubbyhole and sat down at his desk.
He was still sitting there when the orthocone awakened to morning life. The elevators hummed, daylight flooded through the oval ports and washed out the bioglow, and the resonant thrum of Nar voices spread through the passages. A pair of co-workers came in, holding hands in conversation — early arrivals from the proteins assembly subgroup. They saw Bram sitting at his desk and, after a twitch of surprise, saluted him with a flared tentacle apiece.
“Greeting, Bram-brother. You are at work early this morning.”
Voth came drifting in about midmorning, large and imposing with hydrostatic pressure. He was gaining actual mass as well, with his increased appetite these days. He gave a preoccupied top flutter to the juniors in the atrium and sailed past them to his office, moving in the absent-minded spiral gait of five-way equipoise.
Bram gave him a few minutes to get settled, then followed him inside. Kerthin would have seventeen fits at what he was about to do, but he could not leave the matter as it now stood.
It went against his grain to behave conspiratorially, as Kerthin wanted him to do. He could not bring himself to believe that there was anything sinister in Nar motives. If anything, the Nar were paternalistic and overprotective toward their human wards. Bram had never known anything but affection from Voth and his touch brothers.
He didn’t care if Voth knew that he had dipped into forbidden knowledge — if it was forbidden. The only thing that bothered him was that he could not now be totally forthright with Voth. It would have been too embarrassing to admit that he had succumbed to Kerthin’s suspicions — that he had gone sneaking about in the middle of the night.
But he could be oblique.
“You’re tired, Bram,” Voth said, turning a couple of eyes on him. “It is not good to stay awake nights.”
Bram gave a guilty start, then realized that Voth merely had interpreted correctly his bloodshot eyes and stiff movements. Voth, even for a member of a naturally empathetic species like the Nar, was a superb reader of the human body.
“I’m all right,” Bram said.
Voth, noti
cing his hesitation, beckoned inwardly with his crown if tentacles. “Don’t hang about by the door, youngling. Come over here.”
Bram perched beside Voth and let him wrap a tentacle around his bare forearm. It was the only comfortable way for a Nar to talk, even in the Small Language. Bram needed the contact almost as much; it was how he had been raised.
“Now, tell me what is troubling you,” the decapod said before Bram could speak.
“There is a thing I do not understand,” Bram said.
Hesitantly at first, then with increasing fluency, he let his doubts pour out. He summarized his problems in retracing the origins of the heterochronic genes, told of his encounter with the warning bells in the file from the codicil and the elusive footage of the voracious underwater monster. He left out the circumstances under which he had run across it and hoped that his blush would not betray him.
“What was it, Voth?” he concluded lamely.
The old decapod was silent for several seconds. The wrapped tentacle gave a little squeeze, as if Voth were trying to hold onto him more tightly. It recalled for Bram the way, when he was a small child, that Voth had restrained him in the presence of moving machinery or dangerous heights.
“I am surprised at your interest,” Voth said finally. “Those archives have been untouched for centuries. I had almost forgotten that they exist.”
“It was a terrestrial life form, wasn’t it?” Bram prompted. “It had six legs. But they were paired.”
Voth sighed: a rush of wind and a relaxation of muscle. “It is called a nymph.”
The word, as Voth pronounced it, had an Inglex ring to it. After a moment, Bram remembered. It came from the translation of Homer. A nymph had held Odysseus prisoner in a cave.
“It is a stage in the development of a particular terrestrial life form,” Voth went on, as if the words were painful. “The adult form is quite different — an air breather with wings. It lives for only a brief mating season. But the immature nymph form may persist for two or three years. It is one of the most dangerous creatures in its particular ecological niche. It exists only to eat other life forms — some of them as large as itself. Swimmers, crawlers, even small manlike amphibians.” Voth broke off, as if the subject were distasteful.
“What was the adult form called?” Bram asked.
“A dragonfly.”
Bram knew about dragons. He shivered. The adult form must have been a fearsome creature indeed.
“Why … why would the message senders have expended data time on such an organism?”
“As a warning.”
“Warning?” So the source of all those danger flags had been Original Man himself. The Nar records would have amplified them, adapted them for Nar sensibilities, and spread them through the associated data frames.
“A warning to whomever might have received the first cycle of the message.”
“It was in the codicil, then?”
“Yes.” A fountaining wave front of cilia movement showed that Voth was uncomfortable with the subject. “The dragonfly genetic information — not complete, fortunately — had been sent earlier as part of a particular genetic exposition. Fifty years later, they had
Handle with care. That was the meaning of the warning flags that had kept Bram at arm’s length from the data.
“May I know the nature of this genetic exposition, Voth-shr-voth?” Bram asked formally.
“Of course.” Voth’s fibrillar membranes dilated contritely. “When have I kept anything from you, even as a child? You are entitled to the information available to any junior of good sense and judgment.”
The juniors in the department were at least a couple of centuries old. The implicit meaning of what Voth had just said was best passed over, and he went on quickly.
“The dragonfly was one of a number of earthly life forms with extended immature stages. Only the imago — the adult form — reproduced. The humans conducted experiments to modify the cellular timing mechanism, to see if sexual maturity could be induced in the aquatic form.”
“Heterochronic genes,” Bram said, beginning to understand.
“Their purpose was to make the arctic regions of their home planet more habitable. A modified nymph, they thought, would control small biting insects called blackflies and mosquitoes that still inhibited full exploitation of these regions, even at the height of man’s technological prowess. Such organisms, it seems, were also water-breeding. And the nymph devoured anything that swam.”
Voth’s sensitive tentacle lining fluttered in a manner that in a human being would have been called a shudder.
Bram could empathize with Voth’s instinctive revulsion. Voth was visualizing the tiny swimmers that would be his own children, after he had expended his life in mating — and imagining a creature like a dragonfly nymph gobbling them up.
“The key to a synthetic heterochronic gene was found in a peculiar creature called an axolotl,” Voth went on. “The axolotl was the larval form of a kind of animal known to humans as a salamander. But unlike other salamanders, the axolotl spent its entire life as a larva. It was able to reproduce without undergoing metamorphosis to its adult stage. It retained its gills and lived and died as an aquatic form. Human scientists believed it to be a separate species until, by chance, some axolotls on exhibition changed into air-breathing adults, as axolotls cut off from water will sometimes do.”
Bram furrowed his brow. “The heterochronic mutation would have to be a dominant one. But if it could be turned off, it means —”
“Dominant heterochronic mutations cause particular cell lines to repeat immature patterns instead of developing. Recessive heterochronic mutations, on the other hand, cause premature development of other cell lines.”
“Yes, I see. Axolotls were a sexually mature larval form. So when those exhibit specimens completed their metamorphosis, something had happened to turn off the dominant mutant genes that had prevented cell differentiation in those cell lines not concerned with reproduction, though leaving the reproductive system itself to mature normally. But dragonfly nymphs were sexually immature. So somehow the mechanisms of a recessive heterochronic mutation would have to be mimicked in order to turn on the genes for sexual maturity. While at the same time acting as a dominant mutation to suppress adult development of nonreproductive cell lines.”
Voth gave a confirming squeeze to Bram’s arm. “Precisely. A set of synthetic chimeras was contrived by man and spliced into a dragonfly sequence. The container and the contents were inseparable, unfortunately. Further species-crossing capability had to be determined by trial and error. That merged set of genes was the one we were given to work with. By the time of the warning in man’s codicil, we were already well along with our work on the heterochronic hen’s egg.”
“Why was a warning necessary?”
“An unstable allele was found at a key junction. It made the gene vulnerable to point mutation caused by random radiation. A chemical regulator related to thyroglobulin was no longer suppressed. And, like the captive axolotls, the mutated nymphs lost their gills.”
“They became air breathers,” Bram said grimly.
Voth’s organ voice carded wheezing overtones of stress. “The result was an organism that got out of control, spilling out of the ecological niche for which it had been intended. The ground-dwelling nymphs were large and active. Formidable enough to prey on small mammals called rodents. Vicious enough to attack even larger mammals, including man. They were a greater danger than the blackflies and mosquitoes they had been intended to control. They were exterminated with great difficulty. It took decades. And when it was over, whole regions of the arctic were so poisoned as to be economically useless.”
Bram thought of the footage he had seen. Voth had avoided being explicit about its origin. “Was the nymph recreated here on the Father World?” he asked.
Voth gave a shuddery fibrillation. “No. It was an incomple
te genome, fortunately. It might have been possible to construct a close analog by filling in the gaps. There were some who actually wanted to do such a thing. They argued that even if the creature were to escape from the laboratory, it could not have survived, because it would have been poisoned by the proteins of our life forms.”
Bram felt the hairs on the back of his neck rise, in the human analog of Voth’s reaction. “There are single-celled planticules here on the Father World that produce terrestrial-style right-hand amino acids,” he said. “There are other organisms that have evolved to metabolize all sorts of poisonous substances into simple abiotic organic compounds. There are higher life forms that live in symbiosis with colonies of protozoans within their digestive organs and are nourished by the breakdown products. Even we humans utilize some Nar food sources by using them as feedstocks for industrial microorganisms.” His voice dropped to a whisper. “If a creature like the nymph ever learned how to use the native-style proteins and amino acids and then somehow got out of the laboratory …”
“That was exactly the argument of those who opposed the creation of a nymphlike construct, myself included,” Voth said. “There was already too much terrestrial DNA around, particularly in the tailored microorganisms associated with our infant cellulose industry. If there was even the most astronomically remote possibility that some mutated form might colonize the nymphs and act as a metabolic buffer for them, then we dared not risk it.”
“No,” Bram agreed fervently. “You couldn’t.”
“We held an all-world touch conclave to consider the matter. We waited two years for Juxt One’s touch transcription, even longer for the farther stars. No world or moon that had even a few thousand Nar living on it was left out. The vote was close. But the touch union makes us all one in questions affecting the entire race, so the decision was thereafter binding on all Nar.”
The Genesis Quest Page 13