The category of North American animals that has suffered the most acute decline at human hands in recent generations appears to be freshwater mussels, which once populated river bottoms in great abundance and variety. At the end of the nineteenth century Illinois fancied itself the button capital of the world due to the fertility of its mussel beds, especially in the Illinois and Mississippi rivers. Harvested there by the shipload the mussels were stamped into buttons to meet the needs of much of the world. Mussels, however, are largely stationary creatures. Once a mussel finds a place to live it secures itself there and pretty much stays put. Thereafter it is at the mercy of changes in the river, in the fluctuating water flow, in the chemicals the river contains and, most of all, in the silt load the river carries. Human uses of the rivers—particularly dredging to facilitate boat and barge traffic—unleash massive amounts of silt that clog, cover, and kill many mussel species. Uses of surrounding lands have also taken a heavy toll. Eroded soil runs off nearby fields. Artificial drainage efforts accelerate water flows during parts of the year, leading to deeper channels, streambank collapses, and water-quality declines. For many environmentalists the disappearance of mussels—many species of them exterminated, many others imperiled—is both troubling in and of itself and emblematic of the ecological deterioration of aquatic systems generally. The decline of mussels is a serious environmental problem.
This claim of deterioration, though, has not gone unchallenged. Interest groups that use the river intensively for travel or waste disposal sometimes question whether the loss of obscure mussel species really is much of a problem. The mussels serve no particular human need, certainly no need that is not easily met in other ways. Many mussels are adapted to live in peculiar aquatic settings that are disappearing and they are apparently not needed to perform any ecological function elsewhere. Attached to river bottoms, mussels go unseen by almost everyone. Indeed, few people know of them, which means few would miss them once they are gone. What exactly is there to worry about?
It is useful to take this question seriously, not just because it expresses a point of view held by many, but because it goes to the center of the whole issue of misusing nature. When we say people are degrading nature we judge their conduct negatively We are not merely describing action; we are evaluating it normatively and finding it wrong, immoral, or at least inexpedient, But on what basis is such a judgment made and who picks the standard to make it?
It is culturally revealing that most people, if asked, would have trouble composing a definition of an environmental problem. Nearly everyone could readily offer an example or two, a matter of pollution, usually, or toxic contamination. But it is harder to craft a categorical definition. It doesn’t seem sensible to say that an environmental problem is simply a condition in nature we don’t like or want—rain on a day we’d like to picnic, for instance. That seems more like an environmental condition that we work around. We could say that a shortage of water in the desert is an environmental problem, but that too seems more like a description of nature. We can lament the lack of water and want more of it; a water shortage can cause hardship, even death. Yet somehow that kind of situation seems distinguishable from the problems commonly viewed as environmental.
One way to define environmental problem, a definition with quite useful implications, is simply this: An environmental problem is a human activity that in some way involves the misuse of nature. This definition implicitly distinguishes between two types of natural conditions that we might dislike, one due to human activities, the other arising from the natural traits of a place. It reserves the term “environmental problem” for those conditions that humans have brought about, or more exactly it focuses attention on the human action that causes the condition and describes that behavior itself as the problem.
This definition helps in two ways. First, it draws attention to the human activity itself and makes clear that the adverse judgment implicit in the term “environmental problem” is a judgment on some human activity, not a complaint that nature itself is somehow second-rate. Nature is what it is and it operates in some ways rather than others. We can make the planet better from our perspective and sometimes have; we needn’t accept nature as it is. But it helps to get clear in our minds that some of our changes to nature are bad rather than good, and we need a term that applies to such misdirected actions.
A second benefit of the definition is one that might seem like a deficiency, and that is the inherent ambiguity or even vacuity of the term “misuse.” The term is plainly judgmental; it refers to a wrongful act. But without getting clear on the meaning of “misuse,” the definition of environmental problem is half empty. Does it help to define an uncertain term by using another term, also uncertain?
The benefit that arises here comes precisely because the term “misuse” or “abuse” calls out for clarification. As it does so the definition highlights that we can’t point a finger at some human-caused landscape change and slap on the label “environmental problem”—the loss of mussels in a river, for instance—without evaluating the change under a normative standard that distinguishes legitimate use from abuse. And we can’t do that until we’ve crafted such a standard. Quickly, then, we get to the task at hand, to develop such a standard or test, a task that gains in complexity the more one engages it.
We can approach this point in a related way that highlights our rather poor collective efforts at crafting a usable test. We might imagine being invited to drive the roads in a local region and to study its land uses. Upon returning we are asked: Are the people of the region putting the lands to good use? A sensible answer would begin with a confession: the drive through the region has hardly yielded enough factual information to inform a judgment. Far more data would be needed simply to know what people were doing in the place, much less to trace the ecological, economic, and social implications. A sensible answer would also confess, though, that even possessed of full factual knowledge it isn’t possible to evaluate the goodness of land use without a definition of goodness. Without one, facts are just facts. No amount of facts, no quantity of scientific data, can produce a judgment on land uses, good or otherwise. As already stressed, evaluation requires normative thinking. Fact collection and assessment, no matter how essential and carefully done, contain no normative content.
To live decently on land we must change the natural world, just as all other life forms change it. In the instance of the slow-moving rivers of the American Midwest, once so rich in mussels, probably no species altered them prior to the industrial age more than the beaver (Castor canadensis). This large rodent constructed so many dams on regional streams that something like 25 percent of all waterway miles in the Mississippi River basin were once backed up by their structural engineering. The resulting ecological consequences were immense. Habitat improved greatly for many species while taking a turn for the worse for many others. For beavers, the dams made the world better.
Our challenge in living on land rather evidently includes the need to come up with a sound way to distinguish use from abuse. Only with one can we judge whether a change to nature is an environmental ill. To date we haven’t done particularly well at this foundational task. Indeed, although the challenge once thus posed is plainly important, it strikes most people as novel, a matter never before presented in quite this way.
Pressed for a standard of evaluation many people would talk in terms of “sustainability”—a popular term that thrives despite sharp criticism. We misuse land when our activities are not sustainable—that’s the likely response. The term is helpful enough in that it draws attention to the long term and reflects concern for the plight of future generations. Beyond that, though, the term lacks much content. What exactly are we sustaining? Not, one hopes, longstanding modes of degradation. Many of the resources we use are nonrenewable in anything close to human timeframes; any consumption of them would seem unsustainable. Should we stop drawing down such resources given that we can’t sustain any level of use forever? All human activities not only change nature but trigger ecological ripple effects that can spread widely. Those ecological changes, in turn, will require responsive adjustments in future human activities. Given ongoing ecological change we can’t continue living precisely as we have in the past—we can’t sustain our past activities—if only because the surrounding natural world is changing and we need to adapt to it.
Many proponents of sustainability have offered more precise definitions, making reasonably clear what needs sustaining. A problem with them is that they differ widely, so much so that sustainability—as one of its much-cited deficiencies—can seem to mean all things to all people. Better-considered definitions tend to be phrased not in terms of particular human activities directly, but instead in terms of the conditions of the surrounding natural world—its ecological functioning, quite often, or the types and numbers of wild species that inhabit an area. These are the things we want to sustain. But if we know the ecological terms that we want to respect and promote, then shouldn’t the operative standard—the test used to distinguish use from abuse—be phrased in terms of those ecological conditions, rather than in the vague, incomplete language of sustainability?
More will be said about an overall normative standard, beginning in chapter 5. What needs clarity at this stage is how we have stumbled along for years with little direct thought about how we might distinguish use from abuse, filling the intellectual gap with the term “sustainability” (or a variant such as “sustainable development”) that, when pressed, lacks much content when its varied usages are all considered.
Our poor performance at this line-drawing task is significant, for it is rooted in more than simple inattentiveness and bad politics. The failing is linked to our tendency to want science to answer policy questions for us and, going further, to a too-common misunderstanding about what science is and what it is not. It is rooted also in our tendency to think that questions of morality should largely be left to individuals to decide as they see fit so long as they respect the public order. In the case of rural land, for instance, we are prone to think that landowners themselves should decide how they will use their lands so long as they avoid overt harm to neighbors. The implication here is that land use is private rather than public business and that the morality of using nature—the moral challenge of distinguishing use from abuse—should be made at the individual level, not higher up. Finally and similarly, our failure to address this issue squarely reflects antigovernment sentiment mixed with longstanding liberal claims that government should remain neutral among competing visions of the good, allowing individuals maximum freedom to act as they would. These are powerful cultural leanings that go far toward explaining our collective failure to think clearly about the use-abuse line. They also help explain why so many people push away evidence of environmental ills, even when scientifically well attested, and why we resist even environmental reforms that would bring economic growth.
This criticism of sloppy thinking is not limited to people who resist claims of environmental ills. It often seems characteristic, too, of people who pay attention to problems, and even to the subset of such people, activists, who step forward to help slow or deflect the downward slide. Here the problem perhaps comes simply from a sense that good intentions and a basic sense of direction provide enough guidance for the conservation work that needs doing; more serious thought, particularly cultural criticism, is unneeded. The problem also appears linked to a tendency to focus on rhetoric that makes sense to audiences where they are in the present, not rhetoric that pushes for fundamental long-term change.
Shallow thinking among nature’s defenders too often shows up in their efforts to resist development projects that would significantly alter natural systems. A finger is pointed at an unwanted alteration—a shopping mall, a new road, a reservoir, or waste dump—and its expected ecological consequences are promptly criticized as hurtful. As for measuring the anticipated harm of a challenged project, the familiar practice is to begin with some natural condition as the starting point for comparison. Here is the anticipated human-caused change to the natural system, and all of the change will be harmful; that’s the outgoing message, implied or expressed. Of course activists typically expect to bargain and accommodate, they expect some ecological change to take place. They view themselves, that is, as a needed counterbalance to powerful economic forces and the more effectively they push against them the more degradation they might contain. There can be, to be sure, good sense to this approach tactically and the motivation is both easy to appreciate and praiseworthy. But the beginning point is nonetheless often a blanket—if implicit—condemnation of all landscape change. The measuring standard, the beginning point, is a landscape (or a particular part of it) essentially unaltered by people. Alteration is inherently bad, and the less of it the better. When green advocates take this approach they too have avoided the hard work of distinguishing between use and abuse. Meanwhile, as they oppose intensive human land uses they open themselves to claims of misanthropy, of caring about nature and not about people.
In fairness, a firm-line strategic approach toward further invasions of natural areas can sometimes make considerable sense, particularly in landscapes that are already much altered. It can make particular sense when the conservation effort aims to preserve a rare piece of wildness in a landscape that is already being hard pressed to serve human needs. For critics of such nature protection, the antidevelopment approach can seem unduly stark and one-sided: The complaining green groups, it seems, simply want to preserve everything. But in significantly altered landscapes—that is, in most places where people live and work—such a firm-line policy appears one-sided (misanthropic) only when the assessment uses the current, altered state of the landscape as the point of beginning for tradeoffs. If instead the beginning point of assessment is set back in time, if the assessment includes landscape changes already made, then the bottom line can look far different. The proportion of land being protected by green interests becomes far less; the corresponding proportion devoted to direct human needs is far higher.
There are landscape settings, then, in which opposition to further change might well make good sense, places where any further development would go beyond proper use to become abusive. Even so, though, the environmental side in such clashes would do better to put forward a more thoughtful stance on how we ought to distinguish between the two. It would do better to articulate where it would draw the line between use and abuse. Lacking such a stance, the easy tendency for activists is, as noted, simply to label all change abusive. If all is abuse then humans have no rightful role on the planet and the fewer of them the better. No major environmental organization, we should note, takes this stance or anything remotely like it. But lacking a clear message on use and abuse their public stances are easy to misinterpret and their own judgments can get sloppy.
This brings us back to the continuing, severe decline of mussels in the usually slow-moving rivers of the American Midwest. Defenders of them would like to save all mussel species, ideally in something close to their original distributions and population numbers. They know full well that this cannot and will not happen. Their hope is thus an ideal from which compromises will be made—huge compromises in all likelihood, given the enormous political power of agriculture and other river users. But by taking this stance mussel-defenders are, in effect, using wilderness-like conditions as their measure of the proper use of nature, which is to say they would, by implication, limit humans to uses of nature that yield little or no ecological change. Such a policy stance doesn’t really help citizens and communities think through the issues clearly and to generate visions of good land use at large spatial scales.
In the case of mussels on river bottoms, it might well be that humans could thrive on surrounding land while slowly returning mussel beds to ecological health (albeit without the species that are gone). Such an effort would require major changes in current land- and river-use activities, probably ending all commercial barge traffic on the rivers, removal of the many locks and dams, and significant reductions in the artificial drainage of surrounding lands. But these various changes might over time in fact yield net economic gains for the nation, not losses (as commonly assumed), given the high costs of maintaining the artificial waterways (dredging, levee building, and lock-and-dam maintenance), given the availability of alternatives in transport (rail), and given the sizeable economic benefits of healthy rivers. Most efforts to protect or enhance nature do bring about sizeable economic gains overall (albeit with winners and losers), sometimes sizeable enough so that the resulting environmental benefits end up costing nothing. Even in such instances, though, it clouds thinking to press wilderness-like conditions as the appropriate normative goal, or as the baseline for measuring abusive change, implying that all human alterations to nature are wrongful.
The call for preservation needs to be presented in other, more thoughtful terms. Preservation of part of a landscape needs to be situated intellectually and morally within a fuller vision of people living well on land in ways that can long endure.
To sum up, we have not done well thinking clearly about how best to distinguish use from abuse. This shortcoming by all appearances is widespread (though with scattered exceptions), including among many environmental activists. It is important not to push this criticism of the environmental effort too hard, for it applies only in selected settings. Many activists, for instance, labor to improve the healthfulness of food systems, fully agreeing that we need to use land intensively to produce food. In such settings, a wilderness-type vision plays no role. Other activists support sound forestry management that uses mixed-species, mixed-aged, selective-harvesting techniques to yield continuous flows of high-quality timber while also providing good forest habitat for wildlife; what they oppose is heavy-chemical monocultural tree farming. Still others labor to restore habitat for salmon and other fish precisely so that the fish stocks can once again become important wild food sources for people along the river. Nonetheless, the environmental movement as a whole has not presented to the public anything much like a clear definition of ecological degradation, tied to a vision of good land use at the landscape scale. It needs to do so.
This failure to think clearly about use and abuse also crops up in the work of ecological restoration. Restoration typically carries a positive connotation but it is an ideal or activity that is weakened by the same kind of vagueness as sustainability. In practice the restoration ideal refers not usually to a desired land-use endpoint but instead simply to a desire to move backward in time, a desire to undo changes that have already taken place. A historic building is restored when it is returned to some prior physical condition. Necessarily building restorers need to decide how far back in time to go: To the point when the building was first completed? To some later point of occupancy, after some change to the original building had taken place? Land restoration raises the same question. In the case of natural areas the challenge further increases because it is hard to know earlier landscape conditions with any precision (there are no blueprints available to consult). Natural-area restoration is more challenging also because nature itself continually evolves. Not all changes taking place in nature are human caused and it can be difficult to know which changes are due to human action and which would have occurred without human presence.
Aside from the question of timing—how far back to go in undoing human changes—there is an even more basic one: Why is restoration a good idea? What is its purpose?
Presumably the point of restoration is to reduce the ill effects of a human misuse of nature. But is the desired end goal a landscape that is being well used by people? Is the work, that is, guided by a distinct vision of use and abuse and by a plan to eliminate abuses while continuing or expanding the legitimate uses? This could be the case, and sometimes is. Quite often, though, restoration means pushing people off the land completely and returning it insofar as possible to conditions that preceded human arrival. The goal, that is, is wilderness-type conditions as of some point in time (for instance, before European settlers arrived in a place). Once again, the line between use and abuse disappears and all human change—or perhaps all change by non–native Indians—becomes abusive. Once again, the charge of misanthropy resonates, even as local communities are benefitted by the revived presence of nearby nature.
Many restoration advocates are likely to dissent from this claim, and with good reason. Some restoration does not aim to undo all human change. It looks backward in time but not all the way to a time before human settlement (or, again, before European-emigrant settlement). Other land restoration work seeks to cover over the ecological scars of misuse without any real thought of reviving the precise biotic community (in terms of species composition) that once existed in the place. Still, restoration as a call to action inevitably conveys a message of moving backward, not forward. It implies that human changes have been bad without any offsetting message that human changes to nature quite often are good. This omission can prove especially confusing and even hurtful for families that have used the land being restored—the farm field, for instance, that is being put back to native grasses. One message embedded in the call to grassland restoration is that the farming of the land was misdirected from the very beginning. It is not a message, needless to say, likely to go over well with families that have farmed in a region for generations and are proud of it, families whose ancestors may have labored to break the sod and drain the fields so that the land could produce food and fiber.
Restoration is clearly a much-needed enterprise today. It should be guided, however, like all environmental work should be guided, by a thoughtful vision of people living well in a place, by some overall understanding of what good land use entails at large spatial scales. If well conceived, that understanding would provide for lands and waters that are off-limits to intensive human use, places that promote components of good land use that do not directly serve the basic needs of people living today. Without such an overall normative vision, however, restoration can too readily also come across as misanthropic to those prone to question it. It can send the unhelpful message that all human change everywhere is bad and needs to be undone. More than that, it can suggest that environmental progress comes about by taking lands from human use and setting them aside, as if people could not live on lands in ways that sustained their ecological health.
The well-known reality that nature itself changes over time, that it is inherently dynamic, poses a special challenge not just for ecological restoration but for making sense of our place in nature generally and endeavoring to produce a vision of good land use. One problem linked to this dynamism is that nature seems to offer a moving rather than static target of healthy functioning and composition. What does it mean to respect nature when nature itself is changing? Much natural change comes about through the efforts of particular life forms, thereby posing a related question: If other species change nature and if their changes are legitimate, part of nature’s dynamism, then how should we think about human-caused change? The challenge here gains depth when change is considered in evolutionary terms and is understood through a cultural lens schooled to interpret competition-driven evolution in progressive terms. If change comes about through competitive pressures that generate progress, how can that change be normatively wrong?
Like all living organisms humans are fully embedded in nature. The air we breathe, the water we drink, the food we eat, the sunlight that is so necessary for metabolism—all come to us from nature and we cannot live without them. Our psychological health is also linked to nature in complex, poorly understood ways. We evolved to live in particular types of places and can feel ill at ease when pressed or lured into alien living conditions. The parts of nature that we directly consume are, in turn, themselves also embedded in nature systems. The flourishing of terrestrial life forms begins with plants growing in soil and sunlight. The soil itself must be fertile, and its fertility depends upon complex cycles and flows of nutrients. Water is part of the productive equation and it must be available at the right times and quantities. Too much can halt growth, erode the soil’s fertility, and bring to the land surface salts that diminish production. The interconnections and interdependencies are countless, quite often taking the form of symbiotic relationships in which particular organisms can endure only if other organisms also endure.
One force driving nature’s dynamism is the complex set of mechanisms commonly termed “evolution.” Individual species and mixes of species evolve in competitive settings, new species arising by gradual means and old ones declining and disappearing. Over time, evolution has led to the emergence of living creatures of extraordinary complexity. It pushes also toward natural communities that become more biologically complex over time as the number of different species rises and as the species collectively become more specialized and efficient in using the geophysical resources of a place. Collectively they do better at taking advantage of sunlight, engaging in primary production, and keeping nutrients in the local system as long as possible. These observable patterns, however, always have exceptions—systems in which fewer species dominate and localized species variety decreases; systems in which soil erodes rather than, as usual, slowly builds; systems in which primary productivity seems to decline rather than rise. Natural communities and thus their constituent elements are affected regularly by various disturbances, due to fire, flood, extreme weather, gradual climate change, and the like. All of them are forces of change. Vigorous biotic systems often recover from disturbances but never return to precisely where they were before the disturbance took place.
When Charles Darwin’s writing on evolution first appeared, it came to a reading audience, particularly in Britain, that already believed in progress and already had faith in competition as a means of promoting growth. It believed also that large historical forces were at work in the world, biological and social forces akin to the physical laws that guided motion. It was easy for a readership like this to interpret Darwin’s evolutionary theory of natural selection as just such a force bringing about progress. The stronger, faster, more physically able organisms were the ones who survived and reproduced. Their greater physical abilities, the mere fact of their competitive survival, meant that they were better than the genetic variations that lagged behind. Darwin, as already noted, did not frame his evolutionary theory as a story of progress; it was simply a tale of long-term physical change, he stated, aptly summed up in the neutral phrase “descent with modifications.” It was Darwin’s popularizers who gave evolution its overtly progressive caste and broadened its application into social and cultural spheres. Chief among them in Britain was Darwin’s intellectual champion, T. H. Huxley, who had earlier come up with the phrase “survival of the fittest.”
In educated minds of his day Darwin’s writings on biological change were patched together with the many writings by other scientists on geologic shifts over time: on the creation of mountains and canyons, on changes in river courses, and on the various physical forces that, in dimly understood ways, somehow shaped physical landscapes over the eons. The physical earth was also evolving it seemed, perhaps also progressing, along with its many life forms. Further evidence of natural change soon came out of the new science of ecology, a science that studied organisms within their communities and biotic communities as such. Natural communities studied as wholes, it seemed, were also dynamic, most evidently when a community responded to a major disturbance by slowly returning to something close to its earlier biological condition. Change, in short, seemed to be part of the way the world worked. Other species, it was quite clear, altered the worlds in which they lived by ways of processes that at least carried suggestions of being progressive. Humans did just the same; they too were agents of natural change. By Darwin’s day, few people outside religious settings believed that the earth had been specially created for humans. But few also seemed to doubt that it was entirely proper for humans to participate as agents in these ongoing processes of changing nature as they went about draining marshes, cutting forests, and redirecting rivers. Change was entirely natural and could be, it often was, good.
These various natural realities and cultural interpretations, all having to do with change in nature, have combined to make it more difficult for people to identify how they might best fit in the natural order over the long term. If nature were static and perfect, then the challenge would be to live on it and in it without materially disrupting its basic structures and modes of operation. But nature is dynamic. Its condition at any given time and place is contingent. As for the once-popular idea that nature is perfect, the notion makes sense only within a religious worldview that sees nature as God’s handiwork and that attributes nature’s perfection to God’s own perfection. When that standard of evaluation is set aside, then nature simply exists and it operates dynamically in some ways rather than others. Nature is simply a matter of “is” rather than “ought.” There is no right or wrong inherent in any natural conditions, no better or worse, except insofar as people evaluate it in those terms taking into account (as they likely would) their needs and otherwise using standards of their own choosing. As for nature’s built-in dynamism, the changes it brings about are also neither good nor bad on their own. It is up to people to make sense of the changes, to view them through a normative lens.
In sum, we find ourselves needing to draw a line between the use of nature and the abuse of it and to do so in a natural world that changes on its own and that necessarily changes whenever we, or other species, live in it. Nature provides no static vision of ecological health for us to use as a guide. For that reason and for others, we cannot simply turn to any particular natural condition and say that the “is” of nature’s existence provides a normative “ought” to use in judging how we interact with nature. (We return to the issue in the next chapter.) Nor can we sensibly use any sort of wilderness baseline as our measure of good land use, not for landscapes where we live and get our food. With God the creator largely put to the side—and, in any event, having abandoned any notion that God’s perfection translates into nature’s perfection—we are left to our own devices when it comes to distinguishing the good in nature from the bad. To be sure, nature works in some ways and not others, and we have abundant reasons to adapt our ways of living based on nature’s functioning. Still, nature has hardly made our intellectual and moral work easy. It has simply not given us clear guidance on how we might successfully change it.
Our best factual knowledge about natural systems comes to us from scientists. In the case of the biological functioning of natural systems it comes from the loose category of researchers known as ecologists. Ecology is one of the less solid sciences in that, in its study of the outdoors and its effort to make sense of it, the science necessarily deals with systems that it cannot fully control. Some ecology work is done in laboratories or by computer simulation. But most of it involves heading into the outdoors and gathering data from it. The data that await collection are essentially infinite—sobering reality number 1—and nature’s parts and processes are all intricately interwoven—number 2. Inevitably, then, ecological study requires a scientist to formulate criteria for deciding what data will be collected from this infinite pool. Ecologists are good at this work, not just at developing data-collection criteria but also at formulating and undertaking experiments in nature to test hypotheses. Still, experiments conducted outdoors are never fully controlled, not like in chemistry laboratories. Conditions in different outdoor places are never the same, or the same in a single place at different times. The many factors that influence natural conditions challenge comprehension. Beyond that and beyond the already-mentioned limits on human cognition, there is the reality of human choice that goes into selecting the data and the necessarily tiny sample size that typically results. When studying a complex natural system, what features seem most important, and how can the countless features be brought together to describe the natural whole? A sense of importance is needed, which necessarily brings in values and culture.
A story told in recent decades about the history of ecology as a scientific discipline prominently features a claim that ecology underwent a paradigm shift sometime around or after the middle of the twentieth century. (Different versions of the story give different dates.) At some point, ecology as it summed up natural systems shifted from emphasizing the order and functioning of a natural system, presenting it as having rather stable, predictable elements, to a focus instead on a system’s inherent dynamism and unpredictability. The old view tended to stress the ways in which natural systems endured over time. The new view tended to stress the ways in which it changed through random factors and from competition.
Such a shift certainly did take place, though it is a matter of opinion (and perhaps little consequence) whether it was material enough to qualify as a paradigm shift. As scientific knowledge has risen, there is greater awareness of the dynamic elements of systems, and greater recognition that systems, once disturbed, do not simply return to their earlier conditions. Community responses to disturbances are affected by more seemingly random factors so that a system, once recovered from perturbation, might differ considerably from its predisturbance state.
This new emphasis on community-level change, particularly when presented as the product of chance and competition, conveys a sense that nature really isn’t a delicate, fine-tuned system that is easily degraded. Particularly if much of what we see in nature is the product of random factors—storms, the movements of seed carriers, particular rain patterns—then different random factors could have produced rather different systems, which we would view as equally natural. Maybe natural systems are tougher than we thought; maybe human-induced changes don’t differ in kind from changes brought by other sources of disturbance and random processes. This message seemed implicit in the new ecology of disturbance, and it was a message that, predictably enough, was greeted warmly by industrial-interest groups when they got wind of it. The natural systems that people were disrupting were not just themselves dynamic, not just themselves products of actions and competition among life forms. They were the results of physical and random factors that could easily have given rise to something much different.
It is certainly true that this shift in ecology, however major it was, adds further intellectual complication to the line-drawing task while also suggesting that humans have greater freedom to manipulate nature than often claimed. Like all pertinent natural science, these new findings need to be given weight. As we do this, though, it is useful to keep in mind the points just made about the scientific field, both the exceptional challenges that ecologists face in making sense of nature and the roles of values and other social influences in shaping how ecologists go about their work. In significant ways, the overall shift that took place in the ways ecologists were talking about natural systems—the shift to emphasize change rather than enduring order—was rather directly linked to changes in the ways ecologists themselves chose to frame their inquiries and also in the motives that were driving their researches.
During much of the first half of the twentieth century ecologists talking about nature tended to consider nature’s functioning over relatively short time periods, over decades or at most centuries (for instance, when describing vegetative succession). Their time horizon was relatively close. By late in the century, their successors were prone to talk more often about vastly longer periods—thousands or even millions of years. The longer time frames, of course, allowed for more change to unfold and their descriptions highlighted that more significant change. Earlier scientists often talked about systems apart from the natural forces that from time to time disturbed them. Their successors, in contrast, commonly found it more useful and accurate to include disturbance regimes as part of the system being studied, not external to it. This shift in focus, too, gave nature’s dynamism a greater place in the descriptions they produced. Further, many scientists in the earlier period were interested in studying flows of nutrients and other components through natural systems, a type of work that paid less attention to the shifting species composition of a system over time. Later scientists, in contrast, often wanted to study these shifts in species composition and populations directly, which meant studying the components of a system that were often most likely to respond to random and competitive factors.
As a final point of difference, leading ecologists in the early to mid-twentieth century—Victor Shelford prominently among them—were often involved personally in the work of saving high-quality natural areas from degradation. As part of that work they needed to develop ways and terms to categorize natural areas by type so that samples of each could be protected for future study. (Shelford’s Natural Areas Committee of the Ecological Society of America, an active agent for preservation, would evolve in time to become the US Nature Conservancy.) Necessarily this motive forced them to look at the community level and to describe it in a given point of time (typically the present), to come up with labels for types of communities, and to depict them in ways that seemed more enduring. Later ecologists, in contrast, left such work to conservation advocates. As they did so, they lost one of the main professional reasons for categorizing community types and labeling them.
Nature’s communities, of course, did not literally come in discrete types; nor did they have anything like clear boundaries. Shelford and his colleagues knew that reality perfectly well, just as they knew that nature was dynamic, that systems once disturbed did not always return to original conditions, and that patterns of succession did not always lead to stable conditions. Yet their conservation work required them to talk about communities as distinct things, to situate them in time, and to give them a type of entity status. They also used this typology as a means to introduce students to wide varieties of ecological communities in a type of education (learning thousands of species) that would disappear in the educational push for early student specialization. Looking on and then back, their ecological successors viewed much of this categorization and labeling work as artificial if not simply wrong scientifically in that it didn’t correspond well with reality. Without the need to categorize lands for conservation, without any plan to take students (as Shelford did) on long summer trips to study wide varieties of natural areas, later scientists viewed this early work as unhelpful if not misguided even as it lived on in the work of state agencies charged with taking inventories of natural areas and identifying the best for protection.
These various differences over time in ecologists and their questions and motives surely offer a partial explanation for why late-century ecologists tended to stress change in nature more so than did earlier ones. Historian Donald Worster has added another interpretive component to the story by observing that scientists themselves, including ecologists, are never able to remove from their work their own values and understandings of the world (a commonplace view in the sociology of science). It was not coincidental, Worster concluded in his study, that ecologists late in the twentieth century tended to stress nature’s dynamism right at the time when prevailing political and social thought in the Western World (the United States and Britain in particular) took a turn toward more individualistic, libertarian values, with a rising distrust of government and a tendency to see the world as a collection of competitive parts, not social wholes. Conservative values favored the free market—a dynamic, atomistic system—rather than the government with its top-down, centralized regulation. This view of the social and political realms, as chiefly individualistic and dynamic, rose largely in tandem with the ecological view that nature itself was in fact pretty much the same. Nature, too, was a chaotic system of individual competitive parts characterized by ceaseless change, just like the social order and the free market.
Whether or not Worster is right in his suggestion that culture and politics bled into ecology it remains true that ecologists struggle and will continue to struggle trying to make sense of complex natural systems. They will look at systems over time from different angles, asking different questions, using different time frames, and coming back with varied pictures depending upon the parts of the systems given interpretive primacy.
At the same time, however, the basic interconnections and interdependencies of nature are now quite firmly understood, including the processes that generate fertility and productivity. The basic ecological processes, including those responsible for primary productivity, are reasonably well described. So too is the fact that species come and go over time with new species very slowly displacing old ones and, to varying degrees, taking over their functional roles. In important ways natural systems do display distinct persistence over time—particularly in time frames relevant to human planning—and much change that does naturally occur is at far slower paces than the kinds of changes people make. Natural change that takes thousands or millions of years to unfold is, for human planning purposes, irrelevant.
These struggles by ecologists to make sense of the world further complicate our collective effort to know how to live. Still, ecological studies provide us the best knowledge we have and can get. We would be foolish not to make use of them even as we should not be surprised that new research both expands and modifies our understandings.
One particular danger arises out of this scientific knowledge and scientific uncertainty, and it is usefully kept in mind as we go forward. The danger is that we might look at nature’s dynamism, particularly at the huge changes that unfold over thousands and millions of years, and view them as a green light to make big changes to nature of our own. Given that nature’s systems are dynamic if indeed not transient and chaotic, then why can’t we change nature as we see fit? Such long-term change appears to make ecological restoration seem unscientific in that restoration resists nature’s own inherent dynamism. Dynamism can similarly make the preservation of natural areas also seem unscientific, in that even wilderness areas will evolve over time, gradually turning into something different. The intellectual risk here is hardly hypothetical. It is no surprise that, as noted, industry groups and neoliberal opponents of environmental limits have been quite quick to latch on to ecological writing that stresses change over stability.
Nature’s dynamism needs to play a role in our normative thinking. That said, though, there are significant differences between the typical forms of human-caused change and those that take place due to nonhuman forces. Many of the differences have to do with matters of scale: natural change often occurs much more slowly and, in human time frames, is more localized. There is, of course, the occasional volcanic eruption that instantly alters hundreds of square miles of land. But changes of this type—again in human time frames—take place only on a tiny portion of the earth’s surface, hardly appreciable when compared with the human footprint. In addition, nature’s changes are caused by natural processes that have been in operation for eons, processes that various life forms have learned not just to deal with but often to turn to their advantage. Some human changes (plowing fields and exposing soil to annual weeds) are of this type while other changes (nuclear and toxic contamination, for instance) are not.
Perhaps the most important point to emphasize is this: Nature’s dynamism is simply part of the “is” of nature. As such it has no more normative content than does any other trait or component of nature. The fact that nature acts in a certain way—that it changes over time—does not mean that the change is normatively good (or bad) from a human perspective. Nature’s dynamism is hardly irrelevant; indeed it needs an important role in our standard for judging whether or not we are using nature legitimately. But natural dynamism does not provide an intellectual shortcut. It doesn’t give cause for us to skip the hard work of thinking clearly about how we ought to live on land. Perhaps it gives us greater options to make changes without degrading nature. Perhaps instead it imposes greater limits on how we act if we want to maintain high natural productivity and to enjoy biological diverse surroundings. In any event, we still face the challenge of distinguishing use from abuse, the challenge of identifying the many relevant factors, of giving deep thought to our needs and aspirations, and of somehow bringing them all together into a vision of right living.