Britannica Book of the Year 1988 [antikvár]

World Revolution in Agriculture BY NORMAN E. BORLAUG AND CHRISTOPHER R. DOWSWELL In recent years the international news média have focused on the cruel realities of famine in drought-stricken Africa. To most citizens of the affluent nations-who have never personally known hunger-the tragic scenes of starving people and their dying animals are deplorable and incomprehensible. The situation seems especially paradoxicai when paris of the world are awash in surplus íood and farmers in many of the developed countries are struggling with the economic consequences of overproduction. Though many individuals, organizations, and governments have responded generously with emergency food aid. these are only stopgap measures. The only longterm solution is sustained agricultural development in areas where food is in short supply. Agriculture and Population. In geologic terms, the domestication of plánt and animal species is a recent event. Archaeological evidence indicates that all the major cereals, economically important legumes, root crops, and animal species that are still our principal sources of food were domesticated over a period of only 2,000-3,000 years. The process may well have begun when Neolithic women, faced with shortages when their menfolk failed to bring home enough food from hunting forays, decided that something had to be done and began searching for a means to assure a more permanent and reliable supply. It was achieved by sowing seed of the same wild grain species they had been collecting for untold millennia to supplement their meat diet. Thus, agriculture was born. With the development of agriculture somé 8,000 to 10,000 years ago, the condition of humankind began to improve markedly, and humán numbers, estimated to have been 15 millión at that time, began to increase at an accelerated rate. A more stable food supply resulted in better nutrition and the development of a settled way of life, leading to higher survival rates and yet more rapid population growth. World population presumably doubled four times from the beginning of agriculture to the start of the Christian era (to about 250 millión). It had doubled again, to 500 millión, by about 1650. The next doubling required only 200 years, producing a population of one biliion by 1850. At about that time the discovery of the nature and cause of infectious diseases-the dawn of modern medicine-began to lower death rates. It took only 80 years for the next doubling, to two biliion, which occurred Norman E. Borlaug, Dislinguished Professor of InlernaiionaI Agriculture al Texas A & M University, was awarded the Nobel Prize for Peace in 1970 for his achievemenl in laying the groundwork for the Green Revolution. Christopher R Dowswell is a consultant in agricultural communications. about 1930. Shortly thereafter, the development of sulfa drugs, antibiotics. and improved vaccines led to a further substantial reduction in death rates, especially among infants and children. The next doubling of population took only 45 years-to about 1975, when the global population reached four biliion, representing a 256-fold increase since the discovery of agriculture. While the growth of world population overall has begun to slow, the current rates in the less developed world remain frighteningly high. In 1985, with world population approaching the five biliion mark, global food production of all types stood at about 4.3 biliion metric tons, representing somé 2.2 biliion tons of edible dry matter. (See Table I.) Of this totál, 98% was produced on the land; only 1% came from the oceans and the inland waters. (A third source of food, microbial fermentation, is used primarily to produce certain vitamins and aminő acids. These products are important nutritionally, but the quantity is small, and they are not included in this survey.) Plánt products constituted 92% of the humán diet, with about 30 crop species providing most of the world's calories and protein. These included eight species of cereals, which collectively accounted for 52% of the world food supply. Animal products, constituting 7% of the world's diet, come indirectly from plants. Production, Distribution, and the Role of Science. There are two aspects to the problem of feeding the world's people. The first is the complex task of producing sufficient quantities of the desired foods to satisfy Table I. World Food Production, 1984 In 000 metric tons Edible dry% increase CommodityGrossmatter'Protein'1979-84 Cereals1,8021,50015516 Wheat5224595423 Corn (maize)4493954114 Rice, rough4703192724 Barley172151150 Sorghum/millet1039283 Roots and tubers593160108 Potato31268710 Sweet potato1173523 Cassava12947110 Legumes, oilseeds, nuts2431625510 Sugarcane and sugár beets113113011 (sugár content only)14 Vegetables and melons387475 Fruits3003925 Animal products9361807740 Milk, meat, eggs8561585937 Fish8021147 All food4,3742,20129717 'At 16ro moisture content. excludmg inedible hulis and shells Source FAO Producl/on Yearbook Formát adapted from L. T Evans (ed }. Crop Physiology (1975).