One Human Minute Page 10
IV
How does the new view of life in the Universe differ from the old? We have long known that the birth of life on a planet must be preceded by a long chain of specific events, beginning with the formation of a long-lived and evenly burning star like the Sun, and that this star must create a planetary family. But we did not know that the arms of a spiral galaxy are (or can be) alternate cradles and guillotines of life, depending on the stage of development of the star-generating material when it passes through the spiral and on the place in the arm where the passage occurs.
At the symposium in Burakan I was the only one to hold that the distribution of life-generating heavenly bodies was dependent on events of extraplanetary and extrastellar (galactic) magnitude. Obviously, I, too, was unaware that the chain of events included the motion of the star-generating cloud around the corotational circle; that inside the cloud, the “right” synchronization of astrogenesis and eruptions of supernovas on the cloud’s circumference was necessary; and moreover — conditio sine qua non est longa vita — that the system where biogenesis began had to depart immediately from the spiral’s stormy zone for the calm expanse of space between the arms.
At the end of the seventies it became fashionable to include in cosmological hypotheses a factor called the Anthropic Principle. This factor reduces the enigma of the initial state of the Universe to an argument ad hominem: if conditions had been very different, the question would not have arisen, since there would have been no one to ask it.
It is not hard to see that as a cosmological criterion the Anthropic Principle (the appearance of Homo sapiens was inherent in the Big Bang) has about as much cognitive value as the “Schnapps Principle."
True, the production of schnapps was made possible thanks to the properties of matter in this Universe, but one can perfectly well imagine the history of this Universe, this Sun, this Earth, and this human race without the emergence of schnapps. Schnapps originated because people engaged in the production of different beverages, including those that contained alcohol, sugar, juniper berries, and herbal extracts. This answer is sensible, though general. Whereas to answer the question “How did schnapps come about?” with “It came about because such was the initial state of the Universe” is ridiculous. One might just as well say that Volkswagens or postage stamps owe their existence to the initial state of the Universe. Such an answer explains ignotum per ignotius. It is also a circulus in explicando: that which could arise, did arise. But such an answer ignores the most distinctive property of the proto-Universe. According to the obligatory Big Bang Theory, the Universe was born in an explosion that simultaneously created matter, time, and space.
Traces of this world-creating explosion remain in the Universe to this day as residual radiation present everywhere in the stellar background. In the twenty billion years of the Universe’s existence, the radiation of the first moment has cooled to a few degrees above absolute zero. But that residual radiation ought not to be the same across the whole canopy of sky. The Universe originated from a point of infinitely great density and in the course of 10-35 of a second expanded to the volume of a soccer ball. Even at that moment it was too large and was expanding too rapidly to remain perfectly homogeneous. Causal connections of events are limited by the maximum speed of interaction, which is the speed of light. Such connections were able to last only in regions with dimensions of 10
-25 centimeter, but 1078 such regions could fit in a universe the size of a soccer ball. What took place in some regions, therefore, could not influence the events in others. And therefore the Universe ought to have expanded heterogeneously and not kept the symmetry of those everywhere-identical properties that we nevertheless observe in it. The Big Bang Theory is saved by the hypothesis that in the creational explosion an immense number of universes formed simultaneously. Our Universe was only one of them.
A theory published in 1982 reconciles the homogeneity of the actual Universe with the nonhomogeneity of its expansion through the premise that the proto-Universe was not a universe but a “poliverse.” A poliverse hypothesis can be found in a little book of mine called Imaginary Magnitude, which I wrote ten years earlier, in 1972. The similarity of my speculations to the theories that appeared later gives me courage to speculate further.
Let us recall the champagne bottle that bounced off the football, flew through the open window, and fell into the aquarium. Impossible though it is to calculate the statistical probability of such an accident, we recognize that the accident was possible (that is, it did not contradict the laws of nature; it was not a miracle). And if the bottle had fallen into an aquarium full of stagnant water and dead fish and had splashed, sending a few fish eggs into a bucket of fresh water standing nearby, and if live fish were born from those eggs, it would be an event even rarer, even more exceptional than if there had been no bucket, eggs, or resultant little fish.
Suppose that the children are still playing football; that someone is still tossing champagne bottles out of the second-floor window every now and then; that the next empty bottle, bouncing off the football (which just then intersects the path of its fall), flies into the bucket, so that the little fish born from the roe are splashed out and into butter sizzling on a frying pan. The lady of the house, who had intended to make an omelet, on her return to the kitchen finds little fried fish in the pan.
Would this be an “absolute impossibility"? One cannot maintain that. All one can say is that it was an accident sui generis, one whose full course (beginning with the first champagne bottle) will never be repeated exactly the same way. It is just too improbable. The slightest deviation will cause the bottle not to land in the kitchen, because it will not ricochet off the football “as it should"; or it will break on the floor; or it will sink in the aquarium and nothing more will happen; or it will splash some roe but the roe will not fall into the bucket and produce fish. Then, too, the bucket could be empty, or filled with laundry soaking in a detergent lethal to fish. And so on.
When we bring the Anthropic Principle into cosmology, we are saying that the appearance of man has crowned the evolution of life on Earth with intelligence, since the emergence of intelligent beings becomes more probable the longer that evolution lasts. Leaving the terrain of what today is considered certain or reasonably certain, I will move on to what the science of the next century will contribute to the subject.
V
First, evidence will be gathered showing that the limb of the evolutionary tree that created the mammals would not have branched and would not have given them primacy among the animals had there not been, sixty-five million years ago, between the Cretaceous and Tertiary, a catastrophe in the form of an enormous, 3.5-to-4-trillion-ton meteorite.
Up to that time, the dominant animals were the reptiles. They reigned on land, on water, and in the air for two hundred million years. Attempting to explain their abrupt extinction at the end of the Mesozoic, the evolutionists attributed to these reptiles the traits of contemporary reptiles: cold-bloodedness, primitive organs, and a hairless body covered only by scales or horned armor. And when they reconstructed the appearance and way of life of these animals on the basis of the skeletal fragments found, they did so according to their biases. One could call this “mammal chauvinism.” Paleontologists have said, for example, that the large reptiles, like the brontosaurus, were incapable of moving on dry land and spent their life in shallow water, feeding on plants. Or that the two-legged reptiles, though ambulatory, were awkward, dragging long, heavy tails over the ground. And so on.
Only in the second half of the twentieth century was it learned that the Mesozoic reptiles were as warm-blooded as mammals; that many species — especially the flying ones — had a furlike coat; that the two-legged reptiles did not lumber along dragging their tails, but in speed matched the ostrich, although they weighed up to two hundred times more: the tail, held horizontally by special ligaments, served as a counterweight for the forward-leaning body when it ran. Even the largest saurians moved freely o
n land.
Unable to go into a comparative study of extinct and modern species here, I will give one example of the skill, never since equaled, possessed by certain flying reptiles. The “biological flying record” does not belong to the birds, and still less to the flying mammals, the bats. The largest animal of Earth’s atmosphere was Quetzalcoatlus northrofii, whose body mass exceeded man’s. But it was only one of a group of species given the name Titanopterygia. These were reptiles that glided over the ocean and fed on fish. We do not know how they were able to land and take off, since the weight of their body meant that to do so they would have required a muscular strength beyond that of the animals (and birds) of today. When their fossils were found in Texas and Argentina, it was first thought that these giants of the air, equal in wingspan to a small or even medium plane (thirteen to fifteen meters), spent their lives and built their nests at the top of crags, from which they hurled themselves into the air, spreading their wings. But if they were unable to take off from level ground, they would all, to the last specimen, have been condemned to death if they landed only once in a flat place. Some of these great soarers lived off carrion — but carrion is not found on peaks. Moreover, their enormous bones were found in places devoid of mountains. For experts in aerodynamics, these reptiles present a puzzle. No explanation holds up. A colossus like Quetzalcoatlus could not light on trees; that would cause frequent injury or actual fracture to the wings. The largest specimen of flying bird known is a certain extinct vulture with a wingspan of nearly seven meters; doubling its size quadruples the force needed to rise into the air. The large flying reptiles could not take off by running, either, because their legs were too short and weak.
When the charge of “primitivism” as the cause of extinction was dropped, the opposite replaced it — overspecialization. The reptiles died out, supposedly, because they were too narrowly adapted to their environment; they perished because of a change in climate.
Climatic changes have indeed occurred in the history of the Earth. Everyone knows about the ice ages. The extinction of life at the junction of the Cretaceous and Tertiary periods was also preceded by a cooling; but the cooling did not lead to an ice age. What is more important, no change of climate ever caused the massive extinction of so many species of animals and plants at once. Their fossil remains suddenly vanish in the geological strata of the next period. The figures show that no animal survived whose body weight exceeded twenty kilograms. Never before had there been such a global annihilation. Many invertebrates became extinct then, on land and in the sea almost simultaneously. It was like a biblical plague: day turned into night, and the darkness lasted about two years. Not only could the Sun not be seen anywhere on the Earth’s surface, but its rays provided less illumination than does the full moon. All the large diurnal animals died out. But the small, ratlike mammals, nocturnal scavengers, survived. Out of these remnants of the great zoocide, new species arose during the Tertiary, including the one that bore the fruit of anthropogenesis. The darkness, cutting the Earth off from the Sun’s energy, destroyed most of the green vegetation, since it made photosynthesis impossible. A multitude of algae also died.
I cannot go into more detail now, but, though the mechanism and the consequences of the catastrophe were certainly more complex than is presented here, the scope is the same. The balance sheet looks like this. Man could not emerge from the differentiated biological legacy of the Mesozoic, because that mass represented capital invested in species incapable of anthropogenesis. The investment (as always in evolution) was irreversible; the capital was lost. New capital began to form from the surviving vestiges of life scattered over the Earth. It increased and multiplied until the rise of the hominids and anthropoids.
If evolution’s huge investment in the Thecodontia, Saurischia, Ornithischia, and in the Rhamphorhynchoidea and Pterodactyloidea had not ended in a great crash sixty-five million years ago, the mammals would not have taken over the planet. We owe our existence to that catastrophe. We emerged and multiplied into the billions only because billions of other creatures suffered annihilation. Hence the title, The World as Cataclysm. The scientific search for evidence has led us only to the random author of our species — an indirect albeit a necessary author. It was not the meteor that created us: that only opened the way. The massive destruction that laid waste the Earth thereby made room for more evolutionary experiments. It remains an open question whether, without the meteor catastrophe, intelligence would have appeared on Earth in another form — a nonhuman, nonanthropoid form.
VI
Where there is No One — therefore no feelings, friendly or hostile, no love or hate — there are also no intentions. The Universe, being neither a Person nor the work of any Person, cannot be accused of bias in its action: it simply is what it is and does what it does. What it does is create, again and again, by destroying. Some stars “must” explode and disintegrate so that the heavy elements formed in their nuclear cauldrons can disperse and give a start — billions of years later — to planets and, once in a while, organic life. Others, supernovas, “must” undergo catastrophic destruction in order that galactic clouds of hydrogen, compressed by the explosions, can condense into sunlike, long-lived stars that calmly and steadily warm their family of planets, who also owe their existence to these catastrophes.
But must intelligence, too, begin in lethal cataclysm?
The twenty-first century will not have a definitive answer to that question. It will continue to gather evidence and will fashion a new picture of the world: a collection of random catastrophes governed by precise laws. But it will not provide the final explanation for intelligence.
It will dispel, to be sure, many illusions that persist in science. For example, it will establish beyond any doubt that a brain of high volume is not equivalent to a brain of high intelligence, for which largeness is a necessary but not a sufficient condition. The extraordinary intelligence with which dolphins are supposedly endowed because their brains are larger and more complex than man’s, this dolphin intellect about which so much has been written in our time, will be shown to be a myth. A large brain was indeed needed if the dolphins were to compete successfully in the same ocean with the “stupid” sharks. It allowed them to enter and survive in a niche occupied for millions of years by predator fish — but nothing more.
From this it follows that no statement can be made regarding the chances of intelligence arising among the reptiles had there been no meteor.
A slow but practically constant growth in neural mass characterizes the evolution of all animals, with the exception of certain parasites. But even if that growth were to continue over a time measured in hundreds of millions of years, through the Cretaceous and Tertiary, it would not guarantee the emergence of intelligent saurians.
The crater-pocked surfaces of all the moons in our planetary system are like photographs of the past, a frozen picture of the beginning of this system, which was also created out of destruction. All the bodies orbited the young Sun in frequently intersecting paths, and collisions resulted. Thanks to these catastrophes, the large bodies — the planets — increased in mass, while the bodies of small mass, in colliding with the planets, “vanished” from the system. I said earlier that about 4.6 billion years ago the Sun and its planetary family left the stormy region of the galactic spiral and moved off into calm space. But this does not mean that the interior of the solar system was then calm. Collisions of planets with meteorites and comets were still going on when life began on Earth. Moreover, leaving the spiral arm was not like walking out of a house; radiation and stars do not suddenly cease to exist at any one point. During the first billion years of its existence, the Earth was still continually exposed to shocks, though the supernovas were distant enough not to devastate it and turn it into a dead globe. The hard radiation (X rays and gamma rays) coming from space was a factor both creative and destructive, since it accelerated the rate of mutation in the proto-organisms.
Some insects are a hundred times
less vulnerable to the lethal effect of radioactivity than vertebrates. This is really very strange when you consider that the hereditary substance of all living systems is basically the same. They differ from one another in the way buildings of various cultures, epochs, and architectural styles differ; the building material — brick and stone — is the same everywhere, as is the mortar that keeps the whole together.
The difference in vulnerability to lethal radiation must have been caused by events extremely distant in time, by catastrophes in the era when the first insects (or, rather, their ancestors) came into being, about 430 million years ago. It is not impossible, however, that the “insensitivity” of certain organic forms to radiation fatal to most others developed one billion years ago.
Will the coming century witness a revival of the theory put forth by the early nineteenth-century French paleontologist and anatomist Cuvier, called catastrophism? It saw geological processes, like mountain-formation, climate changes, the rise and disappearance of seas, as violent and sudden transformations — planetary catastrophes. The theory was developed further by Cuvier’s student, d’Orbigny, in the middle of the nineteenth century; according to him, the organic world of the Earth perished and arose anew many times in successive acts of creation.
This union of catastrophism with creationism was laid to rest by Darwin’s theory, but the funeral was premature. Catastrophes on the largest scale, cosmic, are an indispensable condition not only for the evolution of stars but also for the evolution of life. It was the human mind that created the alternative of either “destruction or creation” and that has continued to impose it on the world since the dawn of our history. Man considered the mutual exclusiveness of destruction and creation as self-evident when he faced his own mortality and set it against his will to live. That opposition is the common foundation for all the hundreds of our cultures; one finds it in the most ancient myths, creation legends, and religious beliefs, and in the science that arose a few thousand years later. Faith as well as science endowed the visible world with properties that eliminated blind, incalculable chance as the author of all events. The war of good and evil present in all religions does not always end, in every faith, with the victory of good, but in every one it establishes a clear order of existence. The sacred as well as the profane rest on that universal order. Thus, chance, the ultimate arbiter of existence, was not present in any of the beliefs of the past.[3] Science, too, long resisted acknowledging the creative and incalculable role of chance in the shaping of reality.