DIVERSITY AS AN ETHICAL GOAL
Edward O. Wilson
They are best seen not on foot or from outer space but through the window of an airplane: the newly cleared lands, the extending web of roads and settlements, the shrinking enclaves of natural habitat. In a glance we are reminded that the once mighty wilderness has shrivelled into timber leases and threatened nature reserves. We measure it in hectares and count the species it contains, knowing that each day something vital is slipping another notch down the ratchet, a million year history is fading from sight.
The loss of wilderness conforms to the original Greek concept of tragedy because it reveals in grave and sombre manner the inexorable workings of the human condition. It presents us with a dilemma that the historian Leo Marx has called the machine in the garden. On the one hand the natural world is the refuge of the spirit, remote, static, richer even than human imagination. But on the other hand we cannot exist in this paradise without the machine that tears it apart. We are killing the thing we love, our Eden, progenitrix and sybil.
Human beings are not natural creatures torn from a sylvan niche and imprisoned within a world of artefacts. The noble savage, a biological impossibility, never existed. The human relation to nature is vastly more subtle and irretrievably ambivalent, for what appears to be the following reason. Over thousands of generations the mind evolved within a ripening culture, creating itself out of symbols and tools, and genetic advantage accrued from planned modifications of the environment. The unique operations of the brain are the result of natural selection operating through the filter of culture. They have suspended us between the two antipodal ideals of nature and machine, forest and city, the natural and the artificial, relentlessly seeking, in the words of the geographer Yi-Fu Tuan, an equilibrium not of this world.
The impossible dilemma caused no problem for ancestral humans. For millions of years human beings simply went at nature with everything they had, scrounging food and fighting off predators across the known world of but a few square miles. Life was short, fate terrifying, and reproduction an urgent priority: children, if freely conceived, could just about replace the family members who seemed to be dying all the time. The population flickered around equilibrium, and sometimes whole bands became extinct. Nature was something out there - nameless, unconfined, and limitless, a force to beat against, cajole, and exploit.
If the machine gave no quarter, then it was also too weak to break the wilderness. But no matter: the ambiguity of the opposing ideals was a superb strategy for survival, so long as the people who used it stayed sufficiently ignorant. It enhanced the genetic evolution of the brain and generated more and better culture. The world began to yield, first to the agriculturists and then to technicians, merchants, and circumnavigators. Humanity accelerated toward the machine antipode, heedless of the natural desire of the mind to keep the opposite as well. Now we are near the end. The inner voice murmurs you went too far and disturbed the world and gave away too much for your control of nature. Perhaps Hobbes' definition is correct and his will be the hell we earned for realising truth too late.
But it is not too late: the actors have not yet left the stage of this particular tragedy. The course of the future can be changed with sufficient knowledge and a strong enough commitment shared by enough people. Like many scientists concerned with the problem, I have emphasised two aspects I consider vital to the development of a better conservation ethic: the appreciation of the loss of wilderness and the lesser natural reserves, and a fuller understanding of the dependence people feel on other forms of life. Let us begin with the first.
Think of scooping up a handful of soil and leaf litter and spreading it out on a white ground cloth, in the manner of the field biologist, for close examination. This unprepossessing lump contains more order and richness of structure, and particularity of history, than the entire surface of all the other planets combined. It is a miniature wilderness that can take almost forever to explore.
Tease apart the adhesive grains with the aid of forceps, and you will expose the tangled rootlets of a flowering plant, curling around the rotting veins of humus, and perhaps some larger object such as the boat-shaped husk of a seed. Almost certainly among them will be a scattering of creatures that measure the world in millimetres and treat this soil sample as traversable: ants, spiders, springtails, armoured oribatid mites, enchytraeid worms, millipedes. With the aid of a dissecting microscope now proceed on down the size scale to the roundworms, a world of scavengers and fanged predators feeding on them. In the hand-held microcosm all of these creatures are still giants in a relative sense. The organisms of greatest diversity and numbers are invisible or nearly so. When the soil-and-litter clump is progressively magnified, first with a compound light microscope and then with scanning electron micrographs, specks of dead leaf expand into mountain ranges and canyons, and soil particles become heaps of boulders. A droplet of moisture trapped between root hairs grows into an underground lake, surrounded by a three-dimensional swamp of moistened humus. The niches are defined by both topography and nuances in chemistry, light, and temperature shifting across fractions of a millimetre. Organisms for which the soil sample is a complete world, now come into view. In certain places are found the fungi: cellular slime moulds, the one-celled chitin-producing chytrids, minute gonapodyaceous and oomycete soils specialists, Kichxellales, Eccrinales, Endomycetales, and Zoopagales. Contrary to their popular reputation, the fungi are not formless blobs, but exquisitely structured organisms with elaborate life cycles worthy of their exotic titles.
Still smaller than the parasitic fungi are the bacteria, including colony-forming polyangiaceous species, specialised predators that consume other bacteria. All around them live rich mixtures of rods, cocci, coryneforms, and slime azotobacteria. Together these micro-organisms metabolise the entire spectrum of live and dead tissue. At the moment of discovery some are actively growing and fissioning, while others lie dormant in wait for the right combination of nutrient chemicals. Each species is kept at equilibrium by the harshness of the environment. Any one, if allowed to expand without restriction for a few weeks, would multiply exponentially, faster and faster, until it weighed more than the entire earth. But in reality the individual organism simply dissolves and assimilates whatever appropriate fragments of plant and animal that come to rest near it. If the new-found meal is large enough, it may succeed in growing and reproducing briefly before receding back into the more normal state of physiological quiescence.
In other words, biologists have begun a reconnaissance into a land of magical names. In exploring life they have commenced a pioneering adventure with no imaginable end. The abundance of organisms increases downward by level, like layers in a pyramid. The handful of soil and litter is home for hundreds of insects, nematode worms, and other larger creatures, about I million fungi, and 10 billion bacteria. Each of the species of these organisms has a distinct life cycle fitted to the portion of the micro-environment in which it thrives and reproduces. The particularity is due to the fact that it is programmed by an exact sequence of nucleotides, the ultimate molecular unit.
The amount of information in the sequence can be measured in bits in the following way. One bit is the information required to determine which of two equally likely alternatives is chosen, such as heads or tails in a coin toss. The English language averages two bits per letter. A single bacterium possesses about 10 million bits of genetic information, a fungus 1 billion, and an insect from 1 to 10 billion bits according to species. If the information is just one insect - say an ant or beetle - were to be translated into a code of English words and printed on letters of standard size, the string would stretch over 1,000 miles. The lump of earth contains information that would fill all fifteen editions of the Encyclopaedia Britanica.
I invite you now to try to visualise the loss in biological diversity due to the reduction of natural habitats. If so much complexity of information can be held in the cupped hands, think of how much more exists in an entire habitat. Consider the loss, mostly invisible to us today but destined to be painfully obvious to our descendants, that occurs when an entire wilderness area is degraded or destroyed.
It is an issue that turns otherwise cautious scientists into outspoken activists. On a worldwide basis, extinction is accelerating and could reach ruinous proportions during the next twenty years. Not just birds and mammals are vanishing but such smaller forms as mosses, insects, and minnows. A conservative estimate of the current extinction rate is 1,000 species per year, mostly because of the destruction of forests and other key habitats in the tropics. By the 1990s, the figure is expected to rise past 10,000 species a year (one species per hour). During the next thirty years, fully 1 million species could be erased.
Whatever the exact figure - and the primitive state of evolutionary biology permits us only to set broad limits - the current rate is at least the greatest in recent geological history. It is also much higher than the rate of production of new species by ongoing evolutionary processes, so that the net result is a steep decline in global biological diversity. Whole categories of organisms that emerged over the past 10 million years, among them the familiar condors, rhinoceros, manatees, and gorillas, are close to the end. For most of their species, the last individuals to exist in the wild state could well be living there today. It is a grave error to dismiss the haemorrhaging as a "Darwinian" process, in which species autonomously come and go and humans are just the latest burden on the environment. Human destructiveness is something new under the sun. Perhaps it is matching the giant meteorites thought to smash into the earth and darken the atmosphere every 100 million years or so ( the last one apparently arrived 65 million years ago and contributed to the extinction of the dinosaurs). But even that interval is 10,000 times longer than the entire history of civilisation. In our own brief lifetime humanity will suffer an incomparable loss in aesthetic value, practical benefits from biological research, and worldwide biological stability. Deep mines of biological diversity will have been dug out and carelessly discarded in the course of environmental exploitation, without our even knowing fully what they contained.
These calculations lend great importance to the National Wilderness Preservation System in our own country and underscore the need to both enlarge and strengthen it. The 1964 Wilderness Act that created the program is sound in philosophy, but its implementation thus far fails grievously short of protecting the American heritage of living diversity. Of the 233 distinct ecosystems recognised by the Forest Service in the United States and Puerto Rico, only 81 are represented in the National Wilderness Preservation System. Another 102 ecosystems could be set aside within the domain of federally owned undeveloped lands.
In the end, the problem of wilderness preservation is a moral issue, for us and for our descendants. It is a curious fact that when very little is known about a subject, the important questions people raise are ethical. Then as knowledge grows, they become more concerned with information than with morality, in other words more narrowly intellectual. Finally, as understanding becomes sufficiently complete, the questions turn ethical again. Environmentalism is now passing from the first to the second phase, and there is reason to hope that it will proceed directly on to the third.
The future of the conservation movement depends on such an advance in moral reasoning. Its maturation is linked to that of biology and the new hybrid field, bioethics, that deals with the many technological advances recently made possible by biology. Philosophers and scientists are applying a more formal analysis to such complex and difficult problems as the allocations of scarce organ transplants, heroic but extremely expensive efforts to prolong life, and the possible use of genetic engineering to alter human heredity. They have only begun to consider the relationships between human beings and organisms with the same rigor. It is clear that the key to precision lies in the understanding of motivation, the ultimate reasons why people care about one thing but not another - why, for example, they prefer a city with a park to a city alone. The goal is to join emotion with the rational analysis of emotion in order to create a deeper and more enduring conservation ethic.
Aldo Leopold, the pioneer ecologist and author of A Sand Country Almanac, defined an ethic as a set of rules invented to meet circumstances so new or intricate, or else encompassing responses so far in the future, that the average person cannot foresee the final outcome. What is good for you and me at this moment might easily sour within ten years, and what seems ideal for the next few decades could ruin future generations. That is why any ethic worthy of the name has to encompass the distant future. The relationships of ecology and the human mind are too intricate to be understood entirely by unaided intuition, by common sense - that overrated capacity defined by Einstein as the set of prejudices we acquire by the age of eighteen.
An enduring code of ethics is not created whole from absolute premises but inductively, in the manner of common law, with the aid of case histories, by feeling and consensus, though an expression of knowledge and experience, influenced by an understanding of human needs and mental development, during which well-meaning and responsible people sift the opportunities and come to agree upon norms and directions.
Why then should the human race protect biological diversity? Let me count the ways. The first is that we are part of life on earth, share its history, and hence should hesitate before degrading and destroying it. The acceptance of this principle does not diminish humanity but raises the status of nonhuman creatures. We should at least pause and give reason before treating them as disposable matter. Peter Singer, a philosopher and animal liberationist, has gone so far as to propose that the circle of altruism be expanded beyond the limits of our own species to animals with the capacity to feel and suffer, just as we have extended the label of brotherhood steadily until most people now feel comfortable with an all-inclusive phrase, the family of man. Christopher D. Stone, in Should Trees Have Standing?, has examined the legal implications of this enlarged generosity. He points out that until recently, women, children, aliens, and members of minority groups had few or no legal rights in many societies. Although the policy was once accepted casually and thought congenial to the prevailing ethic, it now seems hopelessly barbaric. Stone asks, why should we not extend similar protection to other species and to the environment as a whole? People still come first - humanitarianism has not been abandoned - but the rights of the owners should not be the exclusive yardstick of justice. If procedures and precedents existed to permit legal action to be taken on behalf of certain agreed upon parts of the environment, the argument continues, humanity as a whole would benefit. I am not sure I agree with this concept, but at the very least it deserves more serious debate than it received. Human beings are a contractual species. The working principles of ownership and privilege are arrived at by long-term mutual consent, and legal theorists are long way from having explored their ultimate limits.
If nobility is defined as reasoned generosity beyond expedience, animal liberation would be the ultimate ennobling act. Yet to force the argument entirely within the flat framework of kinship and legal rights is to trivialise the case favouring conservation, to justify one set of ethical beliefs (conservation, animal rights) on the basis of another (kinship, human rights). It is also very risky. Human beings, for all their professed righteousness and brotherhood, easily discriminate against strangers and are content to kill them during wars declared for relatively frivolous causes. How much easier it is to find an excuse to exterminate another species. A stiffer dose of biological realism appears to be in order. We need to apply the first law of human altruism, ably put by Garret Hardin: never ask people to do anything they consider contrary to their own best interests. The only way to make a conservation ethic work is to ground it in ultimately selfish reasoning - but the premises must be of a new and more potent kind.
An essential component of this formula is the principle that people will conserve land and species fiercely if they foresee a material gain for themselves, their kin, and their tribe. By this economic measure alone the diversity of species is one of the earth's most important resources. It is also the least utilised. We have come to depend completely on less than 1 percent of living species for our existence, with the remainder waiting untested and fallow. In the course of history, according to estimates recently made by Norman Myers, people have utilised about 7,000 kinds of plants for food, with emphasis on wheat, rye, maize, and about a dozen other highly domesticated species. Yet at least 5,000 exist that are edible, and many of these have traits superior to those of the crop plants in use. The strongest of all arguments from surface ethics is a logical conclusion about this unrealised potential: the more the living world is explored and utilised, the greater will be the efficiency and reliability of the particular species chosen for economic use. Among the potential star species are the following.
Even with limited programmes of research, biologists have compiled an impressive list of such candidate organisms in the technical literature. The vast majority of wild plants and animals are not known well enough (almost certainly many have not even been discovered) even to guess at those with the greatest economic potential. Nor is it possible to imagine all the uses to which each species can be put.
Consider the case of the natural food sweeteners. Several species of plants have been identified whose chemical products can replace conventional sugar with negligible calories and no known side effects. The katemfe (Thaumatococcus danielli) of the West African forests contains two proteins that are 1,600 times sweeter than sucrose and are now widely marketed in Great Britain and Japan. It is outstripped by the well-named serendipity berry (Dioscoreophyllum cumminsii), another West African native whose fruit produces a substance 3,000 times sweeter than sucrose.
Natural products have been called the sleeping giants of the pharmaceutical industry. One in every ten plant species contains compounds with some anticancer activity. Among the leading successes from the screening conducted thus far is the rosy periwinkle, a native of the West Indies. It is the very paradigm of a previously minor species, with pretty five-petaled blossoms but otherwise rather ordinary in appearance, a roadside casual, the kind of inconspicuous flowering plant that might otherwise have been unknowingly consigned to extinction by the growth of sugarcane plantations and parking lots. But it also happens to produce two alkaloids, vincristine and vinblastine, that achieve 80 percent remission from Hodgkins' disease, a cancer of the lymphatic system, as well as 99 percent remission from acute lymphocytic leukaemia. Annual sales of the drugs reached $100 million in 1980.
A second wild species responsible for a medical breakthrough is the Indian serpentine root (Rauwolfia serpentina). It produces reserpine, a principal source of tranquillisers used to relieve schizophrenia as well as hypertension, the generalised condition predisposing patients toward stroke, heart malfunction, and kidney failure.
The natural products of plants and animals are a select group in a literal sense. They represent the defence mechanisms and growth regulators produced by evolution during uncounted generations, in which only the organisms with the most potent chemicals survived to the present time. Placebos and cheap substitutes were eliminated at an early stage. Nature has done much of the work for us, making it far more efficient for the medical researcher to experiment with extracts of living tissue than to pull chemicals at random off the laboratory shelf. Very few pharmaceuticals have been invented solely from knowledge of the principles of chemistry and medicine. Most have their origin in the study of wild species and were discovered by the rapid screening of large numbers of natural products.
Natural products also have been utilised in achieving many industrial and agricultural technological advances. Among the most important have been the development of phytoleum, new plant fuels to replace petroleum; waxes and oils produced from indefinitely renewing sources at more economical rates than previously thought possible; novel kinds of fibres for paper manufacture; fast growing siliceous plants, such as bamboo and elephant grass, for economical dwellings; superior methods of nitrogen fixation and soil reclamation; and "magic bullet" techniques of pest control, by which micro-organisms and parasites are set loose to find and attach target species without danger to the remainder of the ecosystem. Even the most conservative extrapolation indicates that many more discoveries will result from just a modest continuation of such research efforts.
Furthermore, the direct harvesting of free-living species is only a beginning. The favoured organisms can be bred over about ten to one hundred generations to increase the quality and yield of their desired product. It is possible to create new strains that do well in new climates and the special environments required for mass production. The genetic material comprising them is an additional future resource; it can be taken apart gene by gene and distributed to other species. Thomas Eisner, one of the pioneers of chemical ecology, has used a striking analogy to explain these two levels of utilisation of wild organisms. Each of the millions of species can be visualised as a book in a library. No matter where it originates, it can be transferred and put to use elsewhere. No matter how rare in its original state, it can be copied many times over and disseminated to become indefinitely abundant. An orchid down to the last hundred individuals in a remote valley of the Peruvian Andes, which also happens to be the source of a medicinal alkaloid, can be saved, cultured, and converted into an important crop in gardens and greenhouses around the world. But there is much more to the species than the alkaloid or some other useful material that it happens to package. It is not really a conventional book; it is more like a loose-leaf notebook in which the genes are the equivalent of detachable pages. With new techniques of genetic engineering, biologists will soon be able to lift out desirable genes from one species or strain and transfer them to another. A valuable food plant, for example, can be given DNA from wild species conferring biochemical resistance to its most destructive disease. It can be altered by parallel procedures to grow in desert soil or through longer seasons.
A notable case in point is the primitive form of maize, Zea diploperennis, recently discovered in a mountain forest of south-western Mexico. It survives only in three small areas totalling a mere ten acres (at any time a bulldozer might easily have extinguished the entire species within hours). Zea diploperennis possesses genes for perennial growth, making it unique among all other known varieties of corn. It is thus the potential source of a hereditary trait that could reduce growing time and labour costs, making cultivation more feasible in ecologically marginal areas.
Finally, beyond such practical concerns and far more difficult to put into words, is what biological diversity means to the human spirit. This is what can be called the deep ethic as opposed to the surface ethic of conservation. It is ultimately more convincing and durable and takes approximately the following form. We are human in good part because of the particular way we affiliate with organisms. They are the matrix in which the human mind originated and is permanently rooted, and they offer the virtually endless challenge and freedom innately sought. The scientist is perhaps for the moment more aware than most of the opportunities for discovery and the unending sense of wonder that the living world offers - bear in mind the 1,000 miles of mostly new information in each handful of soil. To the extent that each person can feel as a naturalist, the old excitement of the untrammelled world will be regained. I offer this then as a formula of reenchantment to reinforce poetry and myth: mysterious and little known organisms still live within reach of where you sit. Splendour awaits in minute proportions.
The counterargument to a conservation ethic of any kind is that people come first. After their problems have been solved we can enjoy the natural environment as a luxury. If that is indeed the answer, the wrong question was asked. The question of importance concerns purpose. Let us assume that human genius has the power to thread the needles of technology and politics. Let us imagine that we can avert nuclear war, feed a stabilised population, and generate a permanent supply of energy - what then? The answer is the same all around the world: individuals will strive toward personal fulfilment and at least realise their potential. But what is fulfilment, and for what purpose did human potential evolve?
The truth is that we never conquered the world, we never understood it, we only thought we had taken control. We do not even know why we respond in a certain way to other organisms and need them in divers ways so deeply. The prevailing myths concerning our predatory actions toward each other and the environment are obsolete, unreliable, and destructive. The more the mind is fathomed in its own right, as an organ of survival, the greater will be the reverence for life for purely rational reasons.
Science and natural philosophy have brought into clear relief the following paradox of human existence. The drive toward perpetual expansion - or if you prefer, personal freedom - is basic to the human spirit. But to sustain it we need the most delicate knowing stewardship of the living world that can be devised. Expansion and stewardship may appear at first to be conflicting goals, but they are not. The depth of the conservation ethic will be measured by the extent to which each of the two approaches to nature is used to reshape and reinforce the other. The paradox can be resolved by changing its premises into forms more suited to ultimate survival, by which I mean protection of the human spirit.
Edward O. Wilson, at the time of writing this article in 1984, was Baird Professor of Science at Harvard and curator of entomology at the university's Museum of Comparative Zoology, and one of the first scientists to perceive a relationship between population biology and the social structure of all organisms, including human beings. He is the author or co-author of numerous books, including Sociobiology: The New Synthesis (1975) and On Human Nature, which won the 1979 Pulitzer Prize for general non-fiction. His article is based upon portions of a forthcoming book, Biophilia: The Human Bond to Other Species, to be issued by the Harvard University Press.
Source: Wilderness, 1984.