In the early ages people were hunters, or predators; they had to survive by killing other species. Although predators are supposed to be the strongest in the food chain, people were vulnerable because they had to depend on the same species below them. Our senses were not developed as well either; hearing, smelling, eye sight were and still are not as good as of those below us. We can’t kill with our teeth or nails, like some alligators could. So after 4 ice ages, only 25,000 people were left. That’s when they realized that they had to change their loosing strategies and that’s when they came up with Subsistence Agriculture.
People domesticated animals, plants, and according to the number of the population today, we are doing real well. The world population grew slowly over much of the historic past; it was not until after 1900 that growth accelerated. The 1992 population was 5. 5 billion. Now the world population is increasing at about 1. 7% yr, corresponding to a doubling time of 40 years. In the early 1960s, most nations were self-sufficient in food; now only a few are. Except for parts of Africa, production exceeded population growth throughout the world. Per capita production has now slowed and appears to be declining.
In line with recent studies, we estimate that with the world population at 5. 5 billion, food production is adequate to feed 7 billion people a vegetarian diet, with ideal distribution and no grain fed to livestock. Yet possibly as many as two billion people are now living in poverty, and over 1 billion in utter poverty’ live with hunger. Inadequate distribution of food is a substantial contributing factor to this current situation. Less than one half of the world’s land area is suitable for agriculture, including grazing. Nearly all of the world’s productive land, flat and with water, is already exploited.
Most of the unexploited land is either too steep, too wet, too dry, or too cold for agriculture. Water Shortages: Pressures from growing population have strained water resources in many areas of the world. Worldwide, 214 river or lake basins, containing 40% of the world’s population, now compete for water. If we improve conservation of water, it would enhance rainfed and irrigated crop yields. A major difficulty arises simply from the rate with which food supplies would have to be expanded to pace or to exceed population growth rates in those countries experiencing high growth rates.
In order to stay even with population growth it will be necessary to expand food supplies, globally, by the rate of population increase. For many countries the rate of population expansion is in the range 2-3% per year. If the historical record is any guide, no nation with a population growth rate above 2% yr has much hope of improving its per capita supply of food unless it receives very substantial external aid and support. Of course these rates of increase for both population and food production, if achieved, cannot be sustained indefinitely.
