Agriculture LESSON 3 Guiding Question: How has agriculture evolved? • Discuss the beginnings of agriculture. Reading Strategy As you read, fill in a main idea and • Explain the importance of industrial agriculture and details chart. List the main ideas of the lesson in the left col- the green revolution. umn. In the right column, note important details about each • Identify different types of pest control. main idea. • Explain the importance of pollinators to agriculture. Vocabulary traditional agriculture, yield, industrial agriculture, green revolution, biological pest control, integrated pest management (IPM), pollinator CAN YOU IMAGINE having to hunt and gather your own food every day? Can you imagine life without cotton? That was life 15,000 years ago. Agriculture arose only about 10,000 years ago. Many aspects of human 12.3 LESSON PLAN PREVIEW civilization began about the same time. That is probably not a coinci- Inquiry Students investigate dence. Walking around all day hunting and gathering didn’t leave much agricultural advances through- time for creating art or new technology! out history. Real World Students find ex- amples of chemical pesticide use Development of Agriculture in their environment. Agriculture began about 10,000 years ago, when a warmer Differentiated Instruction climate enabled humans to plant seeds and raise livestock. English language learners study word parts to understand the Everything you eat and all the natural fabrics you wear are products of terms pollination and pollinators. agriculture. If you don’t run a farm, you rely on people who do. But agri- 12.3 RESOURCES culture is a relatively new development in human history. In Your Neighborhood Activity, Local During most of the human species’ 200,000-year existence, we have Planting Conditions • Map It Online • been hunter-gatherers, depending on wild plants and animals for our Lesson 12.3 Worksheets • Lesson 12.3 food and fiber. Then about 10,000 years ago, the climate warmed follow- Assessment • Chapter 12 Overview ing an ice age. In the warmer climate, plants grew better. People in the Presentation Middle East, China, and other areas began to grow plants from seed and to raise animals. FIGURE 12 Early Farming Tools The blades in this photo were used to Agriculture probably began when hunter-gatherers harvest crops about 5000 years ago. brought wild fruits, grains, and nuts back to their camps. Some of these foods fell to the ground, were thrown away, or were eaten but had seeds that passed through someone’s digestive system. The plants that grew from these seeds likely produced fruits larger and tastier than most, because they came from seeds of fruits that people had selected. As these plants bred with others nearby that shared those characteristics, they produced new generations of plants with large and tasty fruits. You can see more details of the evolution of agriculture in Figure 13 on the next page. Soil and Agriculture 365 Eastern wheat rice United Fertile States Crescent China Sahel sunower New Guinea Mesoamerica sorghum West Ethiopia Africa bananas Amazonia coee corn squash Andes potato Origins of agriculture Independent origin Possible independent origin Data from syntheses in Diamond, J. 1997. Guns, germs, and steel. New York: W.W. Norton; and Goudie, A. 2000. The human impact, 5th ed. Cambridge, MA: MIT Press. FIGURE 13 Beginnings of Agriculture Agriculture agriculture independently are colored green. In areas colored originated independently in multiple locations as different blue, it is not known whether people invented agriculture cultures selectively bred plants and animals from wild independently or adopted it from other cultures. The map also species. Areas where people are thought to have invented shows a few of the crops farmed in each region. Selective Breeding and Settlement Eventually, people realized they could control what they grew. Our ancestors then began planting Map it seeds only from those plants whose fruit they liked the most. These were Origins of Agriculture the beginnings of artificial selection, or selective breeding. Selective breed- The earliest widely accepted ing has resulted in all the food crops and livestock that feed you every day. evidence of agriculture is from Once our ancestors learned to cultivate crops, they began to build the Fertile Crescent region of the more permanent settlements, often near water sources. The need to Middle East. Refer to Figure 13 harvest their crops kept them settled, and once they were settled, it made as you answer the questions that sense to plant more crops. They also began to raise animals as livestock. follow. Increased populations resulted from settlement and more-reliable food 1. Interpret Maps According to supply and reinforced the need for both. Eventually, the ability to grow the map, in what four areas did excess food enabled some people to live away from the farm, leading to agriculture most likely arise the development of professional specialties, commerce, technology, cities, independently? social classes, and political organization. Agriculture ultimately brought us the civilization we know today. 2. Interpret Maps In which part of the world were coffee crops Traditional Agriculture Until the Industrial Revolution of the first planted? 1800s, the work of cultivating, harvesting, storing, and distributing crops 3. Infer Two large rivers, the everywhere was performed by human and animal muscle power, along Tigris and Euphrates, run with hand tools and non-motorized machines such as plows. This biologi- through the Fertile Crescent. cally powered agriculture is known as traditional agriculture. Traditional How did those rivers help make agriculture may use teams of worker animals and use irrigation and it a good place for agriculture? organic fertilizer, but it does not require fossil fuels. 366 Lesson 3 Industrial Agriculture Industrial agriculture and the green revolution have saved mil- lions of people from starvation. The Industrial Revolution introduced large-scale mechanization and fossil-fuel engines to agriculture just as it did to industry. Farmers could replace their horses and oxen with faster, more powerful, and more effi- cient means of harvesting, processing, and transporting crops. In addition to the efficient farm machinery that resulted from the Industrial Revolution, other changes to agriculture came in the mid- 1900s. Many of these were reactions to the Dust Bowl of the 1930s and/or based on wartime technology. There were irrigation improvements and the introduction of synthetic fertilizers. There was also the introduc- tion of chemical pesticides, which reduced competition from weeds and the loss of crops to pests. Because the soil was more productive, and fewer crops were lost to pests, yield increased. Yield is the amount of a crop produced in a given area. The Rise of Industrial Agriculture Mechanized farming technol- ogy, the fossil fuels it runs on, manufactured chemicals, and irrigation all allow for industrial agriculture. Industrial agriculture produces huge amounts of crops and livestock. It is also known as high-input agriculture because it relies on people to “put in” enormous quantities of energy, water, and chemicals. Today, industrial agriculture is practiced on more than 25 percent of the world’s croplands and on most of the croplands in the United States. Because it uses large machinery and chemicals that are customized for a specific crop, to be most efficient, industrial agriculture requires that large areas be planted with a single crop, in a monoculture. You can see a ANSWERS monoculture in Figure 14. The planting of crops in monocultures makes Map It planting and harvesting more efficient and can thereby increase harvests. 1. Mesoamerica, the Andes, the Fer- However, monocultures have drawbacks as well. Large monocultures tile Crescent, China reduce biodiversity over large areas, because far fewer wild organisms 2. Ethiopia are able to live in monocultures than in their native habitats or in more- 3. They supply water. diverse plantings. Moreover, because all the plants in a monoculture are Reading Checkpoint Sample genetically similar, they are vulnerable to the same diseases and pests. For answer: Advantage: efficiency; this reason, monocultures carry the risk of catastrophic crop failure. disadvantage: possible catastrophic crop failure because all the plants are Reading Describe one advantage and one disadvantage of a vulnerable to the same diseases and Checkpoint monoculture. pests FIGURE 14 Monoculture Most crop production in developed nations comes from monocultures such as this cornfield in Texas. Planting crops in large, uniform fields greatly improves the efficiency of planting and harvesting. Unfortunately, it also decreases biodiversity and makes crops susceptible to pests that have adapted to feed on that crop. The Green Revolution In the mid- to late 1900s, the desire for more and better food for the world’s growing population led to the green revolution, in which agricultural scientists from developed nations introduced new technology, crop varieties, and farming practices to the developing world. (Green in this context implies “covered with plants” rather than “environmen- tally friendly.”) ▶ Technology The technology sharing began in the 1940s, when U.S. scientist Norman Borlaug introduced Mexico’s farmers to a specially bred strain of wheat (Figure 15). It produced large seed heads, was short enough to avoid wind damage, resisted diseases, and produced high yields. Within two decades Mexico