".. Physics was the first of natural sciences to become fully modern and highly mathematical. Chemistry followed in the wake of physics, but biology, the retarded child, lagged far behind. Even in the time of Newton and Galileo, men knew more about the moon and other heavenly bodies than they did about their own.
It was not until the late 1940's that this situation changed. The postwar period ushered in a new era of biologic research, spurred by the discovery of antibiotics. Suddenly there was both enthusiasm and money for biology, and a torrent of discoveries poured forth: tranquilizers, steroid hormones, immunochemistry, the genetic code. By 1953 the first kidney was transplanted and by 1958 the first birth-control pills were tested. It was not long before biology was the fastest-growing field in all science; it was doubling its knowledge every ten years. Farsighted researchers talked seriously of changing genes, controlling evolution, regulating the mind-ideas that had been wild speculation ten years before.
And yet there had never been a biologic crisis. The Andromeda Strain provided the first.
According to Lewis Bornheim, a crisis is a situation in which a previously tolerable set of circumstances is suddenly, by the addition of another factor, rendered wholly intolerable. Whether the additional factor is political, economic, or scientific hardly matters: the death of a national hero, the instability of prices, or a technological discovery can all set events in motion. In this sense, Gladstone was right: all crises are the same.
... the first contact with extraterrestrial life will be determinded by the known probabilities of speciation. It is an undeniable fact that complex organisms flourish in abundance. There are millions of species of bacteria, and thousands of species of insects. There are only a few species of primates, and only four of great apes. There is but one species of man.
With this frequency of specication goes a corresponding frequency in numbers. Simple creatures are much more common than complex organisms. There are three billion men on the earth, and that seems a great many until we consider that ten or even one hundred times that number of bacteria can be contained within a large flask.
All available evidence on the origin of life points to an evolutionary progression from simple to complex life forms. This is true on earth. It is probably true throughout the universe .. the first human interation with extraterrestrial life will consist of contact with organisms similar to, if not identical to, earth bacteria or viruses. The consequences of such contact are disturbing when one recalls that 3 percent of all earth bacteria are capable of exerting some deleterious effect upon man.
... In the deepest, blackest regions of the oceans, where oxygentation was poor, and where light never reached, life forms were known to exist in abundance. Why not also in the far reaches of the atmosphere? True, oxygen was scarce. True, food hardly existed. But if creatures could live miles beneath the surface, why could they not also live five miles above it? ... and if there were organisms out there, and if they had departed from the baking crust of the earth long before the first men appeared, then they would be foreign to man. No immunity, no adaptation, no antibodies would have been developed. They would be primitive aliens to modern man, in the same way that the shark, a primitive fish unchanged for a hundred million years, was alien and dangerous to modern man, invading the oceans for the first time .
The third source of contamination, the third of the vectors, was at the same time the most likely and the most troublesome. This was contemporary earth organisms, taken into space by inadequately sterilized spacecraft. Once in space, the organisms would be exposed to harsh radiation, weightlessness, and other environmental forces that might exert a mutagenic effect, altering the organisms. So that when they came down, they would be different.
Take up a harmless bacteria-such as the organism that causes pimples, or sorethroats-and bring it back in a new form, virulent and unexpected. It might do anything. It might show a preference for the aqueous humor of the inner eye, and invade the eyeball. It might multiply on the small currents of electricity afforded by the human brain itself, drive men mad...
.. Most people, when they thought of bacteria, thought of diseases. Yet the fact was that only 3 percent of bacteria produced human disease; the rest were either harmless or beneficial. In the human gut, for instance, there were a variety of bacteria that were helpful to the digestive process. Man needed them, and replied upon them.
In fact, man lived in a sea of bacteria. They were everywhere-on his skin, in his ears and mouth, down his lungs, in his stomach. Everything he owned, anything he touched, every breath he breathed, was drenched in bacteria. Bacteria were ubiquitous. Most of the time you weren't aware of it.
And there was a reason. Both man and bacteria had gottern used to each other, had developed a kind of mutual immunity. Each adapted to the other.
And this, in turn, for a very good reason. It was a principle of biology that evolution was directed toward increased reproductive potential. A man easily killed by bacteria was poorly adapted; he didn't live long enough to reproduce.
A bacteria that killed its host was also poorly adapted. Because any parasite that kills its host is a failure. It must die when the host dies. The successful parasites were those that could live off the host without killing him.
And the most successful hosts were those that could tolerate the parasite, or even turn it to advantage, to make it work for the host.
.. the best adapted bacteria are the ones that cause minor diseases, or none at all..
.. there were hundreds of thousands, perhaps millions, of enzymes, each existing solely to aid a single chemical reactions. Without enzymes, there could be no chemical reactions. Without chemical reactions, there could be no life. Or could there? It was a long-standing problem.
.. How do you study a form of life totally unlike any you know? How would you even know it was alive? This was not an academic matter. Biology, as George Wald had said, was a unique science because it could not define its subject matter. Nobody had a definition for life. Nobody knew what it was, really. The old definitions-an organism that showed ingestion, excretion, metabolism, reproduction, and so on-were worthless. One could always find exceptions.
.. The group had finally concluded that energy conversion was the hallmark of life. All living organisms in some way took in energy-as food, or sunlight-and converted it to another form of energy, and put it to use. (Viruses were the exception to this rule, but the group was prepared to define viruses as nonliving).
.. Finally, they came to the granite. It is living, breathing, walking, and talking. Only we cannot see it, because it is happening too slowly. Rock has a lifespan of three billion years. We have a lifespan of 60 or 70 years. We cannot see what is happening to this rock for the same reason that we cannot make out the tune on a record being played at the rate of one revolution every century. And the rock, for its part, is not even aware of our existence because we are alive for only a brief instant of its lifespan. To it, we are like flashes in the dark ..
.. No one ever thought to consider whether the human brain, the most complex structure in the known universe, making fantastic demands on the human body in terms of nourishment and blood, was not analogous. Perhaps the human brain had become a kind of dinosaur for man and perhaps, in the end, would prove his downfall.
Already, the brain consumed one quarter of the body's blood supply. A fourth of all blood pumped from the heart went to the brain, an organ accounting for only a small percentage of body mass. If brains grew larger, and better, then perhaps they would consume more-perhaps so much that, like an infection, they would overrun their hosts and kill the bodies that transported them.
Or perhaps, in their infinite cleverness, they would find a way to destroy themselves and each other..."
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