Skip to content

Choose a Chapter below or view the Sitemap

Unit 1:
Ch. 1
Ch. 2
Ch. 3
Interlude A
Unit 2:
Ch. 4
Ch. 5
Ch. 6
Ch. 7
Ch. 8
Ch. 9
Interlude B
Unit 3:
Ch. 10
Ch. 11
Ch. 12
Ch. 13
Ch. 14
Ch. 15
Interlude C
Unit 4:
Ch. 16
Ch. 17
Ch. 18
Ch. 19
Interlude D
Unit 5:
Ch. 20
Ch. 21
Ch. 22
Ch. 23
Ch. 24
Ch. 25
Ch. 26
Ch. 27
Ch. 28
Ch. 29
Ch. 30
Interlude E
Unit 6:
Ch. 31
Ch. 32
Interlude F
Unit 7:
Ch. 33
Ch. 34
Ch. 35
Ch. 36
Ch. 37
Ch. 38
Interlude G

» Getting Started » A Guide to the Reading » Tying it all together

Getting Started

Below are a few questions to consider prior to reading Interlude F. These questions will help guide your exploration and assist you in identifying some of the key concepts presented in this chapter.

  1. How much daily caloric intake does a human require to remain healthy?
  2. What six crops are responsible for more than 80 percent of the calories eaten by humans?
  3. What is the status of the three traditional systems of food production?
  4. What systems of managed food production are now supplementing the traditional systems?
  5. What is the approximate number of people living today that suffer from problems related to food shortages?
  6. Are food shortages strictly a biological problem that science has the best potential to solve?
  7. What are genetically modified crops?
  8. Why does preserving the world’s biodiversity improve the potential of ending world hunger?
  9. What changes must occur before world hunger will be eliminated?

A Guide to the Reading

When exploring the contents in Interlude F for the first time, the following concepts typically give students the most difficulty. For each concept, one or more references have been identified which may help you gain a better understanding of these potentially problematic areas.

Meeting the Need for Animal Protein

Protein from animal products currently accounts for about 30 percent of the protein consumed by people. Traditionally, two food systems, rangelands and oceanic fisheries, have provided this protein. Both systems show signs of having reached their production capacities, and per person production for beef and seafood has been declining. Future increases in animal protein will come from highly managed systems like aquaculture and feedlots if the environmental problems they cause can be solved. Concentrating large numbers of animals in small spaces creates large amounts of pollution. The primary issue surrounding animal production is that the foods given to animals are often suitable for people. Future improvements in the production of animal protein will find ways to use those portions of a crop that are not consumed by people. Examples include using corn stalks, rice straw, and wheat straw as animal feed.

For more information on this concept, be sure to focus on:

  • Interlude F, Three Traditional Food Systems
  • Interlude F, Meeting the Need for Animal Protein
  • Table F.1, Food Production from the Three Traditional Food Systems

Steps to End World Hunger

Approximately 80 percent of human calories come from plant material. Ending hunger will only be possible by increasing the production of croplands. Agricultural productivity has been increasing steadily for the past 300 years. During the past 50 years, efforts known collectively as the Green Revolution produced tremendous improvements in yields. These gains, however, have not been without costs. Chemical pesticides result in environmental pollution. Irrigation slowly increases the saltiness of the soil. Intensive cultivation practices accelerate soil erosion. Of greater concern is the fact that the fundamental human problems that aggravate hunger — poverty, lack of education, uncontrolled population growth, war, and corruption  — persist. Fortunately, these problems are not insurmountable. In just 15 years Thailand has made significant gains in reducing malnutrition by addressing social issues like education along with agricultural improvements. Although some countries may be able to improve the conditions for their citizens, not all nations have the same potential for food production. A lasting solution to world hunger will be global rather than regional. Improving the distribution of food and increasing the access of poor farmers to world markets is also necessary. Many countries, however, impose barriers on trade that protect their own farmers while harming those in other countries. Political solutions as well as biological ones will be necessary.

For more information on this concept, be sure to focus on:

  • Interlude F, Steps to End World Hunger
  • Figure F.5, The Hunger Map

Improving Existing Crops

Increasing crop production is conceptually simple: increase the yield of a crop or increase the area being farmed. Unfortunately, the most suitable farmland is already in use. Some marginal lands could be developed but the productivity of marginal areas declines quickly as erosion and nutrient depletion reduce soil fertility. Natural areas not currently farmed, like tropical rain forests, make essential ecological contributions to the planet and must be preserved. Thus future improvements will involve increased yields. One promising approach is genetic engineering. Termed genetically modified (GM) crops, varieties can be engineered to resist virus or insect attack, tolerate exposure to herbicides, or use water more efficiently. To date, few GM crops have specifically addressed human nutrition, but the potential for increasing protein, vitamin, or mineral content, for example, suggests the process will be an important part of the solution to world hunger.  GM crops have been widely accepted in parts of the world, and heavily criticized in others. Many communities have made efforts to ban the sale of GM products. An alternative to improving crop varieties is plant breeding. Through selective breeding, highly inbred varieties can be crossed to produce hybrids, which often have higher yields. Selective breeding and genetic engineering are only possible because of the natural genetic diversity that exists among the world’s crops. Scientists are concerned by the trend to plant vast areas with crops that have little genetic diversity. In the short term, the practice is beneficial. The crop matures at the same time, and the produce (an ear of corn, for example) is uniform in size and easily managed by a harvesting machine. In the long term, such practices will probably prove to be detrimental. As genetic uniformity increases, aspects such as disease or pest resistance become uniform as well. A new pest or disease could devastate world production of one of the basic crops. Preserving genetic diversity is a vital aspect of reducing world hunger.

For more information on this concept, be sure to focus on:

  • Interlude F, Improving Existing Crops
  • Figure F.8, A Panoply of Genetically Modified Crops

Protecting the Global Environment

Agriculture is believed to have developed about 10,000 years ago; it is a human invention rather than a natural process. As such, agriculture has an impact on the environment. The extent of that impact varies widely. Some types of agriculture, when done on marginal lands, may damage the land so extensively that it must be abandoned.  Fortunately, the impact of most agriculture is less dramatic, but, nevertheless, still environmentally harmful. Even the most benign aspects of agriculture oppose natural systems. Plowing disrupts the soil; weed and pest suppression introduces toxic chemicals, and irrigation adds salts to the soil. To end hunger, people must find ways to make their lifestyles sustainable. Many current practices use resources more rapidly than they can be replenished. Analytical models suggest that world hunger could be eliminated in 50 to 60 years provided we make the choices needed to protect the environment and implement policies that benefit rich and poor alike.

For more information on this concept, be sure to focus on:

  • Interlude F, Protecting the Global Environment
  • Interlude F, Can We End Hunger in Our Lifetime?
  • Figure F.12, How Farm Ecosystems Work

Tying it all together

Several concepts presented in this chapter build upon concepts presented in previous chapters and are also revisited and discussed in greater detail in subsequent chapters, including:

Meeting the Need for Animal Protein

  • Chapter 21 – Section 21.1, Nutrients That Animals Need
  • Chapter 38 – Section 38.1, Land and Water Transformation

Steps to End World Hunger

  • Chapter 31 – Section 31.4, How Plants Obtain Nutrients
  • Chapter 34 – Section 34.6, Human Population Growth: Surpassing the Limits
  • Chapter 38 – Section 38.2, Changes in the Chemistry of Earth

Improving Existing Crops

  • Chapter 15 – in Section 15.3, Genetic engineering is used to transfer genes from one species to another
  • Chapter 32 – Section 32.2, How Plants Grow: Primary and Secondary Growth

Protecting the Global Environment

  • Chapter 36 – Section 36.3, Recovery from Disturbance
  • Chapter 38 – Section 38.1, Land and Water Transformation
  • Interlude G, Applying What We Learned: Building a Sustainable Society

Chapter Menu

Other Resources

Norton Gradebook

Instructors now have an easy way to collect students’ online quizzes with the Norton Gradebook without flooding their inboxes with e-mails.

Students can track their online quiz scores by setting up their own Student Gradebook.