Читать книгу The Face of Heaven - Brian Stableford - Страница 14

Chapter 10

The Underworld did not, of course, begin all at once. The eclipse of the old surface by the new was a gradual affair, taking several thousands of years. What is more, the platform which was to become the Overworld was started in several sections. Thus the perimetric borderlines between the two worlds were both extensive and slow-moving.

Gradually, the life-system of Earth moved across those borders. Under each section of the covered world some kind of ecosystem survived from the ancient world. The surface was already spoiled and communities of organisms had been in a state of dynamic imbalance for some time before the light of the sun was gradually cut out. The extra pressure imposed by the theft of the sun was great, but not ultimately decisive. When the sections of the platform joined up, so did the two struggling—and not necessarily similar—communities which had grown beneath them. The comingling of the communities induced competition and complementation, and assisted the evolutionary adaptation of the new whole.

Homo sapiens was the species which adapted most easily to the new régime, and by his active interference he encouraged and assisted many other species to do likewise. Not all men belonged to Euchronia. Some preferred their own concept of freedom: freedom from a plan which would demand their total commitment and pay them—individually speaking—absolutely nothing. There were a good many men who regarded the New World as a dream—castles in the air—and who thought it both right and wise to commit themselves to the Old World, and to dedicate themselves to making what they could of it.

Despite a certain amount of mutual dislike and resentment, a good deal of trade went on between the Euchronians and the Groundmen for many centuries while the platform was under construction. Without the food supplies, and to a lesser extent the mineral supplies provided by the men who were committed to the ground, the early years would have been far more difficult for the Planners. But as the platform grew, it grew over the lands which were used by the Groundmen—and it swallowed up the lands of the cooperative just as it swallowed up the lands of the hostile. For many centuries there was a bitter war fought on the expanding frontiers of the Overworld. The Men of the Old World thought they had dealt fairly with Euchronia, and that the theft of their sun was the harshest of evil treatment. The Euchronians believed that the Plan was all-important, that there could be no compromises, and they offered the only compensation they had to offer to all those on the ground—the opportunity to join the Plan. Most of the Groundmen refused, and most of them migrated before the advancing world of darkness, until there was nowhere else left to run, except to the islands which were too tiny to interest the Planners. Many of the islands were already incapable of sustaining human life—there was a poor living to be made from the desolated sea—and many more became so as the hordes descended on their shores. Some island colonies were successful, but for the vast majority of men there were only two choices which mattered: Heaven and Hell. When the platform finally closed its grip on the world, the larger number capitulated, and ascended to Heaven and commitment to the Plan (which was still millennia away from completion). A substantial number, however—perhaps a surprising number—stayed with the Old World, accepting the pale electric stars as a permanent substitute for the garish sun. Their motives were many, and usually mixed. Bitterness and sheer hatred for the Planners were prominent, but not paramount. The dominant reason for the human race refusing to quit the Old World was a commitment to it and an identification with it that was as powerful as the commitment of Euchronia to its Plan.

The Old World was past redemption in terms of the human civilization which had grown up in it. But that did not mean that life was doomed to extinction, nor even that there was any realistic possibility that life would become extinct. It merely meant that most of the old species had to die, and that hitherto unimportant species would become vital to the system, and also that new species would have to be discovered. A whole new contract for the interaction of life with environment had to be drawn up and negotiated—negotiated largely (but not entirely, thanks to the presence of man) by trial and error.

The lowest stratum of the biotic hierarchy, the stratum of primary production, underwent the greatest changes. The priority enjoyed by photosynthetic forms was lost. Plant evolution virtually abandoned the angiosperms and reverted to a more primitive state in order to rebuild. The stars were vital in that they allowed the bridge a small extra margin, but in the end they were quite useless as sources of energy (save to a few fugitive species of little importance). Their only real function was to provide for the senses of much higher organisms—man, in particular.

Obviously, it was the fungi and the nonphotosynthetic algae which proved most readily adaptable to the new conditions. They underwent an evolutionary renaissance with great alacrity.

The specialists of the second stratum—the primary consumers—went the way of their diet. The generalists, however, simply reordered their personal priorities. Man had no chance at all of saving the cow, the sheep, or the hen, but he could and did save the pig.

In the higher strata, the percentage devastation decreased serially. Secondary consumers tended to be much less particular than primaries, and had an advantage because of the relative success of some primary species. The more secondaries that were successful, the easier it became for the tertiaries. There was change in the higher regions of life’s hierarchy—of course there was change—but there was a relatively low level of extinction. In terms of appearance, change was slow but eventually drastic, but in terms of evolutionary continuity there was nothing like the cataclysmic reorganization suffered in the lower strata. Only the specialist insectivores and some of the carnivores disappeared from the scene that was visible to the naked eye. Microbiotically, things were slightly more complicated, but the principle remained the same.

The omnivores were in no real trouble (in terms of racial survival) at any time. Any species which had survived the rigors of the second dark age was unlikely to be troubled by the roofing of the world. Man’s ancient allies the cat and the dog both survived—but independently of man. His ancient rivals, the rat and the cockroach, also survived—indeed, they thrived.

Extinction was responsible for very few of the changes which took place in the tertiary strata. Adaptation, on the other hand, demanded that vast changes in behavioral patterns—and often vast changes in physical form—must take place.

Under the circumstances of such a vast reorganization evolution was permitted—forced, in fact—to work very quickly indeed. The rate of evolution, not just in one or a group of species but throughout the life-system, passed into tachytelic mode.

Evolution by natural selection can be immensely costly. In order to replace erstwhile-useful genes by now-useful genes, vast numbers of individuals in a number of generations have to die. The load on the species becomes tremendous. This demands great fecundity and the acceptance of a very high mortality rate. When unusual requirements are placed on a species the gross numbers of that species inevitably shrink. The more the numbers shrink the faster the turnover of genes proceeds. But there is a threshold beyond which the species cannot replenish itself no matter how fast its rate of evolution. At or near that threshold the evolutionary process is capable of incredible bursts of change. Below it, extinction becomes inevitable and the species dies amid a truly frantic burst of adaptive attempts. If, however, the evolutionary burst at threshold is successful in providing a whole new schema of adaptation without taking the absolute numbers of the standing population too low, the evolutionary burst is followed by a rapid increase in numbers, during which selection still continues to foster a rate of evolution faster than the “normal” horotelic mode characteristic of a stable species in a stable environment. Relatively rare species with a high degree of genetic homogeneity existing in ultra-stable environments may slip into the third mode of evolutionary pace—the bradytelic—whereby change slows down drastically and the species retains little capacity for change.

During the thousands of years that the Euchronians were taking their Plan to ultimate completion the tachytelic evolution which embraced the entire Underworld life-system completely changed the face of the lower Earth. A few thousand years is a very brief interval in evolutionary terms but the circumstances were highly unusual, and the process was—to some extent—stimulated and guided by the efforts of mankind. Man himself was by no means immune from the changes he helped to bring about, and the human race—or races, to be strictly accurate—which survived in the Underworld were very different in many ways from the race which survived up above. Even that race—Euchronian man—underwent some evolution during the millennia of the Plan, for the circumstances of that race also necessitated a rate of change somewhat higher than horotelic.

By the time the Euchronian Millennium began, the Underworld had slowed in its evolutionary progress. But the stable horotelic rate which was becoming characteristic of that world was by no means the same as the horotelic rate in the Overworld. In the Underworld there was still a régime of rigorous competition demanding evolutionary divergence. In addition to that there was an extra, and by no means insignificant, load imposed by the high frequency of mutation. The radiation output of the Overworld was directed downwards. Radioactive wastes were disposed of down below, and though they were carefully packaged the rate of leakage was high.

Man—omnivorous, intelligent and at the very highest level of the biotic hierarchy—changed least of the species at that level, and even the human race suffered a tripartite sub-speciation. The species which changed most were the semi-intelligent species which had cohabited with man the concrete jungles of the age of psychosis. Such species had been under considerable adaptive pressure for some centuries before the advent of Euchronia’s Plan. Under the new régime that pressure burst the conceptual barriers which hindered mind development, and three species quickly evolved intelligence of an unusual order.

While the Euchronians began their new life after the Plan had been brought to a successful conclusion, the people of the Underworld were still faced with a fearsome struggle for existence. While the one world settled down to embrace total stability, the other remained in a state of virtual chaos.