Immigration to the United States has been a major source of population growth and cultural change throughout much of its history. In absolute numbers, the United States has by far the highest number of immigrants in the world, with 50,661,149 people as of 2019. This represents 19.1% of the 244 million international migrants worldwide, and 14.4% of the United States' population. In 2018, there were almost 90 million immigrants and U.S.-born children of immigrants in the United States, accounting for 28% of the overall U.S. population.
Human population planning is the practice of managing the growth rate of a human population. The practice, traditionally referred to as population control, had historically been implemented mainly with the goal of increasing population growth, though from the 1950s to the 1980s, concerns about overpopulation and its effects on poverty, the environment and political stability led to efforts to reduce population growth rates in many countries. More recently, however, several countries such as China, Japan, South Korea, Russia, Iran, Italy, Spain, Finland, Hungary and Estonia have begun efforts to boost birth rates once again, generally as a response to looming demographic crises.
Population density is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geographical term.
Overconsumption describes a situation where a consumer overuses their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this may be described as the point where the marginal cost of a consumer is greater than their marginal utility. The term overconsumption is quite controversial in use and does not necessarily have a single unifying definition. When used to refer to natural resources to the point where the environment is negatively affected, it is synonymous with the term overexploitation. However, when used in the broader economic sense, overconsumption can refer to all types of goods and services, including manmade ones, e.g. "the overconsumption of alcohol can lead to alcohol poisoning". Overconsumption is driven by several factors of the current global economy, including forces like consumerism, planned obsolescence, economic materialism, and other unsustainable business models and can be contrasted with sustainable consumption.
Family planning is the consideration of the number of children a person wishes to have, including the choice to have no children, and the age at which they wish to have them. Things that may play a role on family planning decisions include marital situation, career or work considerations, financial situations. If sexually active, family planning may involve the use of contraception and other techniques to control the timing of reproduction.
Paul Ralph Ehrlich is an American biologist known for his predictions and warnings about the consequences of population growth, including famine and resource depletion. Ehrlich is the Bing Professor Emeritus of Population Studies of the Department of Biology of Stanford University.
Zero population growth, sometimes abbreviated ZPG, is a condition of demographic balance where the number of people in a specified population neither grows nor declines; that is, the number of births plus in-migrants equals the number of deaths plus out-migrants. ZPG has been a prominent political movement since the 1960s.
Population decline, also known as depopulation, is a reduction in a human population size. Throughout history, Earth's total human population has continued to grow; however, current projections suggest that this long-term trend of steady population growth may be coming to an end.
Immigration reduction refers to a government and social policy in the United States that advocates a reduction in the amount of immigration allowed into the country. Steps advocated for reducing the numbers of immigrants include advocating stronger action to prevent illegal entry and illegal migration, and reductions in non-immigrant temporary work visas. Some advocate tightening the requirements for legal immigration requirements to reduce numbers or move the proportions of legal immigrants away from those on family reunification programs to skills-based criteria.
The Federation for American Immigration Reform (FAIR) is a nonprofit, anti-immigration organization in the United States. The group publishes position papers, organizes events, and runs campaigns in order to advocate for changes in U.S. immigration policy. The Southern Poverty Law Center classifies FAIR as a hate group with ties to white supremacist groups.
NumbersUSA is an anti-immigration advocacy group that seeks to reduce both legal and illegal immigration to the United States. It advocates for immigration reduction through user-generated fax, email, and direct mail campaigns.
Human overpopulation is the idea that human populations may become too large to be sustained by their environment or resources in the long term. The topic is usually discussed in the context of world population, though it may concern individual nations, regions, and cities.
Population Matters, formerly known as the Optimum Population Trust, is a UK-based charity that addresses population size and its effects on environmental sustainability. It considers population growth as a major contributor to environmental degradation, biodiversity loss, resource depletion and climate change. The group promotes ethical, choice-based solutions through lobbying, campaigning and awareness-raising.
World Population Day is an annual event, observed on July 11 every year, which seeks to raise awareness of global population issues. The event was established by the Governing Council of the United Nations Development Programme in 1989. It was inspired by the public interest in Five Billion Day on July 11, 1987, the approximate date on which the world's population reached five billion people. World Population Day aims to increase people's awareness on various population issues such as the importance of family planning, gender equality, poverty, maternal health and human rights.
The New Americans: Economic, Demographic, and Fiscal Effects of Immigration is a 1997 study on the demographic, economic, and fiscal consequences of immigration to the United States by the National Research Council (NRC) of the National Academy of Sciences. The NRC report found that although immigrants, especially those from Latin America, were a net cost in terms of taxes paid versus social services received, overall immigration was a net economic gain due to an increase in pay for higher-skilled workers, lower prices for goods and services produced by immigrant labor, and more efficiency and lower wages for some owners of capital. The report also notes that although immigrant workers compete with domestic workers for some low skilled jobs, some immigrants specialize in activities that otherwise would not exist in an area, and thus are performing services that otherwise would not exist, and thus can be beneficial for all domestic residents. U.S. Census Bureau's Survey of Business Owners: Hispanic-Owned Firms: 2002 indicated that the number of Hispanic-owned businesses in the United States grew to nearly 1.6 million in 2002. Those Hispanic-owned businesses generated about $222 billion in revenue. The report notes that the burden of poor immigrants is not born equally among states, and is most heavy in California.
In world demographics, the world population is the total number of humans currently alive. It was estimated by the United Nations to have exceeded eight billion in mid-November 2022. It took around 300,000 years of human prehistory and history for the human population to reach a billion and only 218 years more to reach 8 billion.
Overpopulation or overabundance is a phenomenon in which a species' population becomes larger than the carrying capacity of its environment. This may be caused by increased birth rates, lowered mortality rates, reduced predation or large scale migration, leading to an overabundant species and other animals in the ecosystem competing for food, space, and resources. The animals in an overpopulated area may then be forced to migrate to areas not typically inhabited, or die off without access to necessary resources.
In environmental science, a population "overshoots" its local carrying capacity — the capacity of the biome to feed and sustain that population — when that population has not only begun to outstrip its food supply in excess of regeneration, but actually shot past that point, setting up a potentially catastrophic crash of that feeder population once its food populations have been consumed completely. Overshoot can apply to human overpopulation as well as other animal populations: any life-form that consumes others to sustain itself.
Sustainable population refers to a proposed sustainable human population of Earth or a particular region of Earth, such as a nation or continent. Estimates vary widely, with estimates based on different figures ranging from 0.65 billion people to 9.8 billion, with 8 billion people being a typical estimate. Projections of population growth, evaluations of overconsumption and associated human pressures on the environment have led to some to advocate for what they consider a sustainable population. Proposed policy solutions vary, including sustainable development, female education, family planning and broad human population planning.
The Olduvai Theory states that the current industrial civilization would have a maximum duration of one hundred years, counted from 1930. From 2030 onwards, humankind would gradually return to levels of civilization comparable to those previously experienced, culminating in about a thousand years in a hunting-based culture, such as existed on Earth three million years ago, when the Oldowan industry developed; hence the name of this theory, put forward by Richard C. Duncan based on his experience in handling energy sources and his love of archaeology.
