What Is Natural?

By Bernd HeinrichJun 1, 1994 5:00 AM


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As I sit on my doorstep facing the rising sun, the air is still cool. The blackflies are not yet out in force, seeking blood meals. But the early-morning coolness does not deter the bumblebees that are humming among chokecherry twigs, seeking the fragrant white flowers to tank up on nectar and to unwittingly produce purple drupes that will feed robins in the fall. The woods nearby ring with the songs of the hermit thrush, myriad warblers, and winter wrens. And in the poplar tree above me a catocalid moth caterpillar, having finished its nocturnal feeding, snips off a leftover leaf remnant to hide any evidence of its feeding. The piece of leaf falls before me into the dewy grass. The caterpillar will now spend the day motionless on a lichen-covered branch, where its camouflage will make it practically invisible to birds, and to me.

There are hundreds--no, hundreds of thousands--of exquisitely elegant and interesting plants and animals all around me, and all are part of the same tree of life that has been growing, expanding, and branching out for some 3.5 billion years. All are part of the "tangled bank" that Charles Darwin first pointed out in 1859 in the Origin of Species. In the concluding paragraph of that book he wrote: "It is interesting to contemplate a tangled bank, clothed with many plants . . . with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us." The tangled bank that so transfixed Darwin was revealed to him in the Galápagos Islands and in the incomparably rich nature of the South American continent. But it is found anywhere on Earth, and everywhere it is adorned with exciting and interesting creations.

My father, one of the last of the naturalist-explorers, introduced me to the wonders of the tangled bank. His experiences were, for him, moments of unparalleled wonder and bliss. Nature was to Papa more beautiful than anything man could devise or even dream of, and his bedtime stories of far-off, unexplored regions were like sermons that spoke for the existence of truth and beauty merely by suggesting what was there. Nature, if seen, would be truth and beauty revealed. On many an evening he'd describe his adventures to me: hunting for extraordinarily rare and secretive birds and their nests; stalking the snoring bird--for New York's American Museum of Natural History--in swamps of sago palms, with their razor-sharp fronds and spines, and ever-present bloodthirsty leeches; or hunting in the Celebes swamps, barefoot and naked to the waist so as to be all the more silent while tracking the quarry he worshiped. I was entranced, and his visions seeped into me as water soaks into a sponge.

Papa, who had little formal academic training, had a deep reverence for the unity of life. Living in nature, he had come to know that life and death are like the head and tail of a coin, part of the same process. The issue was not individual lives, but intact ecosystems that breathed, that lived eternal. They were all part of an integrated fabric in which death grades into life and is inseparable from it.

I remember Papa with fondness and affection. But there was also pain and anger. It had to do with what he called the "eternal laws of nature" and our relationship to them. The tangled bank seemed natural enough. But so was the person on it, for we are part of the same process. And although Darwin had said that the "laws acting around us" referred "in the largest sense" to growth, reproduction, variability, struggle for life, natural selection, and extinction, he never mentioned what they meant in the nitty-gritty, more practical manner--that is, in the smaller sense.

One summer, fresh with a Ph.D. from UCLA and my newly acquired academic wisdom, I questioned the old man. What, I wanted to know, were the "eternal laws of nature" that he seemed to worship and sought to pay obeisance to? What, for that matter, was "natural"?

I don't recall ever getting a straight answer, except for the hazy notion that it somehow referred to "survival of the fittest." These otherwise empty words froze my blood because I remembered he had used them once in another context: our family, in Germany, had survived the war against almost incalculable odds, and he had had no small part in making that happen. But he had invoked this infamous phrase in a personal vein, and with pride, in the same way the social Darwinists had used them to justify exploitation. My mind screamed the unspoken thought: "You mean all those who did not survive are not so worthy?" To me this was reductionism in the extreme.

By reductionism I refer to the expounding of the x of an equation without mentioning the y--being concerned only with causes and not the effects, only with benefits and not the costs. Reductionism is claiming to be "pro-life" because one values embryos, without considering the implications to potential children, to society, to whole ecosystems full of pulsing life. Reductionism is the extrapolation of a sound and worthy concept to the degree that it becomes removed from the larger reality of life. And reductionism is to biology as fundamentalism is to religion, or totalitarianism to government.

Papa felt that the incredible biological complexity he saw in every tangled bank, where a million parts are in a beautiful harmonious whole, "must" have some laws governing it. He "knew" that something as complex as even a single bacterium could not possibly organize itself without some external organizing principle guiding it. Since he saw himself as a realist who did not believe in mythical unproved gods operating by a logic different and separate from the logic of nature, he instead had faith in mythical unproved laws of nature. But neither was defined any better than the other, and ultimately the existence of both leaned on faith instead of proof.

To Papa it was "perfectly obvious" how to determine the practical aspects of the eternal laws of nature: you read nature's book by studying the tangled bank. Each time you studied another bank, you read another page. My father was astute enough to observe (with chagrin) that we humans did not behave very much like many other animals, which were of course natural and therefore wholesome and good. He thought that with civilization we had degenerated, and we no longer knew or heeded the laws of nature.

For humans, laws are of two kinds: religious and secular. One kind calls forth an image of a cosmic judge who declares, "Thou shalt--and if thou dost not obey thou shalt be punished." The other conjures up a municipal judge who says, "Do not drive faster than 55 miles an hour or you will be apprehended and fined." Both kinds of law derive from presumed superior knowledge and, once established, must be obeyed by individuals. But if this is the nature of laws, then the relations that can be construed as natural laws are precisely the opposite. Natural laws are not made by any authority. Instead they are descriptions of how individuals actually do behave when they are given the freedom to act.

The idea that there are laws of nature is old and deeply entrenched, and probably reflects our social nature and our biological propensity to accept hierarchies. Indeed, the deep faith that there are laws sanctioned by a creator of the universe provided the basis for the flowering of early biology. In the nineteenth century biologists were thought of as "natural theologians" who sought to discover God's logic by studying nature. Nature was his handiwork, and presumably it reflected his thoughts. It was our job to read nature in order to find out (and to heed) his designs, his "laws."

In this view, the bee wasn't just fooling around on the flowers. It was working to carry out God's plan to make more plants. And animals didn't engage in sex for the fun of it. Sex was strictly business. Eventually these ideas became accepted without question--as if they were laws created for us.

While the old general idea of God's hand in nature became fossilized in the church, the study of life suddenly experienced an unprecedented revitalization, primarily because of Darwin's discovery of the guiding principle of evolution in the organization of life. A dazzling new "design" of nature was revealed, and it was at first summarized in that famous, chilling phrase "survival of the fittest," which has been interpreted as "eat or be eaten." If this was indeed the lesson to be read from nature, then nature now seemed sinister. And indeed the first horrible reductionism of the new ideas was to use them to justify exploitation, racism, and genocide.

Not surprisingly, natural science soon lost its sex appeal. The separation of church and the study of life became almost complete. Meanwhile, our understanding of nature continued its singular explosion. We learned, for example, about the strange "natural" behavior of apes, how males kill infants not their own, while the mothers immediately mate with the killers and with other males if possible. Ironically, though, we also learned that huge numbers of creatures live in intricate symbiosis with one another; they have evolved to get along with one another, and that is why they survive.

We learned that not all animals have mating systems like cows and sheep, our previous data base. Biologists studied wild, free-living animals and found examples that stretched our concept of what was natural. For example, two male lions may mate with one cooperative female every 15 minutes, day and night, for two days. If the sex life of sheep is "natural," why not that of the lion? Such comparative studies of other animals showed that human sexuality is natural as it is. It is not just for procreation. It may have evolved for maintaining fidelity in pair-bonding. Biological reality has nothing to say about morality, because natural is what is, nothing more.

It is natural for animals to multiply as fast as they can, often with dire consequences. That does not condone the same rapid reproduction for humans, as if there were no consequences. The Catholic Church now gives grudging approval to use of the "natural" (rhythm) method of birth control, which is of course totally unnatural for human beings--it is predicated on the reproductive behavior and physiology of pigs, sheep, and cows. Luckily, the church has failed to bless equally such other perfectly natural phenomena as infanticide, cannibalism, and mass murder.

There is nothing in terms of natural laws or patterns that we should emulate. Our morality is not concerned with obeying laws of nature. Instead it is concerned with facing facts as they relate to a larger plan or vision. Our limited biological morality--which may be partially encoded in genes--concerns rules and behavior relative to our immediate fellow humans. It is natural for us because we are social. Our present conundrum is that we are in need of a larger morality--one that encompasses not the local tribe or village alone but the whole biosphere. Our natural morality once sufficed to keep us moral. Now, however, when we drink a cup of coffee we are affecting rain forests in Colombia. Now by having another baby we are in no small way affecting in the long term the whole globe, and all life on it. Such linkage is a new fact of present reality, and the choices we need to make are not just "natural" biological choices. They are moral ones.

Pope John Paul II, in his attempt to acknowledge the realities of the world, recently pardoned Galileo for his sin of 350 years ago in proposing that the sun does not revolve around Earth. There is much irony here. The pardon makes no difference to the planet or any person on it: we continue on our orbit around the sun regardless of what anyone thinks. The biggest reality of the world is a matter neither of conjecture, belief, nor moral conviction. It is one of incomparable practical urgency. It is one that requires our attention because it affects all of life acutely.

The biggest reality of the world is the great monster now creeping up the tangled bank and threatening to devour it. You can already see its advance--in the dry tears of doomed ghetto children around the world, in the draining of the lush Everglades to make room for tomatoes, in the disappearance of eagles and the wild places they inhabit. Like all great historical monsters, this one, too, is human. And every single year it casts 95 million more of its kind onto the rapidly eroding tangled bank- -the one that is life, and that gives us the very reason and means to live joyously and in awe of the incomparable beauty of Earth.

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