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Headline News, Science Views (1991)

Chapter: 6 Scientific Horizons

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Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
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6
SCIENTIFIC HORIZONS

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×
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Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Knowing About Trees

John C. Gordon

Some years ago, a New Yorker cartoon showed a well-to-do man and a child walking in the woods. The caption read, "It's good to know about trees; just remember that no one ever made big money knowing about trees."

Times have changed; forests are now important not only economically, but environmentally and politically as well. Nearly every day we hear about global warming, deforestation in tropical areas or a dispute over ancient forests.

What is surprising and disturbing is how little we really know about trees and forests. A report released yesterday by the National Research Council says research on this vital resource is surprisingly weak and fragmented. Our efforts to understand forests are inadequate to sustain the benefits they provide, let alone to meet the needs of a more populous and competitive future.

For example, forests are widely regarded as a safeguard against environmental threats, most recently global warming. That is because trees remove carbon dioxide, a greenhouse gas, from the air through photosynthesis. Globally, trees remove massive amounts of carbon dioxide from the atmosphere. They also shade and cool their local environment by evaporating water from their leaves.

Political leaders and scientists probably are correct to hail forests as environmental buffers and partial antidotes to global

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Drawing by Patrick Burke

The Bridgeport Post, Ct.

warming. Yet the knowledge base in which their claims are rooted is frighteningly shallow. Foresters cannot predict quantitatively the effects of forest loss—or gain—on climate. They could not respond with much precision if a political leader asked how much, say, a billion new trees would relieve global warming. Their uncertainty might cause the leader to think twice about acting at all.

Similarly, little is known about the biology of thousands of forest species, particularly "minor" components like shrubs,

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

insects and microbes. This is especially true of tropical forests in the Amazon, Africa and elsewhere, where biological diversity is threatened. Those fighting to preserve these precious areas are hampered by not knowing what they contain.

The same problem applies closer to home. It is shocking how little we know about the biology and biotechnology of the several hundred species of North American trees upon which we depend. Nor do we know much about forests in a system sense. The oldest forest ecosystem studies are about 25 years old—and there are only a few of them.

This lack of knowledge hinders not only environmentalists but those who depend on forests for their livelihood. The worldwide demand for paper, lumber and other forest products has been growing steadily, but timber companies need improved methods to overcome insect, disease and pollution threats. In urban forests, meanwhile, only one in eight trees is being replaced; new techniques could help preserve these groves that so enrich city life.

Across-the-board improvements in forestry research are essential for all these purposes. Our efforts to understand forests must become broader and deeper, making use of the latest scientific techniques. Recombinant DNA technology, for instance, could help reveal the genetic structure and change in forest organisms. This could lead to new commercial trees that resist insects and disease more effectively. Increased understanding of the interaction of plants, animals, microbes and people in forests would enable foresters to manage these complex ecosystems more effectively.

At the precise time that we expect more from forests, however, we actually are reducing our efforts to learn about them. Since 1978, the number of undergraduate degrees awarded in forestry and related fields has declined by half. The research budget of the U.S. Forest Service has dropped in buying power even as forestry research conducted by industry has decreased. Many research facilities are outmoded.

This is surely foolish, and sweeping changes are needed to remedy the situation. More competitive research grants, a national forestry research council to provide leadership, and centers of research focused on major areas of concern are all ingredients of a revitalized forest future.

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Romantic visions of the forest primeval are fine for story books but inadequate for the environmental and economic challenges we face. Without our urban and rural forests, our cities will be hotter, our countryside windier and drier, and our supply of wild birds and animals smaller and less diverse. We need our forests and must learn more about them if we are to keep and use them.

October 11, 1988

John C. Gordon, dean and professor of the School of Forestry and Environmental Studies at Yale University, chaired the National Research Council committee that examined forestry research.

* * *

Together to Mars—But with Deliberation

Eugene H. Levy

The United States and the Soviet Union are both planning missions to Mars, and a joint project has been suggested as a way to share costs and promote goodwill between the two superpowers.

Even before the recent summit conference, Soviet President Gorbachev suggested the possibility of cooperative Mars exploration. President Bush has committed the United States to manned exploration of Mars, but some question where the money will come from.

Increased cooperation with the Soviets sounds attractive. But is it realistic? How should it be done? And, considering the complexity of a Mars mission and the differences between the two countries' political systems, technologies, languages and the like, how far does it make sense to go at this time?

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

I chaired a National Research Council committee that was asked by the National Aeronautics and Space Administration (NASA) to define the best approaches to international cooperation in Mars exploration. We concluded that cooperation with the Soviets—along with European countries, Japan, and Canada, among others—could produce many benefits. We recommended a U.S.-Soviet cooperative program of unmanned robotic missions to visit Mars, make measurements, collect samples and, leaving instruments behind, return to Earth.

However, we also found that close technical cooperation with the Soviets would be likely to create problems at this stage of the relationship. For now, we recommended against the two nations dividing responsibilities for actual joint missions.

Mars exploration could serve many human interests, spanning national boundaries. The surface of Mars reveals a history of startling change. Cold, dry and nearly airless today, Mars apparently once had abundant flowing water, suggesting higher temperatures and a thicker atmosphere than now. The planetary changes recorded in Mars' surface may represent a spontaneous transition from a potentially life-supporting environment to a lifeless one.

We do not yet understand what causes such great change in a planet's environment. One motivation for studying Mars is to find out. Learning why Mars changed will teach us about planets in general, something essential for understanding Earth. We will not be able to understand and predict Earth's behavior confidently until our theories also explain what happened to Mars.

For these and other reasons, Mars exploration is a natural candidate for ambitious international cooperation. In such an effort, the United States and the Soviet Union would occupy unique positions. Only they have the experience, the current technical capability and the expressed vision to undertake or lead an intensive Mars exploration. For some time, the overall approach to Mars exploration will depend on commitments made by the two superpowers.

However, the United States and the Soviet Union have little experience with technical cooperation. Communication

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Our best evidence, from the 1976 Viking mission, indicates that there is now no life on Mars. But wetter and warmer conditions in the past may have enabled life to begin and evolve. Scientists speculate that biochemical or structural fossils might have been left by early martian life.

The space age gave human beings the vision of Earth as a planet and impressed upon us the isolated and fragile nature of Earth's environment. Our planetary perspective was further sharpened after investigations of Mars revealed that planets can undergo extraordinary environmental change, perhaps even from a life-supporting world to a lifeless one. That prospect was not seriously considered before explorations of Mars. Studying our planetary neighbor provides an irreplaceable perspective on planetary environmental change.

—E. H. L.

is poor; neither side fully understands the institutions, practices or capabilities of the other. Close cooperation would raise concerns—some reasonable, others unreasonable—about technology transfer. Moreover, space exploration projects involve long-term commitments. Joint missions, in which each nation is greatly dependent on the other, could become hostage to unexpected political events.

Given these problems, it makes sense for the two countries to develop cooperation gradually, although steadily, beginning with robotic missions that use artificial intelligence to explore Mars and return samples to Earth. Automated exploration would be extremely beneficial in itself because of its scientific value, social inspiration, potential to spur technology and relative economy. Decisions about human exploration could be made later.

Both nations would benefit technologically from robotic exploration of Mars. Important advances could be expected in rocketry, robotic manipulation, machine intelligence and other fields. It is not clear that either nation would want to relinquish to the other the development of the major enabling technologies.

An initial phase of Mars exploration would involve about half a dozen of these robotic excursions. The United States and the Soviet Union could jointly lead the world in such a

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

project. Each would conduct three coordinated excursions. Planning and scientific investigations could be carried out in close cooperation. There would be ample opportunity for other nations to participate.

This approach, increasing cooperation substantially but stopping short of fully joint missions for now, would allow the two superpowers to begin immediately a project of historic importance on behalf of the whole human race. Both nations would achieve economies and would accomplish scientific objectives of global importance. They also would begin to build the experience, knowledge and trust that could foster even closer cooperation in the future.

June 10, 1990

Eugene H. Levy is head of the planetary sciences department at the University of Arizona, Tucson.

* * *

The Less-Noticed Worldwide Revolution

Peter H. Raven

Many parents across the country reportedly have been stunned to discover that their teenagers are baffled about the significance of events in Eastern Europe and the Soviet Union over the past several months. How, these parents wonder, can young people be so ignorant about such historic occurrences?

I share their concern, but I think many parents are as culpable as their children when it comes to awareness of another, equally important upheaval taking place in the world today. I refer to the revolution in biology, which is likely to

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

change the course of human history as profoundly as anything in today's political arena.

The recent transformation of the biological sciences is comparable to the tumult that occurred in physics earlier this century with Albert Einstein and others or in astronomy at the time of Galileo. When one considers the impact those two earlier upheavals had on subsequent history—on politics, warfare and other events far beyond the world of science—it is not an overstatement to describe current advances in biology as among the most consequential developments of modern times.

During the past two decades, biology has been transformed from a collection of single-discipline endeavors to an interactive science of extraordinary vitality. Starting with the establishment of the structure of DNA and continuing with the demonstration that genes could be modified and moved from one organism to another, the flow of biological discovery has swelled from a trickle to a torrent. Advances have followed rapidly from new methodologies, such as the use of recombinant DNA, monoclonal antibodies, microchemical instrumentation and computers.

A complete understanding of living systems at the molecular level now seems to be at hand. As a team of more than 100 scientists that I led for the National Research Council concluded recently, modern biology is poised to make fundamental discoveries critical to understanding how humans resist infection, how a fertilized egg develops, and how humans dream, imagine and reason. Researchers are revealing the mechanisms underlying simple forms of learning and short-term memory. They are using sophisticated molecular and genetic techniques to analyze genetic differences between species, clarifying how life on Earth emerged.

Many of these secrets of nature are so fundamental that uncovering them could affect our human self-image as deeply as did Copernicus' revelation five centuries ago that the Earth revolved around the Sun, rather than vice versa.

The ''new biology'' clearly is of immense importance to the U.S. economy. Technologies based on biology will provide the basis for advances not only in predictable fields such as pharmaceuticals, but in a wide range of manufacturing

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

and service industries. Companies throughout the United States, Europe and Japan have begun making major investments in new products based on genetic engineering, fermentation and other biological applications. Our country will have no choice but to compete vigorously in this new arena.

In health care, new biological information promises to make possible significant advances through new therapeutic drugs and improved methods of diagnosis for AIDS, cancer, Alzheimer's disease and other ailments. In agriculture, farmers will control pests increasingly through biological techniques rather than with chemicals, increasing their profits while providing healthier food and a safer environment.

At such a historic juncture, it is ironic that the United States faces a projected shortage of biology researchers and trained technical experts and that many U.S. universities and research centers require better facilities and instrumentation to carry out world-class research. The future of biology also is clouded by the rapid extinction of plant and animal species occurring around the world as human populations expand and natural habitats are destroyed. Each form of life that disappears takes with it a pattern of gene expression that evolved over millions of years, destroying a piece of the foundation upon which all of biology is built. This priceless worldwide genetic heritage must be protected.

It would be a tragic squandering of opportunity if inadequate resources and the destruction of species were allowed to slow the pace of continued biological discovery. Just as recent events in the communist world have reshaped the world's political landscape, the biological revolution has the capacity to transform our lives in extraordinary, if unpredictable, ways. It is a revolution whose reverberations will be felt even by people who now are oblivious to its occurrence.

April 29, 1990

Peter H. Raven is director of the Missouri Botanical Garden.

* * *

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Searching for Buried Treasure

Charles A. Bookman

In an era when our nation has sent explorers to the moon, probed the planets and is considering a manned voyage to Mars, another frontier much closer to home lies largely unexplored. This prize, containing billions of dollars in resources, is our national seabed. The United States has barely begun to capitalize on the plants, animals, minerals, recreational opportunities and other riches lying off its shores.

In 1983, President Reagan established the 200-mile zone beyond the coastline that is now under our national jurisdiction. However, this 3.9 billion acres of ocean territory has yet to be explored systematically. No single federal body coordinates the often conflicting interests of private companies, universities, the military, states, cities, federal agencies and others who have an interest in this natural underwater treasure chest.

As an expert committee of the National Research Council urged in a report recently, the federal government needs to develop a coherent national policy to analyze the seabed more thoroughly as a first step to putting it to better use.

Ocean businesses already contribute 1.7 percent to our country's gross national product. In 1987, this amounted to $76 billion, mostly from fishing and offshore oil and gas drilling. The importance of fishing is apparent to consumers, and the substantial U.S. dependence on offshore drilling is certain to expand as onshore resources are exhausted.

Yet the seabed offers more than fish and fuel; it also is a trove of minerals. Off Alaska, miners extract gold from the ocean floor. In the central Pacific off Hawaii, potato-sized nodules rich in strategically important minerals await harvesting. Within the continental United States, offshore sand and gravel deposits are occasionally tapped to control beach erosion or for other construction purposes. While most ocean minerals will not be mined until prices improve, the United States would benefit immediately from a clearer picture of its holdings

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

of critical minerals such as cadmium and cobalt, for which it now is overly dependent on a few foreign countries.

The oceans also are essential to the world's communications systems. With the rapid development of fiber-optic technology, underwater cables have replaced satellites as the transoceanic medium of choice. Half of all overseas calls are now transmitted through cables. Our armed forces rely on the oceans as an operational area for submarines, monitoring and listening systems, and anti-submarine and mine warfare.

Other ways of using the seabed have been tried or suggested, as well. More than 750,000 tourists have ridden to the sea floor during the past few years in specially designed submarines, mainly in shallow water at tourist resorts in the Virgin Islands, Hawaii and other places. It does not take much imagination to envision excursions to the growing number of marine sanctuaries and memorials, such as the sites of the Monitor and the Titanic.

Our oceans also could be used for farming and for energy systems. Hawaiian farmers already are using nutrient-rich seawater to help grow giant strawberries and other products. Energy innovators are studying ways of harnessing the heat differential between land and sea to generate electricity or of using cold seawater to produce air conditioning for seaside buildings. Still another possibility is to use the seabed as a site for unwanted urban wastes. Sewage sludge might be placed beneath the seabed and isolated with clean sand.

Ideas such as this last one require considerable study to guard against environmental or other problems, but the general concept of using our oceans more imaginatively clearly deserves closer consideration. President Bush and Congress have an opportunity to launch a major exploration of the nation's last frontier, much as President Thomas Jefferson authorized the Lewis and Clark expedition to investigate the American West nearly two centuries ago. Such a mission would expedite exploration of the seabed, head off potential conflicts among users and perhaps even capture the imagination of the public. It would be most valuable if a special commission also were established to determine priorities for seabed exploration and development and to generate needed technology.

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

As the Research Council committee pointed out, our seabed is a national treasure of unprecedented dimensions, one whose resources are barely tapped. It will require consider able cost and long lead times to make the most of this bounty, but the benefits to the nation will be substantial.

March 4, 1990

Charles A. Bookman is the director of the Marine Board of the National Research Council.

* * *

The Energy Crisis Beyond the Persian Gulf

David L. Morrison

Fifty years from now, when Saddam Hussein is just a bad memory, Americans could face an even worse predicament. This potential danger will be affected directly by actions we take in response to the Persian Gulf crisis.

This longer-term threat is not military but environmental: global warming and climatic change. Scientists are still studying the likelihood and possible extent of such changes, but warming of the Earth could have a devastating impact on the world of the future. Some plausible scenarios foresee a rise in sea level, reduced agricultural productivity and millions of environmental refugees.

During the past five years, with gas prices so cheap, Americans showed little interest in energy policy. Now policymakers are scrambling to reduce oil imports and promote use of domestic energy sources. Additionally, we must seek to reduce our consumption of fossil fuels to ease the threat of global warming. Both goals can be achieved by moving faster

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

to improve our nation's energy productivity and to adopt alternatives such as biomass fuels and solar-powered photovoltaics, recycling technologies, more efficient buildings and transportation systems, and better methods of storing electricity.

These and other alternatives have languished over the past decade. During the 1980s, federal funding of the Department of Energy's (DOE) civilian research and development program on solar and renewable resources plunged by nearly 90 percent. DOE research on energy conservation declined by 61 percent, and research by private companies also fell.

Although the nation cannot invest in every alternative, some deserve closer consideration. At DOE's request, a committee of the National Research Council, which I chaired, recently identified several that look especially promising on both environmental and economic grounds.

For example, cars and light trucks are a major source of the excess carbon dioxide in our atmosphere. The average fuel efficiency of new cars in the United States is only 28 miles per gallon. With stringent government policies and a greater effort by industry, this probably could be raised to 45 miles per gallon within a decade. Another goal should be to improve batteries to provide motorists with electric cars that offer better performance at lower costs without the emissions.

Energy use and greenhouse gas emissions in our residential and commercial buildings can be slashed by more than 70 percent with improved materials for walls, windows and roofs; more efficient heating systems, air conditioners and lights; and other strategies.

Research also should be focused on coal-fired generators, which produce more than half of the nation's electric power and most of its acid rain. With existing technology, sulfur dioxide emissions can be reduced to ease acid rain—but at the price of lower efficiency. As a result, more plants are needed and more carbon dioxide may be produced. Rather than pursuing tradeoffs between two undesirable kinds of emissions—sulfur dioxide and carbon dioxide—we should find ways to reduce both while increasing efficiency.

Renewables also deserve more attention. The price of

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

electricity produced by photovoltaic modules has plummeted since the early 1970s but still exceeds the cost of power from public utilities. Manufacturing research could bring down the price of such renewable technologies.

If budget constraints prevent increased funding for this kind of research, DOE should consider scaling back some magnetic fusion research. Commercially viable fusion reactors are highly unlikely to make any significant additions to the U.S. electricity generation mix before the year 2050. Efforts in this field should shift towards more basic research and greater international collaboration. This would free up funds for research that promises a more immediate and lasting energy payoff.

Obviously, research alone cannot ensure energy security or protect the environment. Changes in public policies, such as new tax credits or stricter energy efficiency standards, should be considered as well. In addition, the government might stimulate consumers to adopt more efficient home furnaces and other underused technologies.

DOE now spends $2.2 billion annually on civilian energy research and development, and it may well spend more before the dust settles in the Persian Gulf. This effort should be applauded—and expanded. It also should be crafted in a way that will serve us well, not only through today's crisis but in the uncertain climate of the future.

September 16, 1990

David L. Morrison is technical director of the energy, resource and environmental systems division at MITRE Corp., in McLean, Va.

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Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

The Challenge to Human Uniqueness

Herbert A. Simon

The rapid development of artificial intelligence in computers is about to challenge our sense of human uniqueness as profoundly as anything since the days of Copernicus or Darwin.

At one time, We might remember, human beings thought they had been placed in the geometric center of the universe. Then Copernicus came along and said we humans had it all wrong, that we really live on a planet circulating around the sun. So mankind had to develop a new sense of its uniqueness that no longer relied on being physically at the center of things.

Next came Darwin. He pointed out that we had been resting our notions of uniqueness on the idea that we are a specially created species unlike any other. Darwin showed that the human species evolved through processes of mutation and selection just like all the others. So now mankind had to give up its notion of uniqueness not only in the universe, but among species.

Nevertheless, we humans have continued to think of ourselves as unique in the years since Copernicus and Darwin. Why? In considerable part because of our capacity to think and reason. Other animals also think, of course, but we are seemingly the only ones who can think complex thoughts, abstract thoughts, thoughts involving the use of language.

Developments in artificial intelligence, the study of computers doing intelligent things, are now challenging this aspect of uniqueness.

What do we mean by intelligence? How do I know that a person is thinking? I can check whether the person has a studious frown on his face as he ponders a problem, of course, but that is not very reliable evidence. The only empirical way to decide is to give a person a task and then judge on

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

the basis of his or her performance whether a thought has taken place in reaching a solution.

It is only human chauvinism to refuse to call something non-human, such as a computer, intelligent if it does the same. Computers today now play chess just below the grandmaster level. They can examine data and discover scientific laws. A program called BACON that I helped develop was given the distances of the planets from the Sun and their periods of revolution. It discovered in less than a minute that the periods vary as 3/2 powers of the distances. This is Kepler's Third Law, an important discovery of the 17th century. Other computer programs are diagnosing medical illnesses, prospecting for ore and synthesizing chemical reactions.

True, computers have not yet been able to write good poetry or great music, or to solve certain kinds of analytic problems. Large areas of human thought processes still have not been explored. Nonetheless, having worked with artificial intelligence for almost three decades, my bet is that every kind of human thinking will eventually be able to be performed by non-human systems.

It is significant in this regard that robotic devices for use in variable physical environments have proven much more difficult to develop than computers that mimic abstract human thought. One reason is that higher human cognitive skills have been evolving for only a couple of million years, whereas our sensory and motor skills evolved over 400 million years and therefore are more sophisticated and harder to replicate. Given how proud we are of our intelligence, it should give us pause to remember that it's easier to automate a professor than a bulldozer driver.

What are the likely implications for human society of these developments in artificial intelligence?

One of the most encouraging possibilities concerns education. Much teaching today is inefficient, largely because it is based on remarkably little fundamental understanding about how a student's brain processes knowledge. New insights from artificial intelligence and related fields may enable us to revolutionize education, much as medicine was transformed

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

when researchers finally began to understand the biological bases of disease.

Increased knowledge about ourselves also should help us to become better problem-solvers and decision-makers. The threat of nuclear war, stress on the environment, scarcity of resources and other problems in the world today are caused ultimately not by technology, but by ourselves. We will solve these problems only when we learn to improve the use we make of our own minds.

Most important is how we will change our image of ourselves and our sense of place in the universe. It is important to recall that most people did reconcile themselves to the discoveries of Copernicus and Darwin, and did not feel any the worse for it. One can have confidence that people in the future also will find a way to describe their place in the world without having to believe that they are unique as thinkers.

Mankind's development of a new self-concept is likely to be as valuable as any specific benefits that it will gain from computers themselves. It is ironic, perhaps, but the ultimate benefit of our search for smarter machines may well prove to be this deeper knowledge of our own thinking and of ourselves.

June 23, 1985

Herbert A. Simon, winner of the Nobel Memorial Prize in Economic Science, is a professor of computer science and psychology at Carnegie Mellon University.

* * *

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Making a Map of the Human Chromosomes

Bruce M. Alberts

Imagine you are an ambulance driver and someone's life depends on your finding an address—but you have no map. That's the dilemma faced by medical researchers, who must search for the cures to serious genetic diseases without knowing where the relevant genes are located on the human chromosomes.

The result is that research today proceeds much more slowly than it might on heart disease, cancer, certain kinds of Alzheimer's disease, cystic fibrosis and some 3,000 other disorders with a genetic component. Researchers must spend vast amounts of their time and resources searching again and again for genetic needles in the haystack of the human chromosomes; a typical set of chromosomes holds about 100,000 genes, of which fewer than 1,500 have been charted.

Like the ambulance driver searching blindly along city streets, these researchers could do their work far more effectively—and save many more lives—if they had a decent road map. Fortunately, that is now possible. An expert committee of the National Research Council, which I chaired, concluded recently that it has become feasible to map all the genetic material in the human chromosome, which scientists refer to as ''the human genome.''

Our committee, which included two Nobel laureates and a number of the world's leading biologists, urged the federal government to launch a program to create such a genetic map. The project, the largest research effort with a defined focus ever undertaken in biology, would greatly increase our understanding of the human organism and promote rapid progress in controlling many diseases.

The human body is extraordinarily complex, containing about 10,000 billion individual cells. Each cell carries a complete set of genetic blueprints for the entire body. These blueprints are stored as DNA, a molecule that when highly

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

magnified looks like a very long and thin twisted rope ladder. A single DNA molecule forms each human chromosome, containing the genes that determine everything from the color of a child's eyes to the likelihood of an adult's suffering from certain forms of manic depression.

The goal of mapping the human genome is to identify the location of all the genes on each chromosome, which is to say on the DNA molecules. A genetic map would not cure genetic diseases by itself; it would only be a tool to help researchers analyze these diseases in their laboratories. Yet its value would be incalculable, like trading in the maps of Columbus for detailed satellite photos. Locating desired genes is essential because it leads directly to the discovery of the molecules that cause genetic diseases.

Scientific expertise in gene mapping is still in its adolescence, although major advances have been made in the past few years. Therefore, a major priority in the near future must be to develop more powerful techniques. Our committee decided that the best way to accomplish this would be to divide the task among competing research teams around the country, with each team using its own techniques to map a large amount of DNA. The techniques could then be compared and the best ones selected for further use.

We estimated that several types of detailed maps of the entire human genome could be completed within five to ten years. However, the most detailed description is much more difficult to obtain. It would give the chemical composition of all the chromosomes, showing the exact order of the subunits, or nucleotides. There are about three billion of these subunits in the human genome, arranged in a precise order like beads in a necklace. A technique called "DNA sequencing" allows this order to be determined.

One way to understand the difference between mapping and sequencing is to think of a giant library. Mapping is like noting the titles and order of all the books on the shelves; sequencing means actually reading the books.

With present techniques, it would take an estimated 30,000 "person years" of labor to obtain all of this sequencing information. Rather than attempt such a costly project now, our committee recommended the immediate support of many

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

competing efforts to improve sequencing methods and lay the groundwork for a full-scale sequencing effort.

We urged that new funds be provided for a special "human genome project," costing about $200 million annually for 15 years and including both mapping and sequencing. The funds would go primarily to individual investigators and small centers, with scientific oversight by an independent board of leading scientists. A central data bank and stock center also would be needed to gather and share all the information among the research teams.

The cost of this project would be about 3 percent of current federal spending on basic biology research. Our committee considered that to be a price well worth paying. Mapping and sequencing the human genome would create a tool of fundamental value, providing researchers with the "dictionary" they need to speed future medical advances.

March 20, 1988

Bruce M. Alberts is professor of biochemistry and biophysics at the University of California, San Francisco.

* * *

Developing New Contraceptive Options

Luigi Mastroianni, Jr.

Birth control pills, condoms, intrauterine devices (IUDs), diaphragms, contraceptive sponges, foams and other vaginal contraceptives, and natural birth control methods are the options available to couples in the United States who wish to practice contraception.

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

These choices are inadequate. In some European countries, couples also can choose among contraceptive implants; injectable contraceptives; and a variety of pills, IUDs and sterilization techniques not offered in the United States. For example, an implant placed under a woman's skin that releases progestin has been available in Europe, Asia and Latin America for the past decade but only recently has received serious consideration in the United States.

An expert committee of the National Research Council and the Institute of Medicine reported this past week that U.S. consumers not only cannot obtain useful contraceptives available in other parts of the world but also may miss out on technologies still in development. These include a contraceptive vaccine, improved techniques of reversible male and female sterilization, a once-a-month pill that induces menses, and methods that interfere with sperm production.

Since the introduction of the pill and the IUD in the early 1960s, no fundamentally new contraceptive methods have been approved for use in the United States. Only one large U.S. pharmaceutical company still maintains a significant contraceptive research program, although some smaller firms and non-profit organizations have stepped up their research efforts.

One might attribute this slow progress to a lack of interest among potential users. However, of the 54 million U.S. women between the ages of 15 and 44 who have had intercourse, 95 percent have used contraception at some time. Many of them—and their male partners—are dissatisfied with the choices obtainable from physicians and pharmacies. Contraceptive failure is common, and unwanted pregnancies lead often to abortion.

Both women and men need new methods to meet their contraceptive needs as they pass through the stages of their reproductive lives. A given method may be most appropriate for young people and for those having intercourse only occasionally, while another method may be better suited to mothers who are breastfeeding and want to space their pregnancies. An increase in the number and type of contraceptive options also would ease important social problems, such as

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

teenage pregnancy, abortion and the spread of sexually transmitted diseases.

The current situation results from many causes, but our committee identified two ways of easing it considerably. First, the Food and Drug Administration (FDA) should adopt a more realistic method of evaluating new contraceptives. For most other drugs and devices, the FDA weighs the risks and benefits for a specific group of users, such as patients with cancer or diabetes. When it comes to contraceptives, however, the FDA assesses the potential impact on healthy users rather than considering the special needs of nursing mothers, older women who smoke, and other inadequately served groups. More weight should be given to these variations among potential users.

The FDA also should strengthen its current emphasis on safety by paying greater attention to the effectiveness and convenience of different methods. Methods such as spermicidal jellies and foams are not necessarily safer if they have higher failure rates, especially given the potentially serious health consequences of unwanted pregnancies in some circumstances. Modifying the approval process could make more products available while maintaining rigorous safety standards.

Our other main recommendation dealt with liability laws. Recent product-liability litigation and rising insurance rates have been a major obstacle to contraceptive development. Many pharmaceutical companies view the current situation as so unpredictable that they are unwilling to make costly investments in new products. Our committee concluded that the rules could be changed to ease their concerns without increasing the risks to consumers.

At the least, Congress should enact a statute that gives companies some legal protection when they follow FDA guidelines faithfully in producing a product. If it turns out later that unforeseen and unforeseeable complications occur, the companies should not be held responsible unless it is shown that they willfully withheld relevant information.

These two steps would go a long way toward meeting the public's demand for safer, more effective, more convenient and affordable contraceptives. Unless action is taken to change public policy, contraceptive choices in the United

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

States in the next century will not be appreciably different from what they are today.

February 18, 1990

Luigi Mastroianni, Jr., director of the division of human reproduction at the Hospital of the University of Pennsylvania, headed a committee of the National Research Council and the Institute of Medicine that studied contraceptive development.

* * *

Farewell to the Night Sky

David L. Crawford

A priceless part of our human heritage is fading into the night sky.

Most Americans are growing up unable to see the stars their grandparents knew so well. They see the night sky only in pictures or at planetariums. This is true not only in cities but also in many suburbs where street lamps and other sources of "light pollution" have obscured our view of constellations, meteor showers and planets.

Indeed, many youngsters may now say, after viewing the night sky in a rural area for the first time, that "it looks just like the planetarium."

Light pollution is not a matter of life and death. Yet it is important nonetheless, profoundly so. We human beings lose something of ourselves when we can no longer look up and see our place in the universe. It is like never again hearing the laughter of children; we give up part of what we are.

Such a loss might be acceptable if light pollution were the inevitable price of progress. But it's not; most sky glow, as scientists call it, is unnecessary. The light that obscures

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

our view of the night sky comes mainly from inefficient lighting sources that do little to increase nighttime safety, utility or security. It produces only glare and clutter, costing more than a billion dollars annually in wasted energy in the United States alone.

For science, the impact has been even more tangible and adverse. Astronomers require observations of extremely faint objects that can be made only with large telescopes located at sites free of air pollution and urban sky glow. For example, scientists interested in how the universe was formed may study the light of galaxies and quasars located incredibly vast distances from Earth. These images offer information about faraway corners of the universe, helping us understand how our own world was formed. Yet, after traveling countless light years, the light from these objects can be lost at the end of its journey in the glare of our own sky.

Space-based telescopes, such as the Hubble Space Telescope, offer one way around the problem. However, large telescopes here on Earth will always be used, if only because they are accessible, cost much less than orbiting devices and can do many jobs more cheaply.

In fact, our experience over the past two decades has shown that space-based astronomy, far from reducing the need for ground-based observations, actually increases the demand for these facilities. New telescopes now planned or under construction here on Earth will complement the knowledge we gain from telescopes in space—but only if they are not compromised by encroaching light pollution, as has occurred near Mount Wilson, near Los Angeles and several other older observatories.

Reducing light pollution is not difficult, but it does require that public officials and ordinary citizens be aware of the problem and act to counter it. Low-pressure sodium lights, for example, can replace existing fixtures for most streets, parking lots and other locations. They reduce glare and save money.

Another fairly painless way to reduce light pollution is with outdoor lighting control ordinances, over 50 of which have been enacted throughout Arizona and in several key cities and counties in California and Hawaii. These measures typically require communities to prohibit inefficient,

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

low-quality lighting. Not only do they help preserve dark skies, but they also enhance energy efficiency. An outdoor lighting system recently installed at a prison in Arizona, for example, improved security and reduced light pollution while cutting energy costs by 50 percent. There is no reason that all communities should not have such efficient lighting.

On an individual level, people can help reduce sky glow by using night lighting only when necessary, choosing well-shielded light fixtures, and turning off lights when they are not needed.

Curing light pollution saves money while reducing glare. Unlike other issues involving pollution, it presents us with a rare case where we should strive to be "kept in the dark." The stars above us are a priceless heritage—not only for scientific knowledge, but also for our identity as human beings.

More of our children—and their children—should be able to look up at night and see that the Milky Way isn't only a candy bar.

December 3, 1989

David L. Crawford, an astronomer at the Kitt Peak National Observatory in Tucson, is executive director of the International Dark-Sky Association.

* * *

Setting Our Science Priorities in Order

Frank Press

Science and technology present the Bush administration with some of its best opportunities to leave its mark on history. The super collider, a program to map the human

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
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genome, the space station, a new AIDS initiative, and increased research on environmental problems and superconductivity are among the many possible initiatives that could change our world profoundly.

Yet, even as investments in science and technology offer greater promise than ever before for producing significant benefits in health, the environment and other fields, the United States faces unprecedented budget deficits. How, then, is it to pursue these new opportunities while also providing adequate support to smaller-scale research, science education and other activities that are less visible but of equal, if not greater, importance?

That is a dilemma facing the new president and Congress, and it is made more difficult by the inadequate system now in place to make federal budget decisions about science and technology. Although effective in the past at helping the United States assume world leadership in these fields, the system is unable to provide us with clear national priorities in the face of these historic opportunities and constraints.

The system does do a good job of setting priorities within specific agencies involved in science, but not when it comes to looking across agency lines and establishing priorities overall. Both the executive branch and Congress are left focusing on the trees instead of the forest.

For example, when researchers in Zurich announced in late 1986 that they had discovered materials that become superconductive at much higher temperatures than anything recorded previously, they set off an international race to develop new applications and industries. Officials in Washington soon began asking what the United States was doing in the field, only to discover that the federal effort was split among five agencies with no capacity for overall assessment in place. In the end, Congress had to create a special commission to provide direction.

Similarly, federal efforts to understand global warming and other kinds of climate change are now divided among the Environmental Protection Agency, the Department of Energy, the National Science Foundation, the National

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

Aeronautics and Space Administration, the Department of Agriculture and the National Oceanic and Atmospheric Administration, among other agencies. Such a multiplicity of efforts has many benefits, but it should not be as difficult as it is to find out what the government is doing overall about climate change.

The federal government now spends more than $60 billion annually on science and technology activities, and it needs to allocate the money more effectively. At congressional request, the National Academy of Sciences, the National Academy of Engineering and the institute of Medicine recently offered some suggestions on how this might be accomplished.

Our basic message to both President-elect Bush and the Congress was the same: Set clearer priorities before dividing the budget pot among the different agencies. Specifically, we said the president should establish overall goals in science and technology that individual agencies can use as guidelines in preparing their own budgets. Congress should follow a similar process.

These goals should be set not only along traditional agency lines, but also in terms of how they will contribute to the nation's underlying science and technology base—its work force and research facilities—or to broad national objectives, such as industrial competitiveness and environmental protection. Major initiatives such as the space station may need to be considered as a separate category.

A greater effort should also be made to distinguish between military and civilian research in the budget. Much military research has limited application to the civilian sector, and lumping the two together tends to overstate the true size of the U.S. science and technology enterprise. Reforms like these do not alter the traditional prerogatives of government officials. Nor do they lead to a centralized science bureaucracy, which might threaten the flow of unconventional ideas that are so essential to the scientific process.

Instead, rationalizing the budget process in this way will help officials see the "big picture" on questions as vital as AIDS, the space program, the global environment and

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
×

agriculture. They will become better able to put science and technology to work to solve the problems that lie ahead for our nation not only over the next four years, but in the decades to come. Science, of all pursuits, ought to be handled more rationally.

January 10, 1989

Frank Press is president of the National Academy of Sciences.

Suggested Citation:"6 Scientific Horizons." National Academy of Sciences and National Research Council. 1991. Headline News, Science Views. Washington, DC: The National Academies Press. doi: 10.17226/1575.
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Many Americans want information on how to eat a healthier diet, clean up the environment, or improve their children's education. Yet, all too often, people lack the time or background to read scientific reports for answers to these questions.

Now, scientists and nonscientists alike will enjoy Headline News, Science Views, a collection of easy-to-read short articles on many of today's most important issues.

These readable essays are written by some of the country's leading scientists, engineers, physicians, and other experts. The authors discuss intriguing issues in language that is understandable and compelling...without jargon. Celebrity Bill Cosby contributes an essay on "Getting the Facts Straight About Science." Television journalist Hugh Downs asks "Who Owns Antarctica?"

Readers learn the many ways in which science and technology affect their daily lives.

This volume makes groundbreaking scientific achievement accessible, fascinating--and fun. Bridging the gap between the experts and the public, it is a "must read" for anyone concerned about the future.

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