"Life at the Edge of Chaos"

The Santa Fe Institute was housed in a series of buildings on Canyon Road which had formerly been a convent, and the Institute's seminars were held in a room which had served as a chapel. Now, standing at the podium, with a shaft of sunlight shining down on him, Ian Malcolm paused dramatically before continuing his lecture.

Malcolm was forty years old, and a familiar figure at the Institute. He had been one of the early pioneers in chaos theory, but his promising career had been disrupted by a severe injury during a trip to Costa Rica; Malcolm had, in fact, been reported dead in several newscasts. "I was sorry to cut short the celebrations in mathematics departments around the country," he later said, "but it turned out I was only slightly dead. The surgeons have done wonders, as they will be the first to tell you. So now I am back - in my next iteration, you might say."

Dressed entirely in black, leaning on a cane, Malcolm gave the impression of severity. He was known within the Institute for his unconventional analysis, and his tendency to pessimism. His talk that August, entitled "Life at the Edge of Chaos," was typical of his thinking. In it, Malcolm presented his analysis of chaos theory as it applied to evolution.

He could not have wished for a more knowledgeable audience. The Santa Fe Institute had been formed in the mid-1980s by a group of scientists interested in the implications of chaos theory. The scientists came from many fields-physics, economics, biology, computer science. What they had in common was a belief that the complexity of the world concealed an underlying order which had previously eluded science, and which would be revealed by chaos theory, now known as complexity theory. In the words of one, complexity theory was "the science of the twenty-first century."

The Institute had explored the behavior of a great variety of complex systems - corporations in the marketplace, neurons in the human brain, enzyme cascades within a single cell, the group behavior of migratory birds - systems so complex that it had not been possible to study them before the advent of the computer. The research was new, and the findings were surprising.

It did not take long before the scientists began to notice that complex systems showed certain common behaviors. They started to think of these behaviors as characteristic of all complex systems. They realized that these behaviors could not be explained by analyzing the components of the systems. The time-honored scientific approach of reductionism - taking the watch apart to see how it worked - didn't get you anywhere with complex systems, because the interesting behavior seemed to arise from the spontaneous interaction of the components. The behavior wasn't planned or directed; it just happened. Such behavior was therefore called "self-organizing."

"Of the self-organizing behaviors," Ian Malcolm said, "two are of particular interest to the study of evolution. One is adaptation. We see it everywhere. Corporations adapt to the marketplace, brain cells adapt to signal traffic, the immune system adapts to infection, animals adapt to their food supply. We have come to think that the ability to adapt is characteristic of complex systems-and may be one reason why evolution seems to lead toward more complex organisms."

He shifted at the podium, transferring his weight onto his cane. "But even more important," he said, "is the way complex systems seem to strike a balance between the need for order and the imperative to change. Complex systems tend to locate themselves at a place we call 'the edge of chaos.'We imagine the edge of chaos as a place where there is enough innovation to keep a living system vibrant, and enough stability to keep it from collapsing into anarchy. It is a zone of conflict and upheaval, where the old and the new are constantly at War. Finding the balance point must be a delicate matter - if a living system drifts too close, it risks falling over into incoherence and dissolution; but if the system moves too far away from the edge, it becomes rigid, frozen, totalitarian. Both conditions lead to extinction. Too much change is as destructive as too little. Only at the edge of chaos can complex systems flourish."

He paused. "And, by implication, extinction is the inevitable result of one or the other strategy -too much change, or too little."

In the audience, heads were nodding. This was familiar thinking to most of the researchers present. Indeed, the concept of the edge of chaos was very nearly dogma at the Santa Fe Institute.

"Unfortunately," Malcolm continued, "the gap between this theoretical construct and the fact of extinction is vast. We have no way to know if our thinking is correct. The fossil record can tell us that an animal became extinct at a certain time, but not why. Computer simtulations are of limited value. Nor can we perform experiments on living organisms. Thus, we are obliged to admit that extinction - untestable, unsuited for experiment - may not be a scientific subject at all. And this may explain why the subject has been embroiled in the most intense religious and political controversy. I would remind you that there is no religious debate about Avogadro's number, or Planck's constant, or the functions of the pancreas. But about extinction, there has been perpetual controversy for two hundred years. And I wonder how it is to be solved if -Yes? What is it?"

At the back of the room, a hand had gone up, waving impatiently. Malcolm frowned, visibly annoyed. The tradition at the Institute was that questions were held until the presentation ended; it was poor form to interrupt a speaker. "You had a question?" Malcolm asked.

From the back of the room, a young man in his early thirties stood. "Actually," the man said, "an observation."

The speaker was dark and thin, dressed in khaki shirt and shorts, precise in his movements and manner. Malcolm recognized him as a paleontologist from Berkeley named Levine, who was spending the Summer at the Institute. Malcolm had never spoken to him, but he knew his reputation: Levine was generally agreed to be the best paleobiologist of his generation, perhaps the best in the world. But most people at the Institute disliked him, finding him pompous and arrogant.

"I agree," Levine continued, "that the fossil record is not helpful in addressing extinction. Particularly if your thesis is that behavior is the cause of extinction - because bones don't tell us much about behavior. But I disagree that your behavioral thesis is untestable. In point of fact, it implies an outcome. Although perhaps you haven't yet thought of it."

The room was silent. At the podium, Malcolm frowned. The eminent mathematician was not accustomed to being told he had not thought through his ideas. "What's your point," he said.

Levine appeared indifferent to the tension in the room. "Just this," he said. "During the Cretaceous, Dinosauria were widely distributed across the planet, We have found their remains on every continent, and in every climatic zone - even in the Antarctic. Now. If their extinction was really the result of their behavior, and not the consequence of a Catastrophe, or a disease, or a change in plant life, or any of the other broad-scale explanations that have been proposed, then it seems to me highly unlikely that they all changed their behavior at the same time, everywhere. And that in turn means that there may well be some remnants of these animals still alive on the earth. Why couldn't you look for them?"

"You could," Malcolm said coldly, "if that amused you. And if you had no more compelling use for your time."

"No, no," Levine said earnestly. "I'm quite serious. What if the dinosaurs did not become extinct? What if they still exist? Somewhere in an isolated spot on the planet."

"You're talking about a Lost World," Malcolm said, and heads in the room nodded knowingly. Scientists at the Institute had developed a shorthand for referring to common evolutionary scenarios. They spoke of the Field of Bullets, the Gambler's Ruin, the Game of Life, the Lost World, the Red Queen, and Black Noise. These were well-defined ways of thinking about evolution. But they were all -

"No," Levine said stubbornly. "I am speaking literally."

"Then you're badly deluded," Malcolm said, with a dismissive wave of his hand. He turned away from the audience, and walked slowly to the blackboard. "Now, if we consider the implications of the edge of chaos, we may begin by asking ourselves, what is the minimal unit of life? Most contemporary definitions of life would include the presence of DNA, but there are two examples which suggest to us that this definition is too narrow. If you consider viruses and so-called prions, it is clear that life may in fact exist without DNA...."

At the back of the room, Levine stared for a moment. Then, reluctantiv he sat down, and began to make notes.