Population control refers to the practice of artificially altering the rate of growth of a human population. Historically, this has been made possible by limiting the birth rate, usually by government mandate. It-) has been undertaken as a response to factors including high or increasing levels of poverty, environmental concerns, religious reasons, and overpopulation. The idea that population control is needed to be implemented in society dates back to 1798, when Thomas Malthus suggested it in his Essay on the Principle of Population.
In 1968, Paul Ehrlich noted in The Population Bomb that, "We must cut the cancer of population growth," and that, "if this was not done, there would be only one other solution, namely the 'death rate solution' in which we raise the death rate through war-famine-pestilence etc." In the same year, Garrett Hardin, proposed in his landmark essay The Tragedy of the Commons that society must relinquish the "freedom to breed" through "mutual coercion, mutually agreed upon." Some other stalwarts who advocated population control in the past were Bertrand Russell, John D. Rockefeller, Frederick Osborn (1952), and Isaac Asimov.
In the past, there have also been opposition to population control policies. The Roman Catholic Church has opposed abortion, sterilization, and contraception as a general practice, but specifically in regard to population control policies. Pope Benedict XVI has stated that "The extermination of millions of unborn children, in the name of the fight against poverty, actually constitutes the destruction of the poorest of all human beings".
Among the present day practices, an important example of mandated population control is China's one-child policy. China's policy of discouraging having more than one child has been credited with a very significant slowing of China's population growth, which had been very high before the policy was implemented. However, the policy has come under criticism as its implementation involved forced abortions and forced sterilization. The policy is controversial both within and outside of China because of the issues it raises, the manner in which the policy has been implemented and because of concerns about negative economic and social consequences.
In India, the government introduced Nirodh, a contraception to control child birth. It coined a slogan "Hum do, hamare do" implying one family, two children to reinforce the message of population control. Lately, a law has been framed which makes only people with two or fewer children eligible for election to a Gram panchayat, or local government. Another country that has succeeded in sharply reducing its birth rate in recent years is Iran. The government emphasizes the benefits of smaller families and the use of contraception. In fact, it is the only country where mandatory contraceptive courses are required for both males and females before a marriage license can be obtained.
Population control has been necessitated by a concept of overpopulation, a condition which does not depend only on the size or density of the population, but on the ratio of population to available sustainable resources. It also depends on the way resources are used and distributed throughout the population. Overpopulation can result from an increase in births, a decline in mortality rates due to medical advances, from an increase in immigration, or from an unsustainable biome and depletion of resources.
It is possible for very sparsely- populated areas to be overpopulated, as the area in question may have a meager or non-existent capability to sustain human life e.g. the middle of the Sahara Desert. Clean water, clean air, food, shelter, warmth and other resources necessary to sustain life need to be considered while evaluating the extent of overpopulation. Overpopulation leads to a diminished quality of life as it burdens resources such as medical care, education, proper sewage treatment and waste disposal.
The rapid increase in human population over the course of the 20th century has raised concerns about the Earth's ability to sustain a large number of inhabitants. In 2010, the world population neared roughly 7 billion with an estimated annual growth rate of 1.10 per cent. It is projected that the world population would rise to around 9 billion by the year 2050. The scientific consensus is that the current population expansion and accompanying increase in usage of resources is aggravating many environmental problems.
The rate of population growth began to increase after the start of the Industrial Revolution during the 18th century. At the turn of the 20th century, the world's population was roughly 1.6 billion. Dramatic growth of about 1.8 per cent per year beginning in 1950 coincided with greatly increased food production as a result of the industrialization of agriculture.
According to the United Nation's World Population Prospects report, the world population is currently growing by approximately 74 million people per year. It projects that almost all growth will take place in the less developed regions, where today's 5.3 billion population of underdeveloped countries is expected to increase to 7.8 billion in 2050. By contrast, the population of the more developed regions is expected to remain mostly unchanged, at 1.2 billion. By 2050, Africa will have 1.9 billion people, Asia 5.2 billion, Europe 664 million, Latin America and Caribbean 769 million and North America 448 million.
The theory of demographic transition held that, after the standard of living and life expectancy increase, family sizes and birth rates decline. Another version of demographic transition proposed by anthropologist Virginia Abernethy in her book Population Politics, states that the demographic transition occurs primarily in nations where women enjoy a special status. Abernethy claims that in strongly patriarchal nations, where women enjoy few special rights, a high standard of living tends to result in population growth.
In 1800 only 3 per cent of the world's population lived in cities, which increased to 47 per cent by the end of the 20th century. Similarly, cities with populations exceeding one million increased from 83 in 1950 to 468 by 2007. If the trend continues, the world's urban population will double every 38 years and the UN forecasts that today's urban population of 3.2 billion will rise to nearly 5 billion by 2030, when three out of five people will live in cities. The increase will be most dramatic in the poorest and least-urbanized continents of Asia and Africa.
Steps to bring the population under control are necessary as overpopulation results in inadequate fresh water for drinking water, depletion of natural resources, increased levels of air pollution, water pollution, soil contamination and noise pollution, deforestation and loss of ecosystems' changes in atmospheric composition and consequent global warming, irreversible loss of arable land and increases in desertification, Mass species extinctions, etc. It may also result in low hygiene conditions and conflict over scarce resources and crowding, leading to increased levels of warfare and may lead to less personal freedom or more restrictive laws.