Numbers show that the prediction of Thomas Malthus should be treated with more respect. Even without saying it, he inspired the worldwide initiative for scientific studies and search for discoveries to improve crop farming methods.
In the 18th century, he published his famous treatise Essay on the Principles of Population. This paper survived and has become the basis of the Malthusian Theory.
An English clergyman, economist and demographer, Thomas Malthus had come to the conclusion that the rate of growth of the world’s population was outstripping the capacity of the land to provide the food necessary to subsistence and that only recurring famine, pestilence, or wars would tend to keep down the number of inhabitants (Rook, A. (ed.). 1958. The Origins and Growth of Biology. Harmondsworth, Middlesex: Penguin Books, Ltd. p. 268).
Total land area of the Earth (including inland water and Antarctica) is 57,900,000 square miles (150,100,000 square kilometers). (Source: Rand McNally World Atlas, 1993 revised ed.).
Projected total population of the Earth in 2011 is 7,000,000,000 (Source: Wikipedia, 2010. Retrieved August 22, 2010 from http://en.wikipedia.org/wiki/World_population).
Data on Early Man to Land Ratio in Relation to Subsistence: Is the Malthusian Theory Apparent?
No, Thomas Malthus must be wrong.
In North America, about 150,000 Plains Indians were able to subsist in a game-rich area of perhaps 600,000 square miles, living as nomads, gathering roots and berries, rarely growing small crops. In recent time in South America, native Indians require a hunting area of well over 10 square miles per human, probably equivalent to what primitive man required. (Went, F.W. and The Editors of Life. 1963. The Plants. NY: Time Incorporated. p. 160).
According to Allen (1975), 1600 Bushmen lived in the harsh Kalahari Desert of Botswana, Southern Africa by hunting game and gathering wild plants. A third of their protein intake came from meat, while the rest were from the mongongo or mangetti nut which also has a very high content of other important nutrients and calories. Surprisingly, each person’s daily protein intake of 93.1 grams was then exceeded only by 10 countries. (Allen, R. 1975. Natural Man. Madrid: The Danbury Press. p. 16).
The Kalahari Desert covers up to 70 percent of Botswana which has a land area of 600,370 sq. km (231,804 sq. mile) (New World Encyclopedia. 2010. Botswana. Retrieved August 22, 2010 from http://www.newworldencyclopedia.org/entry/Botswana).
Therefore, the 1,600 Bushmen lived in an area of about 420,259 sq. km (70 percent of 600,370 sq. km). Unfortunately, we have no data on the expanse of their hunting ground.
Mathematical Derivation of the Land Requirement for Subsistence by Natural Way:
Using the conversion equivalents 1 sq. mile = 2.59 sq. km = 259 ha and 1 sq. km = 100 ha, the following figures are derived:
Of the North American Plains Indians, 600,000 sq. miles for 150,000 humans is equivalent to 155,400,000 ha per 150,000 or 1,036 ha per human. This land requirement per human is so much more smaller than in South America (over 10 sq. miles or 2,590 ha per human) and that of the Bushmen in Botswana (26,266 ha per human).
Consequence of Abandoning Crop Farming and Livestock Production:
Applying this land to man ratio of 1,036 ha: 1 human to the Earth’s total land area of 150,100,000 sq. km or 15,010,000,000 ha, it would appear that the entire world will only be capable of supporting 14,488,417 lives.
This will mean that if we should abandon agriculture and revert to the primitive way of finding food from the wild (assuming that modernization is stopped), only 0.2 percent or so of the estimated 7 billion population in 2011 (2 in every 1000) will survive. Even with the food that can be had from sea water sources, the difference would still be nil.
Thomas Malthus will then be proven correct.
Of course, the premise of entirely going the natural way is unlikely.
Nonetheless, the figures presented indicate the ill effects of a bloated population; and that everyone should be more vigilant, efficient and ingenuous in the production of surplus food.
Thomas Malthus and his Malthusian Theory should always be in mind.
Suggested further reading on the development of crop farming and agriculture: