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PART 1—
DEFINING BIODIVERSITY



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Page 9 PART 1— DEFINING BIODIVERSITY

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Page 11 Barriers to Perception: From a World of Interconnection to Fragmentation David T. Suzuki The Suzuki Foundation, 2211 West 4th Ave., Suite 219, Vancouver, BC V6K 4S2, Canada Making Sense of the Cosmos The great molecular biologist and Nobel laureate Francois Jacob has stated that the human brain has a built-in need for order. From earliest times, human beings looked out and recognized cycles, repetitive patterns in nature—day following night, the seasons, tides, lunar cycles, plant succession, animal migration—that conferred the ability to predict their recurrence, and thus people acquired a semblance of understanding of and control over the cosmic forces impinging on their lives. Gifted with an enormous brain, our distant ancestors were inquisitive, experimental, and inventive. Over time, they acquired profound insights into their immediate surroundings that had conferred survival value. No doubt they pondered many of the same cosmic questions that we ask today: How did we get here? Where are we going? What is the meaning of life? As the great French anthropologist Claude Lévi-Strauss wrote: I see no reason why mankind should have waited until recent times to produce minds of the caliber of a Plato or an Einstein. Already over two or three hundred thousand years ago, there were probably men of similar capacity (Lévi-Strauss 1968). From the dawn of human awareness, people accumulated insights and understanding and superstitions that were woven into their mythologies, into the fabric of their culture and identity. Anthropologists call this a “worldview”; in it, nothing exists in isolation from anything else. The rocks, the wind, the stars, the

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Page 12 rivers, the forests,and people are all inseparably intertwined. The past, the present, and the future form a seamless flowing continuum. In such a world, human beings often were saddled with enormous responsibility to keep it all going. They had to behave properly, say the right prayers, and follow the proper rituals and ceremonies, or the world could collapse. So the great bounty of the world of which humans partook was laden with responsibility. From Interconnection to Fragmentation When Francis Bacon recognized that knowledge (scientia) is power, he began a fundamental shift in how we perceive our surroundings. Science is a radically different way of seeing the world. Instead of trying to understand the whole universe, scientists focus on a part of nature, separate it from its surroundings, control everything impinging on it, measure everything within it, and thereby acquire profound insights into that isolated bit of nature. Ever since Newton described the universe as an immense clockwork mechanism, scientists have been motivated by the notion that by analyzing nature in fragments, we could eventually understand the whole by putting the pieces together as in a giant jigsaw puzzle. Reductionism is at the heart of modern science. Physicists recognized in this century that reductionism does not work. The universe is not like a giant machine. Quantum mechanics revealed that at the most fundamental level of subatomic particles we could not know their precise location with certainty, only by statistical probability. Furthermore, as Nobel laureate Roger Sperry pointed out, properties emerge from the interactions of parts of nature that cannot be predicted on the basis of the individual properties of the parts (Sperry 1968). However, most of biology and medicine remains predicated on reductionism. In this century, humankind has undergone massive changes with explosive speed. Harnessing the enormous power of technology, increasing in number exponentially, and accepting a global economy based on endless growth and productivity, we have become a superspecies capable as no other species has ever been of modifying the biophysical features of the planet on a geological scale. In a moment of evolutionary time, great rivers can be diverted or dammed, wetlands drained, ancient forests cleared, and air, water, and soil polluted. As technology and the economy have become the dominant elements of our lives, worldviews have been shattered, and we are no longer able to recognize the exquisite interconnections that mean that every human action has enormous repercussions throughout the biological world. As Thomas Berry says: It's all a question of story. We are in trouble just now because we do not have a good story. We are in between stories. The old story, the account of how we fit into it, is no longer effective. Yet we have not learned the new story (Berry 1988). The challenge we face is to rediscover those connections and recognize that we remain embedded in nature so our every action is laden with consequences

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Page 13 and ramifications. The difficulty is that we have barriers that blind us to those interconnections. If we are to pass through the barriers, we first have to recognize them. Barriers to Interconnectedness The Move to Cities. If we look at humankind over the vast sweep of evolutionary time, one of the monumental transitions has been the change in this century in how we live. In 1900, only 16 cities had a million or more people. The largest was London, with 6.5 million. Tokyo was seventh, with 1.5 million. More than 95% of humanity lived in rural village communities. We were an agrarian species. Today, over 400 cities have a million or more people. The top 10 all have more than 11 million, and Tokyo is the largest with 26.5 million! Over half of all people now live in large urban settings, and the proportion is increasing all the time (World Almanac 1996). Designed properly, cities could be ecologically far more benign in energy use, pollution, use of cars, and so on. But in cities, we live in a human-created habitat that is severely diminished in biological diversity. Our surroundings are dominated by one species—us—and the few plants and animals that we decide to share space with or cannot quite eliminate. In such an environment, it becomes easy to think that we are special, that our creativity has enabled us to escape the constraints of our biological nature. It is easy to forget that we remain absolutely dependent on air, water, soil, energy, and biodiversity for our survival and good health. I have been shocked while making television programs by the number of urban children (and adults) who have little idea of the source of their food. Many do not know that vegetables grow in the “dirt” or that wieners, hamburgers, and drumsticks are the muscles of animals. They do not know where electricity, water, plastic, or glass comes from or where sewage and garbage go. Yet they are all services delivered not by the economy, but by Earth itself. Science and Technology As a student in the immediate post-Sputnik years, I was taught and believed that science enables us to push back the curtains of ignorance to unlock the deepest secrets of the universe and thereby to acquire the understanding that is vital to control and manage the world around us. Progress in science during this century has been spectacular; in my field of genetics, it takes my breath away to see techniques used in undergraduate laboratories that I never dreamed would be available in my lifetime. And the technological prowess that accompanies our insights is truly phenomenal. But in our understandable exuberance over our discoveries, we forget how science progresses, and we forget the extent of our ignorance. When I graduated as a fully accredited geneticist in 1961, I thought I was pretty hot. I knew about DNA and operons and cistrons. But now when I tell

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Page 14 students about our 1961 ideas of chromosome structure, gene function, and regulation, they laugh in disbelief. Seen through the perspective of what we know in 1997, our hotshot ideas of 1961 are naive and far off the mark. But students are stunned when I remind them that when they have been professors for 20 years and tell their students what the hottest ideas of 1997 were, those students will also be highly amused. The very nature of science is that we know that most of our current ideas, models, and hypotheses are wrong, in need of major modification, or irrelevant. As we rush to patent and apply ideas and techniques in molecular biology, we remain ignorant about the makeup and extent of biological diversity on the planet. As E.O. Wilson has argued, the 1.6 million species identified may be less than 20% of all species on Earth (Wilson 1992). And identification of a species merely means that a biologist has classified and named a dead specimen; it does not mean that we know anything about how many individuals there are, the distribution of the species, how it interacts with other species, or anything about its basic biology. We are tearing at the intricate web of living things before we have any understanding of its components or how they interact to maintain the planet's productivity. Our basic descriptive research is imperative. Currently, the strength of scientists is description: because we know so little, we make discoveries wherever we look. But for the same reason, we cannot be prescriptive in recommending meaningful action for environmental problems that we encounter. Rachel Carson's 1962 seminal book Silent Spring was a warning that technology, however beneficial, invariably has costs, and because our knowledge is still so limited, our capacity to anticipate or predict all consequences and costs is extremely restricted. When the insecticidal properties of some molecules were discovered, the benefits of killing insect pests were obvious. At that time, geneticists knew enough to predict that resistant mutants would quickly render an insecticide ineffective, and ecologists understood that the use of broad-spectrum insecticides made little ecological sense when fewer than one-thousandth of all insect species are pests to human beings. But no one could have anticipated the biomagnification of insecticides, because scientists discovered the phenomenon only when populations of some birds, such as eagles, decreased drastically. If we cannot anticipate the consequences of powerful new technologies and if our knowledge of the basic biological and physical makeup of Earth is minuscule, can we go on embracing new technologies with the hope that the inevitable problems that they create will be correctable by further technological innovation? I don't see how we can. The Information Explosion Today, as we prepare to leap into a new millennium, our leaders wax eloquent and ecstatic about the information superhighway that will take us there. But having worked as both a university professor and a host in television and radio since 1962, I can tell you that the challenge we face today is not a need for access to more information but a way of wading through information overload. The average person today is confronted with “info-glut,” and most of what passes as information is junk. On an anecdotal level, I encounter many

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Page 15 people who regale me with fantastic ideas—Bermuda triangles, extraterrestrial abductions, or scientific breakthroughs—and when I ask the source of their stories, the answer is often “I read it” or “I saw it on TV.” But if people do not make a distinction between information obtained from the National Enquirer and information obtained from Scientific American or the New Scientist, or between Geraldo Rivera and The Nature of Things or Nova, then information is validated simply on the grounds that it exists. And the nature of the electronic media is that they create a virtual reality that is better than the real thing. After all, you can now experience the kinkiest sex without fear of being caught or catching AIDS; you can lose a gunfight and live to fight again; you can have a horrendous crash in a car race and walk away. When I began my career in television, I had the great conceit to think that through this medium I would create films that would stand out like jewels, entertaining while educating the viewing public. My hope was that with good natural-history films people would grow to love and value the wonderful diversity of other species and complex ecosystems. But I have learned that our programs, too, are a form of virtual reality. Years ago, I was on a talk show on national television, and the host asked me, “As a scientist, what do you think the world will be like in 100 years?” I responded that if human beings are still around in a century, I would hazard a guess that they would curse us for two things—nuclear power and television. Ignoring the nuclear issue, the host did a double take and stammered, “Why television?” My response was “Bob, you asked me a very tough question. If I had responded ‘Gee, Bob, that's a hard one’ and then proceeded to think for 10 seconds, you would have cut to commercials within 3 seconds. Because television is not serious, it cannot tolerate dead air.” Now in reflecting on that exchange, I have recognized that when we assemble a nature film, we create an artifact: we send a photographer to the Arctic or the Amazon for months to get all kinds of shots-to-end-all-shots. Then in an editing room, we string them all together to produce an illusion that a tropical rain forest or the Arctic is a blur of activity. But the one ingredient that is indispensable to experience the real world is time. As telecommunication technology jams more and more information into less and less space, it delivers more jolts per second to an audience now hooked on and demanding more and more adrenaline-charged jolts. And the overriding message within the medium, even for a public-supported medium like the Canadian Broadcasting Corporation, is consume, consume, consume. As Thomas Veltre of the New York Zoological Association has pointed out, the underlying message in television is diametrically opposed to that of environmentalism (Veltre 1990). Those of us concerned with sustainable futures look at the world on a geological time scale; we try to see the whole picture, and we urge conservation. Information conveyed by the electronic media is conveyed as a series of unrelated bullets conveying little sense of the context and history that give us an understanding of why they matter. We are assaulted by instant and fragmented factoids; and throughout, we are exhorted to buy, buy, buy.

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Page 16 Politics, Politicians, and Bureaucracy Now that the ideological battle and insane arms race between the Soviet Union and the United States has ended, we revel in the apparent triumph of democracy and the efficiency of the global market. But there are enormous ecological problems that governments on any side of the political spectrum are ill equipped to handle. To begin with, political action is predicated on the need to obtain tangible results in time for the next election, a timeframe that is too short to deal seriously with many of our most important challenges, such as species extinction and climate change. Thus, for example, in a study initiated by Prime Minister Brian Mulroney in 1988, it was found that Canada could readily achieve a 20% reduction in CO2 emission in 15 years for a net savings of $150 billion! That apparent good news has never been formally released, and nothing was ever done to implement it. That is because to achieve the CO2 reduction and save an enormous sum, an initial $74 billion has to be invested. It would be political suicide to announce such an up-front expenditure; besides, the political beneficiary of the savings would be someone else 15 years later. A further problem that I have found in Canada is that elected politicians come primarily from two professions: business and law. In part, that reflects the fact that few people from labor, farming, homemaking, teaching, and so on can afford to run for office and lose. But this skewed representation distorts perceptions of government priorities. It is not an accident that in my country there is excessive concern with economic and jurisdictional issues. In the last session of Parliament, of more than 600 questions asked during Question Period, a mere seven were on the environment, but many concerned Quebec separation, gun control, and athletics. To compound the limited perspectives of government, when 50 members of Parliament were tested for their comprehension of scientific and technological terms and concepts, lawyers and businesspeople scored at the absolute rock bottom of the heap. Yet they will make decisions about the future of old-growth forests, climate change, ozone depletion, toxic pollution, genetic engineering, artificial intelligence, and many other issues requiring an understanding of science and technology. Clearly, the challenge is to make science and technology a fundamental part of every citizen's education. Perhaps the greatest challenge is that political priorities are defined by a profound species chauvinism that blinds us to larger ecological principles. Once elected to office, politicians are beholden to financial backers, their party, and the electorate, apparently in descending order of importance. But children do not vote. For that matter, future generations do not vote. Yet they are the ones with the most at stake in the decisions now being made by governments. In addition, our governments' priorities are too restricted along species lines to enable them to assess ecological problems adequately. Thus, we create political boundaries that we then deploy every effort to protect. But human borders make little ecological sense to air, water, plants, and animals. Watersheds, mountaintops, ozone layer, valley bottoms, jet streams, wetlands, flyways, ocean currents—these are the real ecological determinants of meaningful boundaries.

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Page 17 Nothing illustrates better the ludicrousness of our political attempts to manage nature than Pacific salmon, which currently inflame American and Canadian political rhetoric. Adults of the five species of salmon know very well where they “belong”: in the natal rivers and streams that they left 2–5 years before. But because fishing fleets intercept them at sea, we must establish an International Salmon Commission to set quotas for each nation. As the animals move from Alaska past British Columbia to Washington, Oregon, and California, fishers take them in the open sea as though the fish belong to them. Even when the fish reach their river homes in British Columbia, the federal government decrees that they fall under the Department of Indian Affairs for the aboriginal food fishery and the Department of Fisheries and Oceans for the commercial fishers, while the provincial government claims the highest revenue from sport fishing, which falls under the Department of Tourism. As the salmon move up the rivers, activities administered under the Departments of Urban Affairs, Mining, Agriculture, Forestry, and Science and Technology impinge on their fate. So human categories and priorities transform what is a single biological issue into a multiplicity of bureaucratic turf wars, thereby making it certain that the fish will never be dealt with in a way that will ensure their long-term survival and abundance. When politicians attempt to bring “all the stakeholders” to the table to hash out a contentious issue—such as clear-cutting old-growth forests, damming a river, or building a new nuclear facility—the most important stakeholders are not present. Where are the children, the unborn generations, the fish, air, trees, water, or topsoil? Our minister of forests does not speak on behalf of the forest, nor the minister of agriculture on behalf of the soil, nor the minister of fisheries on behalf of the fish. Instead, we attempt to shoehorn nature into the demands of human economic, political, and social priorities, often rationalizing our actions by claiming that environmental assessments permit them. In Canada, environmental regulations are often suspended because of the need to stimulate the economy or create jobs. In our position of dominance, we now assume that the planet is a massive resource that is ours to exploit as we wish. Thus, the 1987 UN Commission on the Environment and Development report Our Common Future suggested a goal of protecting 12% of the land in every country. Canada does not come close to that target either federally or provincially, and there has been vehement opposition to attempting to achieve it. It is assumed that human beings—one of perhaps 10–30 million species—have the right to exploit 88% of the land! The Global Economy Finally, we are being sold on a kind of global economics that runs counter to what we have learned from biology in the second part of the century. In the early 1960s, geneticists began to apply the tools of molecular biology to look at the products of single genes within a species. To their amazement, they discovered that there was a tremendous amount of genetic polymorphism. Now we understand that genetic diversity is the key to a species's resilience and adaptability as the environment changes. It also appears that species diversity within ecosystems

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Page 18 and ecosystem diversity around the world are also critical elements in life's resilience. Humans have added another level of diversity that is important for our species's resilience: culture. Human cultures are profoundly local and have enabled groups of our species to survive and flourish in environments as different as the Arctic, grasslands, mountain ranges, steaming jungles and rain forests, and arid deserts. We even flourish in New York, Tokyo, and London, for Heaven's sake! We have learned that when we attempt to raise large numbers of organisms of a single species or one genetic strain of animal or plant, that population becomes extremely vulnerable to pests, infection, or environmental change. Monoculture runs counter to the fundamental biological principle of maximal diversity as the key to adaptability, and we have learned that at great cost in agriculture, forestry, and fisheries. In spite of this insight, we continue to ignore the importance of maximizing diversity and thus sacrifice long-term resilience and sustainability for the sake of immediate human needs. And we are drastically reducing diversity, not just in the natural world but in human societies around the world. A single notion of economics and development has been spread throughout the globe as nations ignore the 1933 warning of the father of the International Monetary Fund and World Bank, John Maynard Keynes: I sympathize with those who would minimize rather than maximize economic entanglement between nations. Ideas, knowledge, art, hospitality, travel—these are the things which should of their nature be international. But let goods be homespun whenever it is reasonable and conveniently possible; and above all, let finance be primarily national (Keynes 1933). The economic monoculture that is pursued by every government in the world makes no ecological sense. Most economists externalize the very support systems of life—air, ozone layer, topsoil, water, and biodiversity itself. Small wonder, then, that it is cheaper for a Toronto restaurant-owner to serve lamb imported from New Zealand than mutton purchased from a farm 40 km north. Even though we live in a finite world, economics is predicated on the notion that it is not only possible but necessary to strive for steady, endless growth. It is suicidal for a single species that is increasing in numbers exponentially and that has already co-opted 40% of the net primary productivity (NPP) of the planet to demand further economic growth that will come from increasing its share of the NPP (Vitousek and others 1986). The destructive consequences of this mindless fixation on economic growth as society's most important goal are exacerbated by the measurements of economic success. Any transaction of goods and services resulting in an exchange of money registers as an increase in GDP, whether it is the purchase of weapons to counter high crime rates, hospital and funeral costs of homicides and cigarette-smoking, or cleaning up after an oil or chemical spill. In the GDP, whether money is spent to correct social or ecological damage is irrelevant. As shown by the organization Redefining Progress, which uses an economic indicator that subtracts for such costs, the per capita GDP has more than doubled since 1950, but the Genuine Progress Indicator (GPI) rose slowly to a peak about 1970 and has been declining ever since (Cobb and others 1994).

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Page 19 The global economy that Keynes warned about is dominated by speculators and transnational corporations (TNCs) that are no longer tied to local populations or ecosystems. The current attempt by the OECD to gain passage of the Multilateral Agreement on Investments will open each country to the depredations of the TNCs while freeing them of responsibility to provide jobs or income for local communities or environmental protection of local ecosystems. Maximizing profit appears to be sufficient rationale for globalization of markets and economies. Where once currency represented something tangible, increasingly it stands for itself. Today, we can buy money, sell money, and make more money without adding anything of value to society or the planet. The $1.3 trillion in daily currency speculation is bigger than most government treasuries, as we see when governments attempt without success to stop the fall in the franc and peso. This global currency flows electronically across all borders and grows far more quickly than real things. So now, as companies diversify, they can deplete one sector and then move to the remaining areas of income. The great temperate rain forests of British Columbia add “fiber” at the rate of 2–3% per year. Obviously, by cutting only 2% or 3% of the trees each year, forest companies could remove the equivalent of the entire forest in 35 or 23 years, respectively, and still have the entire forest left. But it makes no economic “sense” to take only 2% or 3% per year if a company can make 8% or 9% on its investment by clear-cutting an entire forest and putting the money in the bank. If the money is invested in forests in other countries, it might be possible to make far more; and when the forests are gone, the money can be put into fish; and when they are gone, the money can go into biotechnology or computers. So the economics drive a company to maximize profit without regard to long-term sustainability. Reconnecting Ourselves by Setting the Bottom Line Today, governments around the world pursue a “bottom line” that is driven by an economy that is disconnected from the real world and fundamentally destructive of local communities and local ecosystems. Global competitiveness, efficiency, debt, deficit, and profit are buzzwords defining bottom lines. But it is a bottom line that omits the fundamental basic needs of all human societies. To see what our real nonnegotiable needs are, we must first recognize and surmount the barriers to the interconnections between our activities and the rest of the world that nurtures us. The first level of human need is defined by our biology—as animals, we have fundamental requirements, and failure to meet them adequately results in death or truncated lives. These needs are so important that our bodies have a multitude of safety devices to ensure that they are met. I am speaking, of course, of our need for clean air, clean water, clean soil, and clean energy, all of which are delivered by the planet's collective biodiversity. We need only hold our breath for 1 minute to recognize the life-giving nature of air. Deprived of air for 3 minutes, we are permanently brain-damaged; after 5 minutes, we die. From the moment of our birth to the instant of our death, we need air. We take each breath

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Page 104 Countryside Biogeography and the Provision of Ecosystem Services Gretchen C. Daily Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020 Humanity has become a dominant force on Earth, altering important characteristics of the atmosphere, oceans, and terrestrial systems. One of the many consequences of these alterations is the extinction of populations and species, which is projected to drive biodiversity to its lowest level since humanity came into being (Ehrlich and Ehrlich 1981; Wilson 1992). A crucial set of policy questions is when, where, and how to direct societal activities to soften or reverse their effect on biodiversity. In addressing these questions, one is immediately confronted with a set of trade-offs in the allocation of resources (such as land and water) to competing uses, to competing individuals and groups of people, and ultimately to competing value systems. These tradeoffs are becoming increasingly vexing from both ethical and practical perspectives. They involve our most important ideals (such as ensuring a prosperous future for our children), our oldest tensions (such as between individual and societal interests), and sometimes our bloodiest tendencies (such as using genocide as a convenient way of gaining control over resources). Society is poorly equipped to handle these tradeoffs, and they are appearing everywhere; the well-being of current and future generations hinges on how the tradeoffs are dealt with. The short-term benefits of alteration of habitats, the primary cause of loss of biodiversity, are typically clear and allow relatively small groups of immediate beneficiaries to exert great influence on the political process in favor of short-term exploitation. In contrast, the arguments for conservation tend to be diverse and difficult to measure, and the benefits of any single decision about conservation are

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Page 105 diffused over very large numbers of people. The arguments for conservation typically are drawn from any of four distinct lines of reasoning: ethical, aesthetic, direct economic, and indirect economic (Heywood 1995; Hughes and others 2000; Ehrlich and Ehrlich 1992). Ethical reasoning involves the conviction that, as the dominant species on the planet, humanity has the responsibility of stewardship toward “The Creation,” its only known living companions in the universe. This moral responsibility exists independent of the perceived value of nonhuman organisms to human well-being. The other three classes of argument rest on the benefits that humanity derives from other organisms, which I collectively refer to here as “ecosystem services.” The reasons for stemming the loss of biodiversity thus range in character from the intangible, the spiritual and philosophical, to the purely anthropocentric and pragmatic (for a nice overview, see Goulder and Kennedy 1997). One might say they span the spectrum from things that make life worth living to things that make life possible at all. Clearly, both ends of the spectrum are important, although the significance ascribed to each varies considerably with social context and understanding. Lack of public understanding of societal dependence on natural ecosystems is a major hindrance to the implementation of policies needed to bring the human economy into balance with the capacity of Earth's life-support systems to sustain it. The purpose of this paper is to explain this dependence briefly, to describe how recognition of it can help resolve the tradeoffs that society now faces, and to indicate where society could invest profitably in broadening and deepening the scientific understanding of ecosystem services. First, I briefly characterize ecosystem services in biophysical and economic terms. Then, I indicate how the concept provides a framework that, if supported with appropriate institutions and policies, allows us to incorporate ecosystem-service values into decision-making. Finally, I turn to a key underlying biological issue: the capacity of human-dominated landscapes to support biodiversity and sustain ecosystem services. My emphasis throughout is on the anthropocentric and pragmatic. Life on the Moon. Society derives a wide array of life-support benefits from biodiversity and the natural ecosystems within which it exists. These benefits are captured in the term “ecosystem services”, the conditions and processes through which natural ecosystems, and the species that are a part of them, sustain and fulfill human life (Daily 1997; Holdren and Ehrlich 1974). These services include the production of ecosystem goods, such as seafood, timber, forage, and many pharmaceuticals, which represent an important and familiar part of the economy. Perhaps the easiest way to appreciate the importance of biodiversity in supplying life-support goods and services is by way of a thought experiment that removes the familiar backdrop of Earth. Imagine trying to set up a happy life on the moon. Assume for the sake of argument that the moon miraculously already had some of the basic conditions for supporting human life, such as an atmosphere, a climate, and a physical soil structure similar to those on Earth. After packing one's

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Page 106 possessions and coaxing one's family and friends into coming along, the big question would be, Which of Earth's millions of species would be needed to make the sterile moonscape habitable? One could choose first from among all the species used directly for food, drink, spices, fiber, timber, pharmaceuticals, and industrial products, such as waxes, rubber, and oils. Even if one were selective, this list could amount to hundreds or even thousands of species. And one would not have begun considering the species needed to support those used directly: the bacteria, fungi, and invertebrates that recycle wastes and help make soil fertile; the insects, bats, and birds that pollinate flowers; and the herbaceous plants, shrubs, and trees that hold soil in place, nourish animals, and help control the gaseous composition of the atmosphere that influences Earth's climate. No one knows exactly how many or which combinations of species would be required to support human life. So, rather than listing individual species, one would have to list instead the life-support services required by the lunar colony and try to choose groups of species able to perform them. A partial list of such services includes the following (Daily 1997): • production of a wide variety of ecosystem goods; • purification of air and water; • mitigation of flood and drought; • detoxification and decomposition of wastes and cycling of nutrients; • generation and preservation of soils and renewal of their fertility; • pollination of crops and natural vegetation; • dispersal of seeds; • control of the vast majority of agricultural pests; • maintenance of biodiversity; • protection from the sun's harmful ultraviolet rays; • partial stabilization of climate; • moderation of weather extremes and their effects; and • provision of aesthetic beauty and intellectual stimulation that lift the human spirit. The closest attempt to carry out this experiment here on Earth was the first Biosphere 2 “mission” (Cohen and Tilman 1996). A facility was constructed on 3.15 acres in Arizona that sealed off its inhabitants as much as possible from the outside world; eight people were meant to live inside for 2 years without the transfer of materials in or out. The experimenters had to decide which species to use to populate the closed ecosystem. They moved in tons of soil (with its huge abundance and variety of little-known fungi, arthropods, worms, and microorganisms), added numerous other animals and plants, and fueled the system with sunlight (through transparent walls) and electricity (at an annual cost of about $1 million). Biosphere 2 featured agricultural land and elements of a variety of natural ecosystems, such as forest, savanna, desert, and even a miniature ocean. In spite of an investment of $200 million in the design, construction, and operation of this model Earth, it proved impossible to supply the material and physical needs of the eight “Biospherians” for the intended stay. Many unexpected and

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Page 107 unpleasant problems arose, including a drop in the concentration of oxygen from 21% to 14%, a level normally found at an elevation of 17,500 ft; skyrocketing concentrations of carbon dioxide with large daily and seasonal fluctuations; high concentrations of nitrous oxide to the point where brain functioning can be impaired; extinction of 19 of 25 vertebrate species; extinction of all pollinators (thereby dooming most of the plant species to eventual extinction); population explosions of aggressive vines and crazy ants; and failure of water-purification systems. The basic conclusion from this experiment is that there is no demonstrated alternative to maintaining the viability of “Biosphere 1,” Earth (Cohen and Tilman 1996). Ecosystem services operate on such a grand scale and in such intricate and little-explored ways that most could not be replaced by technological means (Ehrlich and Mooney 1983). They existed for millions or billions of years before humanity evolved, making them easy to take for granted and hard to imagine disrupting beyond repair. Yet escalating effects of human activities on natural ecosystems now imperil the delivery of these services. The primary threats are changes in the uses of lands, causing loss of biodiversity and facilitating biotic invasion, and synergisms of these with alteration of biogeochemical cycles, release of toxic substances, possible rapid change of climate, and depletion of stratospheric ozone (Daily 1997b). Management of Natural Capital Maintaining Earth as a suitable habitat for Homo sapiens will require society to begin to recognize natural ecosystems and their biodiversity as capital assets, which, if properly managed, will yield a flow of benefits over time. Relative to physical capital (buildings, equipment, and so on), human capital (skills, knowledge, health, and so on, embodied in the labor force), and financial capital, natural capital is poorly understood, little valued, scarcely monitored, and undergoing rapid depletion. Sustainable management of ecosystem services will require a systematic characterization of the services, in biophysical, economic, and other terms along with the development of financial mechanisms and policy institutions to provide the means of monitoring and safeguarding them. Characterization involves an explicit cataloging of important services on a variety of scales. In other words, which ecosystems supply what services? For a given location, which are supplied locally, which are imported, and which are exported? Characterization also involves finding answers to other questions (Costanza and Folke 1997; Daily 1997c; Holdren 1991), such as, what is the effect of alternative human activities on the supply of services? The administration of New York City first considered replacing its natural water-purification system (the Catskill Mountains) with a filtration plant but found that it would cost an estimated $6–8 billion in capital plus $300 million per year to operate. The high costs prompted investigation of an alternative solution, namely restoring and safeguarding the natural purification services of the Catskills. That would involve purchasing land in and around the watershed to protect it and subsidizing several changes on privately owned land: upgrading sewage-treat-

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Page 108 ment plants; improving practices on dairy farms and undertaking “environmentally sound” economic development. The total cost of this option was estimated at about $1.5 billion (Revkin 1997). Thus, New York City had a choice of investing in $6–8 billion in physical capital or $1.5 billion in natural capital. It chose the latter option, raising an environmental bond issue to fund its implementation. This financial mechanism captured the important economic and public-health values of a natural asset (the watershed) and distributed them to those assuming the responsibilities of stewardship for the asset and its services. The Catskills supply many other valuable services, such as control of flooding, sequestration of carbon, conservation of biodiversity, and, perhaps above all, beauty, serenity, and spiritual inspiration. Moreover, these services benefit others besides consumers of water in New York City. It would be absurd to try to express the full value of the ecosystem services provided by the Catskills in dollars. In this case, fortunately, there was no reason to try: even a lower estimate of the value of the natural asset was sufficient to induce adopting a policy of conservation. The challenge is to extend this model to other geographic locations and to other services. The US Environmental Protection Agency recently estimated that treating, storing, and delivering safe drinking water to the United States without taking this approach would require an investment in physical capital of $138.4 billion over the next 20 years. More than 140 municipalities in the United States now are considering watershed protection, an option that aligns market forces with the environment, as a more cost-effective option than building artificial treatment facilities (The Trust for the Public Land 1997). Indeed, interest is growing worldwide in adopting watershed conservation. Rio de Janeiro and Buenos Aires, for example, are investigating this option; both have highly threatened watersheds of enormous biotic value (Chichilnisky and Heal 1998). Extending this model to other services requires that an ecosystem meet two conditions. First, it must supply at least one good or service to which a commercial value can be attached. Second, some of that value must be appropriable by the steward of the ecosystem (Chichilnisky and Heal 1998). Public goods and services are difficult to privatize: if provided for one, they are provided for all, so their providers typically cannot appropriate all the value of the good or service. Natural water purification is a public service, but access to the resulting high-quality water is excludable; thus, the case of a watershed works by bundling a public service with a private good. Private capital could be mobilized in this cause to the benefit of both individual investors and society at large (Chichilnisky and Heal 1998). In principle, this approach could be made to work for other ecosystem goods and services, such as for realizing and safeguarding biodiversity, ecotourism, and carbon-sequestration values. With appropriate institutional support (such as that needed for the management of common property resources), mechanisms for safeguarding sources of flood control, pollination, and pest-control services also may be developed. This is an important subject for further interdisciplinary investigation by persons from academe, government, and the private sector.

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Page 109 Countryside Biogeography Attaining the ultimate goal of sustainably managing natural capital will require a deeper understanding of the relative effects of alternative activities on biodiversity and ecosystem services. A key question is, Where do critical thresholds lie in the relationships between the condition and extent of an ecosystem and the quality of the services that it supplies? Let us explore this issue from the perspective of the modification of ecosystems by agricultural activities. Food production is arguably humanity's most important activity. It is also the most important proximate cause of the loss of biodiversity worldwide, involving major direct and indirect effects, including conversion of natural habitat to agricultural use, facilitation of biotic invasion through trade (thereby increasing the rate of introduction of exotic species) and alteration of habitat (thereby increasing the susceptibility of native communities to invasion), and application of chemical fertilizers and pesticides. In the face of such effects, the fates of organisms that once made their homes in unbroken expanses of natural habitat range along a broad continuum. At one end is the decline of population to local and eventually global extinction; at the other end is expansion into human-controlled landscapes. Biologists have paid considerable attention to the status of the biotas of fragments of natural habitat, such as forest patches, and comparably little attention (outside the context of pest management) to the organisms that occupy the highly disturbed matrix in which those fragments occur. One reason for this emphasis is undoubtedly the crisis nature of extinction: given the justified panic to save remaining natural habitat, it is taking some time to appreciate a complementary opportunity, namely, to enhance the hospitability of agricultural landscapes for biodiversity. The emphasis traces to other factors, including the prominence of the theories of island biogeography and the island paradigm in conservation biology; the assumption that a very small fraction of species is capable of persisting outside of “islands” of natural habitat, that is, in human-controlled habitats; and the frequent (although often subconscious) projection of disdain for humanity's destruction of natural habitat onto the organisms that profit from it. The organisms that can take advantage of countryside, rural and suburban landscapes devoted primarily to human activities, deserve more attention for a series of reasons. First, it is unlikely that many large, relatively undisturbed tracts of natural habitat will remain in the face of projected growth in the size, food needs, and environmental effects of the human population. Second, the potential for conserving many species might rest on preserving or enhancing some aspects of rural landscapes that contain remnants of native habitat in lieu of protecting large tracts of undisturbed habitat, which is generally much less feasible socioeconomically. Third, the supply of some important ecosystem services—such as pest control, pollination, and water purification—will depend in many instances on the biodiversity that occurs locally, in the vicinity of human habitation, in countryside habitats. Finally, a growing interest in restoration also will require comparing the conservation value of alternative sites for the establishment and succession of desired community assemblages.

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Page 110 Countryside biogeography is the study of the diversity, abundance, conservation, and restoration of biodiversity in rural and other human-dominated landscapes. Broad issues in this area pertain to the future course, societal consequences, and appropriate policy responses to the mass extinction currently under way. They include the following sorts of questions. • What is the relationship between levels of agricultural intensification and biodiversity in countryside landscapes? Measures of agricultural intensification include the frequency distribution of clearing sizes, the ratio of clearing to hedgerow areas, the spatial configuration and relative coverage of native and human-dominated habitats within the countryside landscape, the diversity of crops under cultivation, modification of the hydrological cycle, and the levels and types of chemical fertilizers and pesticides applied. • Which species traits confer an advantage for survival in the face of tropical deforestation and other major alterations of habitat? • Are these traits distributed randomly across taxa, or are some groups of organisms especially resistant and others especially prone to extinction? In other words, will the current episode of extinction nip off the buds of the evolutionary tree of life relatively uniformly, or will it eliminate some major limbs, dramatically reshaping the future diversity and evolution of life? • Can simple mathematical theory be developed to predict patterns of persistence of biodiversity in countryside landscapes? • How accurately can patterns of biodiversity in countryside habitats be predicted on the basis of remotely sensed information on land use (for example, with images from satellites)? • How effectively can countryside biotas perform ecosystem services? • What practical measures can be taken to enhance the capacity of countryside habitats to sustain biodiversity and ecosystem services as well as human activities? This is not the place for a comprehensive review of work addressing those issues. I offer instead a few illustrative findings to date: • In Europe, more than 50% of the land area with high conservation value is under low-intensity farming. Examples of these habitat types include blanket bog, northern Atlantic wet heath, lowland hay meadow, heather moorlands, wood pasture, alpine pasture, and nonirrigated cereal steppe (Bignal and McCracken 1996). Intensification of farming practices in recent decades has resulted in declining populations of many species of birds throughout Europe. For instance, nine of the 11 species of waders listed in the Red Data Book that occur in Sweden are seriously threatened by changes in farming practices there (Johansson and Blomqvist 1996). • Recent studies are beginning to illuminate the strength and type of biotic control over the functioning of ecosystems (Chapin and others 1997). Greater richness of species can enhance the stability of the ecosystem. In species-poor plots of grassland in Minnesota, for example, a severe drought caused a reduction

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Page 111 in productivity of more than 90% from predrought levels, whereas productivity in species-rich plots was reduced by 50% (Tilman 1994). Alterations in habitat that change the functional diversity and composition of plant species appear especially likely to have major effects on various properties of ecosystems (Hooper and Vitousek 1997; Tilman and others 1997). • In the vicinity of Las Cruces in southern Costa Rica, a significant fraction of the native avian species appear to be persisting, at least temporarily, in open countryside habitats in a mixed-agricultural landscape that retains 27% of its once-continuous forest cover. Of possible original totals in the 33 species of birds under consideration, it appears that 1–9% have become extinct locally, 50–54% are restricted to habitats of forested countryside, and 36–40% occur in habitats of open countryside that are as far as 6 km from the nearest large tracts (at least 200 hectares) of forest (Daily and others in review). • Some systems of cultivation used in coffee production appear to have high potential for conserving birds and other elements of the native biota. Systems of cultivation that use shade trees, plantations with tall canopy cover, diverse stratification, little pruning, and low levels of insecticides are especially rich in birds, including both resident and neotropical migrant species (Greenberg and others 1997). Strikingly high abundances of arthropods and richness of species have also been found. For example, fogging of shade trees with pyrethrins in a Costa Rican coffee plantation in formerly upland-rainforest habitat yielded a richness of coleopteran and hymenopteran species comparable with that of samples from trees in upland rainforests in Peru and Brazil (Perfecto and others 1996). • Nocturnality might confer an advantage of dispersal and possibly of survival in the face of tropical deforestation. Surveys of the diversity of diurnal birds and butterflies and nocturnal beetles and moths in forested patches reveal the classic island biogeographic pattern for birds and butterflies (in other words, fewer in smaller patches) but similarly high diversities of moths and beetles among forested patches of all sizes (0.1–225 hectares). A possible mechanism explaining this apparent advantage is that typically the movement of nocturnal species occurs when the conditions of thermal, humidity, and solar radiation are similar between native forest and cleared areas; during the day, the hot, dry, and bright conditions in open areas might impede dispersal seriously for many organisms (Daily and Ehrlich 1996). Ideally, further effort in empirical and theoretical research on issues of countryside biogeography eventually will allow us to predict patterns of biodiversity in human-dominated landscapes worldwide (White and others 1997). This would be an important step toward characterizing and monitoring the effects of humans on ecosystems and the services they supply. Conclusions The human population and its standards of living are maintained by a steady depletion of natural capital assets, including renewable-resource stocks and waste sinks that, if they were safeguarded, could sustain a flow of ecosystem goods and

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Page 112 services through time. In our collective behavior, there is little recognition or systematic accounting, let alone nurturing, of these critical capital assets. Tremendous payoff could result from further research on managing Earth's life-support systems. Such research should be oriented toward developing the following: • a broader and deeper understanding of the functioning of Earth's life-support systems and the effects of humanity on them, especially in countryside habitats; • systematic accounting and monitoring of the condition of these systems; • ways of quantifying the importance of ecosystems at the margin, from biophysical, economic, and cultural (aesthetic and spiritual) perspectives, that is, ways of determining, for instance, how much importance should be attached to the preservation or destruction of the next unit of habitat; • ways of incorporating these values into a framework for decision-making; and • ways of creating appropriate institutions and policies to allow the individuals or societies that safeguard life-support systems for the public good to realize the value of their stewardship. In the market-driven culture that prevails today, the concept of ecosystem services offers a new way to approach actions of conservation by confronting market forces on their own terms. This concept has promise because it integrates biophysical and social dimensions of managing the biosphere; it offers rational, practical solutions to tradeoffs in allocation of resources to competing uses and people; and it is adaptable to different economic and cultural circumstances. Similarly, countryside biogeography can reveal new strategies for preserving biodiversity and ecosystem services in the context of some of humanity's most important activities. Nevertheless, these frameworks are just two tools to complement the many others required for protecting biodiversity (Raven 1990; Raven and Wilson 1992). In our quest to safeguard the systems that make life possible, it is critical that we not lose sight of what makes life worth living. Acknowledgments I am grateful for insightful comments from Scott Daily, Michael Dalton, Paul Ehrlich, Geoffrey Heal, and Jennifer Hughes. This work was supported by the generosity of Peter and Helen Bing, the Pew Charitable Trusts, and the Winslow Foundation. References Bignal EM, McCracken DI. 1996. Low-intensity fanning systems in the conservation of the countryside. J Appl Ecol 33:413–24. Chapin FS III, Walker BH, Hobbs RJ, Hooper DU, Lawton JH, Sala OE, Tilman D. 1997. Biotic control over the functioning of ecosystems. Science 277:500–4. Chichilnisky G, Heal G. Forthcoming. Securitizing the biosphere. Nature. Chichilnisky G, Heal G. 1998. Economic returns from the biosphere. Nature 391:629–30 Cohen JE, Tilman D. 1996. Biosphere 2 and biodiversity: the lessons so far. Science 274:1150–1.

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