Johns Hopkins Magazine - September 1994 Issue


"Environmental refugees," etc.

Feeding the world: Technology has no answer

What humanity is up against, in the view of plant geneticist Nina Fedoroff, is "the limits of the earth to absorb more human population, more human economic activity, more people." The world's population, currently some 5.6 billion people, now grows by roughly 93 million persons a year--about the population of Mexico. That's faster than supplies of food can be increased, says Fedoroff. While world food production continues to rise, the amount of food per person has been dropping for more than a decade. Per capita supplies of fresh water are one-third lower than in 1970.

At the same time, the earth becomes less fertile, partly from overuse and the farming of marginal lands, and partly from the techniques of modern farming. These techniques are only a short-term solution, says Fedoroff: When chemical fertilizers are first used, the farmer gains a phenomenal nine tons of grain per acre for every ton applied to the land. But the miracle passes. In the long-term, irrigation causes toxic salts to accumulate in the soil, which then grows nothing. Bugs evolve resistance to pesticides. And as for chemical fertilizers, says Fedoroff, yes, you can use them to compensate for topsoil loss--for a while. After a time, though, larger and larger amounts of fertilizer are required to get the same yield. Finally, a point is reached-- where much of the developed world is now--that adding more fertilizer gains little.

Fedoroff, a researcher at the Carnegie Institution of Washington's Department of Embryology on the Homewood campus, says that new dwarf species and new strains of plants that respond especially well to chemical fertilizers (i.e., the "green revolution") are scarce these days; she believes those approaches have just about reached their limit.

Fish and other food from the waters of the world are also declining, as a result of overfishing, siltation, and various forms of chemical pollution-- especially from pesticides and fertilizers. "Agriculture is the most environmentally damaging thing man ever invented," says Fedoroff.

Meanwhile, the world's population keeps on growing; that is the root of the problem, and one for which there can be no technological fix, Fedoroff says. The world population has more than doubled from 2.5 billion in 1950. At current fertility rates, it will double again by 2035. "Technology and science can't pull humanity out of a disaster caused by too many people," says Fedoroff--a concept that, for the first time, she now sees publicly acknowledged.

In 1992, the Royal Society of London and the National Academy of Sciences of the United States--probably the two most prominent scientific societies in the world--issued a first-ever joint statement on population growth, resource consumption, and development. The statement says that the world's population growth must be stemmed, as well as the industrialized world's wasteful and polluting use of resources. Otherwise, Fedoroff summarizes, "science and technology can do little to prevent increasing misery, increasing floods, and increasing economic and climatic disasters, all of which are interconnected." Later, in October 1993, the first-ever Science Summit on World Population, sponsored by the world's scientific academies, concurred.

Population pressure is most acute in the less developed nations, and as that pressure increases we all know that more and more firewood is cut, more and more cattle are grazed, more and more land is overcropped and deforested. The scenario is familiar. Massive erosion results, and people must go further and further, abusing more land, in their desperate search for food and firewood. In the mountains, such as the Himalayas, deforested soil cannot absorb the rain, causing floods in the plains below (most famously in Bangladesh).

What's new: In addition to the immediate human suffering, says Fedoroff, it is now known that these effects cause climate change, a fact that scientists have only recently realized because it just wasn't obvious. For instance, South America's traditional slash-and-burn agriculture worked very well when a single farmer cut down a small area, used it, and moved on--the forest could return, and certainly there was no significant climatic effect from a five-year farm-sized gap. Now that millions of acres are being transformed into grassland, however, Fedoroff says it suddenly becomes clear that the plentiful moisture of a tropical rainforest is "largely caused by the biological activity of the trees." In Malaysia, the remaining forest is no longer too wet to burn, and for the first time, Malaysia gets forest fires. It is not yet clear what a drier tropical zone will mean to global climate--perhaps much.

A social consequence of these global changes can be seen already: growing numbers, currently more than 20 million, of "environmental refugees"--people whose land is so blighted that in order to survive, they must leave. Africans, for instance, are driven from home not only by war, but by war combined with famine, notes Fedoroff. She sees the current African wars as fights over scarce resources--resources that would have been adequate for the population of 20 years ago.

No part of the globe will be exempt, including the peoples of the United States and Western Europe, says Fedoroff. Having achieved industrialization and low birth rates, she says, "we think we're immune. We do not understand why suddenly we have problems with so many people flowing into our countries. And this is not a problem that is going to go away. It is estimated that 90 percent of the population growth of the next century, even the next decade, will occur in the less developed countries of the tropics, which are already bulging at the seams." Both Florida and California--highly prosperous states until a few years ago-- are suffering in part from the strain of absorbing refugees. Fedoroff says, "People will come north. They're coming already."

So is it too late? Fedoroff pauses. "I think it may be. But I also think that every one of us has the responsibility to act as if it isn't, and to do whatever he or she can to contribute to solutions."

As her contribution, Fedoroff will leave Carnegie in June 1995 to become professor and director of a biotech center at Penn State. There, working through both traditional agricultural researchers (like plant breeders) and scientists of the most modern and genetic stripe, she hopes to help stave off a worldwide food crisis with recombinant DNA technology. For example, in one current approach, genes for bacterial molecules that poison insects can be transferred into plants. In one such--Dipel, now on sale in hardware stores--the farmer never needs to spray, because any insects that actually chomp on the crop will die.

The recombinant approach is controversial, because people are afraid of it. "There are barriers," Fedoroff says. Nevertheless, she's on the charge. "Society has given me a very long time to sit in my corner and do my research. I feel that it's time to pay some of that back--knowing full well that I could fall on my face and accomplish nothing." --EH

On avoiding extinction

Steven Stanley is an authority on fossil bivalves and punctuated evolution. So it comes as no surprise that when he looks at the present, he sees it through the window of the very distant past. And the message he brings back is mildly hopeful.

At least in temperate parts of the world, says Stanley, the groups of plant species we think of as "belonging" together may not be so invariable. Therefore, we need not expect catastrophe just because our ecologies are not the way they were a hundred or a thousand years ago. The key word is "variety."

"In thinking about the future and the way we relate to natural ecosystems," Stanley's thinking has been altered by "the discovery that our biomes, what we view as being natural biomes--associations of plants, especially trees--are not really ancient. In temperate zones like the ones in North America, they do not represent ancient co-adapted assemblages of plants that evolved together to fit together effectively in nature. In fact," says the professor of earth and planetary sciences, "they are temporary associations that formed while we emerged from the recent ice age, just 10 to 15 thousand years ago."

Stanley knows that from fossil pollens, which clearly show that 20,000 years ago, oaks and pines grew together down in what is now Georgia and Alabama, as part of a totally different arrangement of species. Today, their only association is in the pine barrens. Inland, oaks are centered in the Appalachians--they like a warm climate--whereas pines are mainly found in the north. Furthermore, Stanley sees similar shifts in fossil sea life. "So it's clear that as climates change, biomes do not shift as units. Rather, individual species shift in accordance with their environmental requirements."

The implications? "Certainly we want to preserve species, as well as important and beautiful associations of species. But we can't necessarily say that the assemblage has to be exactly what we found here." More doably, says Stanley, foresters and agronomists can aim at "associations that work compatibly, that are beautiful, and that preserve a lot of diversity."

What we must not do, in Stanley's view: "plant monocultures, like a lot of the lumber companies have done. Monocultures are unhealthy. It's like people living in cities. When they're crowded together, they give each other diseases. It's the same with trees." If the trees are all one species, a single blight can wipe out the whole forest. "If you look at Cro-Magnon man 20 or 30 thousand years ago, they were big people. They were like Europeans today, but the men were 6 feet tall. That's because they didn't have a lot of the childhood diseases that we have now, and they ate well--meat and berries and various kinds of natural food. When people moved to cities, they got smaller, and they suffered enormous consequences in terms of disease. The same is true of plants in nature."

Stanley agrees that the globe is probably entering another period of mass species extinction, largely from human actions, including the ones that are probably warming the globe. "If you're going to kill off species all over the world, a change of climate is the best way to do it."

Any lessons from the past? Yes: In species extinction, expect the most loss in the tropics. Tropical forests do not create deep loam like northern ones; the soil can therefore turn into desert with extraordinary ease. And tropical biomes, again unlike the northern ones, have not suffered from unstable climates. Thus they do have long-evolved and extremely specialized interactions, such that the loss of one species can do in several others. For instance, a fruit tree that can be pollinated only by a single bat species will go extinct if the bat goes. "There's a tremendous domino effect," says Stanley. In mammals, expect the greatest loss among large ones. Needing more food, they are more scarce to begin with.

Although humans are big animals, Stanley does not believe we are an endangered species. "We have to recognize that we have an extraordinarily broad ecological niche. We've been omnivores long before civilization arose. And because of our intelligence, we can find ways to adapt to all sorts of conditions," he says.

"We can get to all corners of the Earth--all elevations, all climates. We are relatively resistant to any single agent of extinction, because it would tend to focus in one region, or to people who behave in a particular way. And we are unique in that we are constantly expanding our ecological niche. We can live in outer space if we want, some time in the future. We have people living for many days beneath the ocean. So we can't compare ourselves to large animals in being especially vulnerable." - -EH

Grassroots environmentalism

When Ellen Silbergeld attended the first United Nations environmental conference in 1980, she saw "heads of state, scientists, and mostly men and white faces from affluent countries." Twelve years later, at the U.N. conference held in Rio, she saw all sorts of faces--black, brown, white, female, and people from all walks of life. The change in faces, she says, represents an overall shift in the environmental movement.

"Over the past 10 years, and accelerating very much over the past few years, there has been a transformation of environmental issues from the interests of a small elite to the concerns of people who are in many ways marginalized and excluded and oppressed," says Silbergeld (PhD '72), professor of toxicology and epidemiology at the University of Maryland, and an adjunct professor of environmental health sciences at Hopkins's School of Public Health.

Poor communities and communities of color are often the ones that bear the environmental burden of development, says Silbergeld. They are starting to speak out about problems in their own backyards, which is forcing members of the "elite" to broaden their views. "Now we're not just concerned about burning down the rainforest, says Silbergeld, but also about "people in the rainforest."

In almost any region of any country, says Silbergeld, the grassroots environmental movement is taking hold. A few years ago, she visited the family of her foster child in rural Thailand. Did the family want to hear about Michael Jackson, Alien movies, or other popular culture we export? No. More than any other topic, they wanted to talk about deforestation, pesticides, and the dumping of waste into the river. "I could have closed my eyes and been talking to a group of Americans," says Silbergeld.

The movement has grown so quickly, says Silbergeld, in part because "environmental problems have become so gross that they cannot be ignored by anybody." Environmental groups, particularly Greenpeace, have also increased interest by publicizing the problems--though with increased publicity, some environmental issues have been distorted, adds Silbergeld. "Is .001 percent of pesticide in kiwi fruit in 1 percent of the world's population the big risk, or is it lead in most of the developed world?" she asks. "While we are fixated on relatively small risks, there are other huge environmental problems out there." --MH

Facing up to making choices

As Laurie Zabin looks at the globe, the population dynamics researcher sees three imperatives converging, like massive armies marching toward a single battlefield, recruiting soldiers as they go:

As these three forces intersect, says the School of Public Health researcher, something has to give. Choices must be made, which most people are not yet willing to do. Take the current debate in the United States over health care. "Conservatives say, So what, everyone can't have it. Liberals say, But everyone must." Others try to redefine "it" into something manageable--but even if that succeeds, swelling population and technology will soon recreate too much demand for countless possibilities. Once the fruits of the Human Genome Project are in hand, for instance, the same issues arise: Given all these people, who will get genetic testing and treatment, for what purposes, at what level, and how on earth can we pay?

"Dynamic systems always involve choice," says Zabin. "Whether it's natural selection or whatever, something lives and something dies. We are blinding ourselves to the knowledge that technology and knowledge both force choice. Either we will make choices, or choices will be made for us--and we may not like the consequences."

Zabin's specialty is population dynamics, more specifically adolescent pregnancy, which she sees as one such consequence. "We tend to blame the teenagers, and the problem is not the teenagers! The problem is that technological change put millions of people out of work, and family structures that were dependent on the parents having jobs broke down."

In passing, Zabin wonders why no one talks about the issues of control that are posed by today's technologies. What if the new genetics, for instance, were to be controlled by just a few people? Or world communications? "These are huge moral issues. The kind of control a tyrant could exert 500 years ago is nothing compared to what a tyrant could exert today. Every single cave in the world would be endangered. It's a frightful risk."

Can humans possess knowledge and not use it? Could we understand the human genome, yet give genetic testing to no one? That's not an option, says Zabin. "Knowledge is one of the choices we have made. We have a basic principle that if we can know something, we should go ahead and study it." -- EH

Catch if catch can

"Any resource that is openly available will be used up entirely." That is the gist of the "open resources model," generally accepted among economists. Philip Curtin, Hopkins historian, Africanist, and MacArthur fellow, thinks it applies to all the world's resources.

To understand the model, take the example of a fishing village and its fishery. "The proposition here," says Curtin, "is that if you have a limited number of fish out there, from the point of view of each individual fisherman, your best option is to catch as many as you can. Because if you don't, someone else will. And the fish will disappear. But they will disappear even if you don't catch 'em."

In such a situation, there is no incentive for restraint, but every incentive to take while the taking's good. That is true even for a person who knows and regrets the damage done, he emphasizes. "So the interest of each individual fisherman is to destroy the environment that has sustained the fishing community over all these years."

Curtin's other example comes from the fur craze of the 19th century, when both beaver and buffalo were essentially eradicated in the United States. The sea otter was fished out in both the U.S. and Canada. "In general, people's self-interest will lead them to go on and basically destroy a resource for their own purposes," Curtin says. "That's natural. People are often selfish."

To preserve any resource, then, there must be an intervention. There must be some higher authority that takes a long-range view and has the power to enforce it--as there was in the case of sea otters. The only reason we have otter now, says Curtin, is that the "Russian equivalent of the Hudson Bay Company had a monopoly, so in its own interest it protected the sea otter." Eventually, the animals spread back from Alaska into other parts of their former range.

More usually, the authority has been a government. Curtin says the open resources model is extendable to the situation in the former Yugoslavia. "Until you had a state big enough to protect minorities from each other, in an area where everyone is a minority, you had constant warfare." Then after the collapse of the big state, the warfare resumed. "The same is true in Rwanda, Liberia, Zaire, and Angola_. Something like the Austro-Hungarian Empire gets to look pretty good."

In today's world, governmental clout seems to be waning (see pages 54-56). For instance, it is hard to see what authority will protect public U.S. land from improvident mining, grazing, and logging. The Department of the Interior is helpless, Curtin believes. "The president's need of those western senators is such that he can't let Bruce Babbitt loose," and the senators need the PACs. --EH

Out of our hands?

Alan Walker discourages a human-centered, static view of the world as being "incredibly short-sighted." What humans do to the globe, he thinks, may be less important than what the globe does to itself. "You have to realize that my own home country [England] was nothing but a sea of mud and rock after the glaciers withdrew. There was no life under the ice sheet, and it must be the same with geomorphology all over the world." Yet, a mere 20,000 years later, those former mudflats have metamorphosed into a complex tapestry of cities, farmland, forest, and so on.

On the scale of 50 years, he points out, we can see islands disappearing in the Chesapeake Bay. On the scale of a day, we might see a volcanic explosion that, like Krakatoa in 1883, would fill the skies with ash and create a worldwide "summer that never came." So, says the anatomist/paleontologist, a MacArthur-winner who has worked in Africa with Richard Leakey, "earth is a very dynamic, unpredictable place. Humans just aren't used to seeing it that way."

He does wonder about human extinction, especially as resulting from population pressure. "The world is populated by two sorts of organisms," he says, matter-of-factly. "Bacteria and algae, and the rest of us. We could be looked on as fermentation chambers for bacteria. And bacteria and algae will survive even a nuclear holocaust."

On balance, however, Walker refuses to be a doomster. There is a feeling of doom in the air, he says. Everyone worries. But Walker wonders, contrariwise, "how much this feeling is due to our having so much information." A hundred fifty years ago, a letter took three months to come from the Caribbean. "Today, everyone has transistor radios. Everyone knows what goes on everywhere, so you can get terribly worried about something happening in China."

Walker is unsure such worry is justified. "When I go to Africa for months on end, I don't hear these things. When I come out and read the news, it's all the same stories, but the characters have changed. Instead of Gennifer it's some other woman. Instead of Somalia it's Rwanda. I think it's very easy to worry about everything. People are expected to worry compassionately about all these things. I suspect that most of us don't have enough compassion to go around." --EH

Written by Elise Hancock and Melissa Hendricks.

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