Human overpopulation (orhumanpopulation overshoot) is the idea that humanpopulations may become too large to besustained by their environment or resources in the long term. The topic is usually discussed in the context ofworld population, though it may concern individual nations, regions, and cities.
Since 1804, the global living human population hasincreased from 1 billion to 8 billion due tomedical advancements and improvedagricultural productivity. Annual world population growth peaked at 2.1% in 1968 and has since dropped to 1.1%.[1] According to the most recentUnited Nations' projections, the global human population is expected to reach 9.7 billion in 2050 and would peak at around 10.4 billion people in the 2080s, before decreasing, noting thatfertility rates are falling worldwide.[2]: 14–30 Other models agree that the population will stabilize before or after 2100.[3][4][5] Conversely, some researchers analyzingnational birth registries data from 2022 and 2023—which cover half the world's population—argue that the 2022 UN projections overestimated fertility rates by 10 to 20% and were already outdated by 2024. They suggest that the global fertility rate may have already fallen below thesub-replacement fertility level for the first time in human history and that the global population will peak at approximately 9.5 billion by 2061.[6] The 2024 UN projections report estimated that world population would peak at 10.29 billion in 2084 and decline to 10.18 billion by 2100, which was 6% lower than the UN had estimated in 2014.[7][8][9]
Early discussions ofoverpopulation in English were spurred by the work ofThomas Malthus. Discussions ofoverpopulation follow a similar line of inquiry asMalthusianism and itsMalthusian catastrophe,[10][11] a hypothetical event where population exceeds agricultural capacity, causingfamine orwar over resources, resulting inpoverty andenvironmental collapses. More recent discussion of overpopulation was popularized byPaul Ehrlich in his 1968 bookThe Population Bomb and subsequent writings.[12][13] Ehrlich described overpopulation as a function ofoverconsumption,[14] arguing that overpopulation should be defined by a population being unable to sustain itself without depletingnon-renewable resources.[15][16][17]
The belief that global population levels will become too large to sustain is a point of contentious debate. Those who believe global human overpopulation to be a valid concern, argue that increased levels ofresource consumption and pollution exceed the environment'scarrying capacity, leading to populationovershoot.[18] The population overshoot hypothesis is often discussed in relation to other population concerns such aspopulation momentum,biodiversity loss,[19][20]hunger and malnutrition,[21]resource depletion, and the overallhuman impact on the environment.[22]
Critics of the belief note that human population growth is decreasing and the population will likely peak, and possibly even begin to decrease, before the end of the century.[2]: 27 They argue the concerns surrounding population growth are overstated, noting that quickly declining birth rates and technological innovation make it possible to sustain projected population sizes. Other critics claim that overpopulation concerns ignore more pressing issues, like poverty oroverconsumption, are motivated by racism, or place an undue burden on theGlobal South, where most population growth happens.[23][24]
Modern proponents of the concept have suggested that overpopulation, population growth and overconsumption are interdependent[25][26][27] and collectively are the primary drivers of human-caused environmental problems such asclimate change[28][29] andbiodiversity loss.[30][31][32] Many scientists have expressed concern about population growth, and argue that creating sustainable societies will require decreasing the current global population.[33][34][18][35] Advocates have suggested implementation ofpopulation planning strategies to reach a proposedsustainable population.
Overpopulation hypotheses are controversial, with manydemographers and environmentalists disputing the core premise that the world cannot sustain the current trajectory of human population.[39] Additionally, manyeconomists and historians have noted that sustainedshortages andfamines have historically been caused by war,price controls, political instability, and repressive political regimes (often employingcentral planning) rather than overpopulation.[50] They also note that population growth hashistorically led to greatertechnological development andthe advancement of scientific knowledge. This has enabled theengineering ofsubstitute goods and technology that better conserve and more efficiently use natural resources, increase agricultural output with less land and water, and address human impacts on the environment. These advancements result from increasing numbers of scientists, engineers, and inventorsacross generations, alongsideincreasing and continuous revision of scientific thinking.[61] Instead,social scientists argue that disputes between themselves and biologists about human overpopulation are over theappropriateness of definitions being used (and often devolve into social scientists and biologists simplytalking past each other).[63]
Annual world population growth peaked at 2.1% in 1968, has since dropped to 1.1%, and could drop even further to 0.1% by 2100.[1] Based on this, theUnited Nations projects the world population, which is 7.8 billion as of 2020[update], to level out around 2100 at 10.9 billion[64][65][66] with other models proposing similar stabilization before or after 2100.[3][4][5] Some experts believe that a combination of factors (including technological and social change) would allow global resources to meet this increased demand, avoiding global overpopulation.[67][68] Additionally, some critics dismiss the idea of human overpopulation as ascience myth connected to attempts to blame environmental issues on overpopulation, oversimplify complex social or economic systems, or place blame on developing countries and poor populations—reinscribing colonial or racist assumptions and leading to discriminatory policy.[62][11][69][36] These critics often suggestoverconsumption should be treated as an issue separate frompopulation growth.[70][71]
World population has been rising continuously since the end of theBlack Death, around the year 1350.[73] The fastest doubling of the world population happened between 1950 and 1986: a doubling from 2.5 to 5 billion people in 37 years,[74] mainly due tomedical advancements and increases inagricultural productivity.[75][76] Due to its impact on the human ability to grow food, theHaber process enabled the global population to increase from 1.6 billion in 1900 to 7.7 billion by November 2018 and, according to theUnited Nations, eight billion as of November 2022.[77][78] Some researchers have analyzed this growth in population like other animal populations, human populations predictably grow and shrink according to their available food supply as per theLotka–Volterra equations, includingagronomist and insect ecologistDavid Pimentel,[79] behavioral scientist Russell Hopfenberg,[80][81] and anthropologistVirginia Abernethy.[82]
| Year | 1806 | 1850 | 1900 | 1940 | 1950 | 1960 | 1970 | 1980 | 1990 | 2000 | 2010 | 2020 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Billions | 1.01 | 1.28 | 1.65 | 2.33 | 2.53 | 3.03 | 3.68 | 4.43 | 5.28 | 6.11 | 6.92 | 7.76 |
World population has experienced several periods of growth since the dawn ofcivilization in theHolocene period, around 10,000 BCE. The rise of civilization roughly coincided with the retreat ofglacial ice following the end of theLast Glacial Period.[86] The advent of farming enabled population growth in many regions of the world, including Europe, the Americas, and China, continuing through the 1600s, though occasionally interrupted by plagues or other crises.[87][88] For example, the Black Death is thought to have reduced the world's population, then at an estimated 450 million in 1350, to between 350 and 375 million by 1400.[89]
After the start of theIndustrial Revolution, during the 18th century, the rate of population growth began to increase. By the end of the century, the world's population was estimated at just under 1 billion.[90] At the turn of the 20th century, the world's population was roughly 1.6 billion.[90] By 1940, this figure had increased to 2.3 billion.[91] Even more dramatic growth beginning in 1950 (above 1.8% per year) coincided with greatly increased food production as a result of the industrialization of agriculture brought about by theGreen Revolution.[92] The rate of human population growth peaked in 1964, at about 2.1% per year.[93] Recent additions of a billion humans happened very quickly: 33 years to reach three billion in 1960, 14 years for four billion in 1974, 13 years for five billion in 1987, 12 years for six billion in 1999, 11 years for seven billion in 2010, and 12 years for 8 billion toward the end of 2022.[94][95]
Population projections are attempts to show how thehuman population might change in the future.[97] These projections help toforecast the population's impact on this planet and humanity's future well-being.[98] Models of population growth take trends inhuman development, and apply projections into the future[99] to understand how they will affectfertility andmortality, and thuspopulation growth.[99]
The most recent report from theUnited Nations Population Division issued in 2022 (see chart) projects that global population will peak around the year 2086 at about 10.4 billion, and then start a slow decline (the median line on the chart). As with earlier projections, this version assumes that the global averagefertility rate will continue to fall, but even further from 2.5 births per woman during the 2015–2020 period to 1.8 by the year 2100.[100]
However, other estimates predict additional downward pressure on fertility (such as more education and family planning) which could result in peak population during the 2060–2070 period rather than later.[3][4]
According to the UN, of the predicted growth in world population between 2020 and 2050, all of that change will come fromless developed countries, and more than half will come from just 8 African countries.[100] It is predicted that the population of sub-Saharan Africa will double by 2050.[101] The Pew Research Center predicts that 50% of births in the year 2100 will be in Africa.[102] As an example of uneven prospects, the UN projects thatNigeria will gain about 340 million people, about the present population of the US, to become the 3rd most populous country, andChina will lose almost half of its population.[100]
Some scholars have argued that a form of "cultural selection" may be occurring due to significant differences in fertility rates between cultures, and it can therefore be expected that fertility rates and rates of population growth may rise again in the future.[103][104][105] An example is certain religious groups that have a higher birth rate that is not accounted for by differences in income. In his bookShall the Religious Inherit the Earth?,Eric Kaufmann argues that demographic trends point to religious fundamentalists greatly increasing as a share of the population over the next century.[106][107] From the perspective ofevolutionary psychology, it is expected that selection pressure should occur for whatever psychological or cultural traits maximize fertility.[108][109][110]
Concerns about population size or density have a long history:Tertullian, a resident of the city ofCarthage in the second centuryCE, criticized population at the time: "Our numbers are burdensome to the world, which can hardly support us... In very deed, pestilence, and famine, and wars, and earthquakes have to be regarded as a remedy for nations, as the means of pruning the luxuriance of the human race."[111] Despite those concerns, scholars have not found historicsocieties that have collapsed because of overpopulation or overconsumption.[112]
By the early 19th century, intellectuals such asThomas Malthus predicted that humankind would outgrow its available resources because a finite amount of land would be incapable of supporting a population with limitless potential for increase.[113] During the 19th century, Malthus' work, particularlyAn Essay on the Principle of Population, was often interpreted in a way that blamed the poor alone for their condition and helping them was said to worsen conditions in the long run.[114] This resulted, for example, in theEnglish poor laws of 1834[114] and a hesitating response to theIrish Great Famine of 1845–52.[115]
The firstWorld Population Conference was held in 1927 in Geneva, organized by theLeague of Nations andMargaret Sanger.[116][117][118]
Paul R. Ehrlich's bookThe Population Bomb became a bestseller upon its release in 1968 and created renewed interest in overpopulation. The book predicted population growth would lead tofamine,societal collapse, and other social, environmental and economic strife in the coming decades, and advocated for policies to curb it.[15][36][119] TheClub of Rome published the influential reportThe Limits to Growth in 1972, which used computer modeling to similarly argue that continued population growth trends would lead to global system collapse.[120] The idea of overpopulation was also a topic of some works of English-languagescience fiction anddystopian fiction during the latter part of the 1960s.[119] TheUnited Nations held the first of threeWorld Population Conferences in 1974.[121]Human population andfamily planning policies were adopted by some nations in the late 20th century in an effort to curb population growth, including inChina andIndia.[3]Albert Allen Bartlett gave more than 1,742 lectures on the threat of exponential population growth starting in 1969.[62]
However, many predictions of overpopulation during the 20th century did not materialize.[119][36] InThe Population Bomb, Ehrlich stated, "In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now,"[122] with later editions changing to "in the 1980s".[10] Despite admitting some of his earlier predictions did not come to pass, Ehrlich continues to advocate that overpopulation is a major issue.[119]
As theprofile ofenvironmental issues facing humanity increased during the end of the 20th and the early 21st centuries, some have looked to population growth as a root cause. In the 2000s,E. O. Wilson and Ron Nielsen discussed overpopulation as a threat to the quality of human life.[123][124]: 37–39 [non-primary source needed] In 2011,Pentti Linkola argued that human overpopulation represents a threat to Earth'sbiosphere.[125][non-primary source needed] A 2015 survey fromPew Research Center reports that 82% of scientists associated with theAmerican Association for the Advancement of Science were concerned about population growth.[126] In 2017, more than one-third of50 Nobel prize-winning scientists surveyed by theTimes Higher Education at theLindau Nobel Laureate Meetings said that human overpopulation andenvironmental degradation are the two greatest threats facing mankind.[127] In November that same year, theWorld Scientists' Warning to Humanity: A Second Notice, signed by 15,364 scientists from 184 countries, indicated that rapid human population growth is "a primary driver behind many ecological and even societal threats."[33] Ehlrich and other scientists at a conference in the Vatican oncontemporary species extinction linked the issue to population growth in 2017, and advocated forhuman population control, which attracted controversy from theCatholic church.[128] In 2019, a warning onclimate change signed by 11,000 scientists from 153 nations said that human population growth adds 80 million humans annually, and "the world population must be stabilized—and, ideally, gradually reduced—within a framework that ensures social integrity" to reduce the impact of "population growth on GHG emissions and biodiversity loss."[34][129]
In 2020, a quote fromDavid Attenborough about how humans have "overrun the planet" was shared widely online and became his most popular comment on the internet.[130]
TheWorld Wide Fund for Nature[131][132] (WWF) andGlobal Footprint Network have argued that the annualbiocapacity of Earth has exceeded, as measured using theecological footprint. In 2006, WWF'sLiving Planet Report stated that in order for all humans to live with the current consumption patterns of Europeans, we would be spending three times more than what the planet can renew.[133] According to these calculations, humanity as a whole was using by 2006 40% more than what Earth can regenerate.[134] Another study by the WWF in 2014 found that it would take the equivalent of 1.5 Earths of bio-capacity to meet humanity's current levels of consumption.[135] However,Roger Martin ofPopulation Matters states the view: "the poor want to get rich, and I want them to get rich," with a later addition, "of course we have to change consumption habits,... but we've also got to stabilize our numbers".[136] By 2023, the Global Footprint Network estimated that humanity's ecological footprint had increased to 1.71 Earths, indicating that human demand for ecological resources and services exceeded what Earth can regenerate in that year by 71%.[137] This level of overconsumption underscores the significant environmental pressures associated with population growth and resource use. Additionally,Earth Overshoot Day in 2023 fell on August 2, marking the date when humanity's resource consumption for the year surpassed Earth's capacity to regenerate those resources.[138]
Critics have questioned the simplifications and statistical methods used in calculating ecological footprints. Therefore,Global Footprint Network and its partner organizations have engaged with national governments and international agencies to test the results—reviews have been produced by France, Germany, the European Commission, Switzerland, Luxembourg, Japan and theUnited Arab Emirates.[139] Some point out that a more refined method of assessing Ecological Footprint is to designatesustainable versus non-sustainable categories of consumption.[140][141]
Attempts have been made to estimate the world'scarrying capacity for humans; the maximum population the world can host.[142] A 2004 meta-analysis of 69 such studies from 1694 until 2001 found the average predicted maximum number of people the Earth would ever have was 7.7 billion people, with lower and upper meta-bounds at 0.65 and 98 billion people, respectively. They conclude: "recent predictions of stabilized world population levels for 2050 exceed several of our meta-estimates of a world population limit".[143]
A 2012 United Nations report summarized 65 different estimated maximumsustainable population sizes and the most common estimate was 8 billion.[144] Advocates of reduced population often put forward much lower numbers.Paul R. Ehrlich stated in 2018 that the optimum population is between 1.5 and 2 billion.[145] In 2022 Ehrlich and other contributors to the "Scientists' warning on population", including Eileen Crist,William J. Ripple,William E. Rees and Christopher Wolf, stated that environmental analysts put the sustainable level of human population at between 2 and 4 billion people.[18] Geographer Chris Tucker estimates that 3 billion is a sustainable number.[146]
Although proponents of human overpopulation have expressed concern that growing population will lead to an increase in globalpoverty andinfant mortality, both indicators have declined over the last 200 years of population growth.[67][147]
A number of scientists have argued thathuman impacts on the environment and accompanying increase inresource consumption threatens the world'secosystems and the survival of human civilization.[148][149][150][151][152] TheInterAcademy Panel Statement on Population Growth, which was ratified by 58 membernational academies in 1994, states that "unprecedented" population growth aggravates many environmental problems, including rising levels ofatmospheric carbon dioxide,global warming, and pollution.[153] Indeed, some analysts claim that overpopulation's most serious impact is its effect on the environment.[154] Some scientists suggest that the overallhuman impact on the environment during theGreat Acceleration, particularly due to human population size and growth,economic growth, overconsumption,pollution, and proliferation of technology, has pushed the planet into a new geologicalepoch known as theAnthropocene.[155][156]
Some studies and commentary link population growth withclimate change.[164] Critics have stated that population growth alone may have less influence on climate change than other factors, such asgreenhouse gas emissions per capita.[165][120] The global consumption ofmeat is projected to rise by as much as 76% by 2050 as the global population increases, with this projected to have furtherenvironmental impacts such asbiodiversity loss and increasedgreenhouse gas emissions.[166][167][168] A July 2017 study published inEnvironmental Research Letters argued that the most significant way individuals could mitigate their owncarbon footprint is to have fewer children, followed by living without a vehicle, forgoing air travel, and adopting aplant-based diet.[169] However, even in countries that have both large population growth and major ecological problems, it is not necessarily true that curbing the population growth will make a major contribution towards resolving all environmental problems that can be solved simply with anenvironmentalist policy approach.[170]
Continuedpopulation growth and overconsumption, particularly by the wealthy, have been posited as key drivers ofbiodiversity loss andcontemporary species extinction,[171][172][151][26] with some researchers and environmentalists specifically suggesting this indicates a human overpopulation scenario.[12][173][30] TheGlobal Assessment Report on Biodiversity and Ecosystem Services, released byIPBES in 2019, states that human population growth is a factor in biodiversity loss.[174][175] IGI Global has uncovered the growth of the human population caused encroachment in wild habitats which have led to their destruction, "posing a potential threat to biodiversity components".[176]
Some scientists and environmentalists, includingJared Diamond,[177]E. O. Wilson,Jane Goodall[178] andDavid Attenborough,[179] contend that population growth is devastating tobiodiversity. Wilson for example, has expressed concern whenHomo sapiens reached a population of six billion theirbiomass exceeded that of any other large land dwelling animal species that had ever existed by over 100 times.[173]Inger Andersen, the executive director of theUnited Nations Environment Programme, stated in December 2022 as the human population reached a milestone of 8 billion and as delegates were meeting for the2022 United Nations Biodiversity Conference, that "we need to understand that the more people there are, the more we put the Earth under heavy pressure. As far as biodiversity is concerned, we are at war with [the rest of] nature."[180]
Human overpopulation and continued population growth are also considered by some, including animal rights attorney Doris Lin and philosopherSteven Best, to be ananimal rights issue, as more human activity means the destruction of animal habitats and more direct killing of animals.[181][166]: 146
Some commentary has attributeddepletion of non-renewable resources, such asland,food andwater, to overpopulation[182] and suggested it could lead to a diminished quality of human life.[124] EcologistDavid Pimentel was one such proponent, saying "with the imbalance growing between population numbers and vital life sustaining resources, humans must actively conserve cropland, freshwater, energy, and biological resources. There is a need to develop renewable energy resources. Humans everywhere must understand that rapid population growth damages the Earth's resources and diminishes human well-being."[183][184]
Althoughfood shortages have been warned as a consequence of overpopulation, according to theFood and Agriculture Organization, global food production exceeds increasing demand from global population growth.[62][185] Food insecurity in some regions is attributable to the globally unequal distribution of food supplies.[62]
The notion that space is limited has been decried by skeptics,[186] who point out that the Earth's population of roughly 6.8 billion people could comfortably be housed an area comparable in size to the state ofTexas in the United States (about 269,000 square miles or 696,706.80 square kilometres).[187] Critics and agricultural experts suggest changes to policies relating toland use oragriculture to make them more efficient would be more likely to resolve land issues andpressures on the environment than focusing on reducing population alone.[165][185]
Water scarcity, which threatens agricultural productivity, represents a global issue that some have linked to population growth.[188][189][190] Colin Butler wrote inThe Lancet in 1994 that overpopulation also has economic consequences for certain countries due to resource use.[191]
It was speculated byAldous Huxley in 1958 thatdemocracy is threatened byoverpopulation, and could give rise tototalitarian style governments.[192] Physics professorAlbert Allen Bartlett at theUniversity of Colorado Boulder warned in 2000 that overpopulation and the development of technology are the two major causes of the diminution of democracy.[193] However, over the last 200 years of population growth, the actual level of personal freedom has increased rather than declined.[147]John Harte has argued population growth is a factor in numerous social issues, includingunemployment,overcrowding,bad governance and decaying infrastructure.[151][194]Daron Acemoglu and others suggested in a 2017 paper that since the Second World War, countries with higher population growth rates experienced the most social conflict.[151][195]
Scholars such asThomas R. Malthus,Paul R. Ehrlich have argued that rapidpopulation growth can lead to societal challenges, such as worldwidefamines and massunemployment[196][197]. For example, researcherGoran Miladinov found that in low and middle-income countries, urban and rural population growth is frequently associated with undernourishment.[198] However, Ehrlich's predictions inThe Population Bomb have been criticised by academic journals. For example, a review byScience (journal) outlined that his predictions of mass famine never occurred.[199]
According to anthropologistJason Hickel, the globalcapitalist system creates pressures forpopulation growth: "more people means more labour, cheaper labour, and more consumers."[200] He and his colleagues have also demonstrated that capitalist elites throughout recent history have "usedpro-natalist state policies to prevent women from practicing family planning" in order to grow the size of their workforce.[201] Hickel has however argued that the cause of negative environmental impacts is resource extraction by wealthy countries.[202][page needed][verification needed] He concludes that "we should not ignore the relationship between population growth and ecology, but we must not treat these as operating in a social and political vacuum."[201]
A 2021 article inEthics, Medicine and Public Health argued in light of theCOVID-19 pandemic thatepidemics andpandemics were made more likely by overpopulation,globalization, urbanization and encroachment into natural habitats.[203]
They both play a significant role impacting human populations, including widespreadillness,death, andsocial disruption. While they can leave a temporary loss of population, it is followed by significant loss and suffering. These events are not the sole reason for overpopulation, but lack of access tofamily planning and reproductive contraptions,poverty andresource depletion.[204]
Several strategies have been proposed to mitigate overpopulation.
Several scientists (includingPaul Ehrlich,Gretchen Daily andTim Flannery[161][205]) proposed that humanity should work at stabilizing its absolute numbers, as a starting point towards beginning the process of reducing the total numbers. They suggested several possible approaches, including:[206][207]
There is good evidence from many parts of the world that when women and couples have the freedom to choose how many children to have, they tend to have smaller families.[211][212][213]
Some scientists, such as Corey Bradshaw and Barry Brook, suggest that, given the "inexorable demographic momentum of the global human population,"sustainability can be achieved more rapidly with a short term focus on technological and social innovations, along with reducing consumption rates, while treating population planning as a long-term goal.[214][215]
However, most scientists believe that achieving genuine sustainability is a long-term project, and that addressing population and consumption levels are both essential to achieving it.
In 1992, more than 1700 scientists from around the world signed onto a "World Scientists' Warning to Humanity," including a majority of the living Nobel prize-winners in the sciences.[216] "The earth is finite," they wrote. "Its ability to absorb wastes and destructive effluent is finite. Its ability to provide food and energy is finite. Its ability to provide for growing numbers of people is finite. And we are fast approaching many of the earth's limits."[216] The warning noted:
Pressures resulting from unrestrained population growth put demands on the natural world that can overwhelm any efforts to achieve a sustainable future. If we are to halt the destruction of our environment, we must accept limits to that growth.[216]
Two of the five areas where the signatories requested immediate action were "stabilize population" and "ensure sexual equality, and guarantee women control over their own reproductive decisions."[216]
In a follow-up message 25 years later,William Ripple and colleagues issued the "World Scientists' Warning to Humanity: A Second Notice."[217] This time more than 15,000 scientists from around the world signed on.[218] "We are jeopardizing our future by not reining in our intense but geographically and demographically uneven material consumption and by not perceiving continued rapid population growth as a primary driver behind many ecological and even societal threats," they wrote.[219] "By failing to adequately limit population growth, reassess the role of an economy rooted in growth, reduce greenhouse gases, incentivize renewable energy, protect habitat, restore ecosystems, curb pollution, halt defaunation, and constrain invasive alien species, humanity is not taking the urgent steps needed to safeguard our imperilled biosphere."[219] This second scientists' warning urged attention to both excessive consumption and continued population growth. Like its predecessor, it did not specify a definite global human carrying capacity. But its call to action included "estimating a scientifically defensible, sustainable human population size for the long term while rallying nations and leaders to support that vital goal."[220]
Subsequent scientists' calls to action have also included calls for population planning. The 2020 "World Scientists' Warning of a Climate Emergency" stated: "Economic and population growth are among the most important drivers of increases inCO2 emissions from fossil fuel combustion." "Therefore," the study noted: "we need bold and drastic transformations regarding economic and population policies."[221] "The world population must be stabilized—and, ideally, gradually reduced,"[222] it concluded, implying that humanity is overpopulated given current and expected levels of resource use and waste generation.
A follow-up scientists' warning on climate change in 2021 reiterated the need to plan and limit human numbers to achieve sustainability, proposing as a goal "stabilizing and gradually reducing the [global] population by providing voluntary family planning and supporting education and rights for all girls and young women, which has been proven to lower fertility rates."[223]
.jpg)
Education andempowerment of women and giving access tofamily planning and contraception have a demonstrated impact on reducing birthrates.[224] Many studies conclude thateducating girls reduces the number of children they have.[224] One option according to some activists is to focus on education aboutfamily planning andbirth control methods, and to make birth-control devices likecondoms,contraceptive pills andintrauterine devices easily available. Worldwide, nearly 40% ofpregnancies are unintended (some 80 million unintended pregnancies each year).[225] An estimated 350 million women in the poorest countries of the world either did not want their last child, do not want another child or want to space their pregnancies, but they lack access to information, affordable means and services to determine the size and spacing of their families[when?]. In thedeveloping world, some 514,000 women die annually of complications from pregnancy and abortion,[226] with 86% of these deaths occurring in thesub-Saharan Africa region and South Asia.[227] Additionally, 8 million infants die, many because ofmalnutrition or preventable diseases, especially from lack of access to clean drinking water.[228]
Women's rights and theirreproductive rights in particular are issues regarded to have vital importance in the debate.[120] AnthropologistJason Hickel asserts that a nation's population growth rapidly declines - even within a single generation - when policies relating to women's health and reproductive rights, children's health (to ensure parents they will survive to adulthood), and expanding education and economic opportunities for girls and women are implemented.[229]
A 2020 paper byWilliam J. Ripple and other scientists argued in favor of population policies that could advancesocial justice (such as by abolishingchild marriage, expanding family planning services and reforms that improve education for women and girls) and at the same time mitigate the impact of population growth on climate change and biodiversity loss.[162] In a 2022 warning on population published byScience of the Total Environment, Ripple, Ehrlich and other scientists appealed to families around the world to have no more than one child and also urged policy-makers to improve education for young females and provide high-quality family-planning services.[18]
An argument for space colonization is to mitigate proposed impacts of overpopulation of Earth, such asresource depletion.[230] If the resources of space were opened to use and viable life-supporting habitats were built, Earth would no longer define the limitations of growth. Although many of Earth's resources are non-renewable, off-planet colonies could satisfy the majority of the planet's resource requirements. With the availability of extraterrestrial resources, demand on terrestrial ones would decline.[231][232] Proponents of this idea includeStephen Hawking[233] andGerard K. O'Neill.[231]
Others including cosmologistCarl Sagan and science fiction writersArthur C. Clarke,[234] andIsaac Asimov,[235] have argued that shipping any excess population into space is not a viable solution to human overpopulation. According to Clarke, "the population battle must be fought or won here on Earth".[234] The problem for these authors is not the lack of resources in space (as shown in books such asMining the Sky[236]), but the physical impracticality of shipping vast numbers of people into space to "solve" overpopulation on Earth.Despite the increase in population density within cities (and the emergence of megacities),UN Habitat Data Corp. states in its reports that urbanization may be the best compromise in the face of global population growth.[237] Cities concentrate human activity within limited areas, limiting the breadth of environmental damage.[238] UN Habitat says this is only possible ifurban planning is significantly improved.[239]
Paul R. Ehrlich proposed inThe Population Bomb that rhetoric supporting the increase of city density is a means of avoiding dealing with what he views as the root problem of overpopulation and has been promoted by what he views as the same interests that have allegedly profited from population increase (such as property developers, the banking system which invests in property development, industry, and municipal councils).[240] Subsequent authors point togrowth economics as driving governments seek city growth and expansion at any cost, disregarding the impact it might have on the environment.[241]
The concept of human overpopulation, and its attribution as a cause of environmental issues, are controversial.[68][36][242][70][130]
Some critics, includingNicholas Eberstadt,Fred Pearce,Dominic Lawson and Betsy Hartmann, refer to overpopulation as a myth.[71][62][243][244][23] Predicted exponential population growth or any "population explosion" did not materialise; instead, population growth slowed.[119][37] Critics suggest that enough resources are available to support projected population growth, and thathuman impacts on the environment are not attributable to overpopulation.[178][130][244]
According to libertarian think tank theFraser Institute, both the idea of overpopulation and the alleged depletion of resources are myths; most resources are now more abundant than a few decades ago, thanks to technological progress.[245] The institute also questions the sincerity of advocates of population control in poor countries.[245][246]
Nicholas Eberstadt, apolitical economist, has criticised the idea of overpopulation, saying that "overpopulation is not really overpopulation. It is a question ofpoverty".[62]
A 2020 study inThe Lancet concluded that "continued trends in female educational attainment and access to contraception will hasten declines in fertility and slow population growth", with projections suggesting world population would peak at 9.73 billion in 2064 and fall by 2100.[247] Media commentary interpreted this as suggestingoverconsumption represents a greater environmental threat as an overpopulation scenario may never occur.[68][248]
Somehuman population planning strategies advocated by proponents of overpopulation are controversial for ethical reasons. Those concerned with overpopulation, including Paul Ehrlich, have been accused of influencing human rights abuses includingforced sterilisation policies in India and underChina's one-child policy, as well as mandatory orcoercive birth control measures taken in other countries.[3][249][37][250]
Surveys of members of theAmerican Economic Association have found that general agreement among professional economists in the United States with the statement that "The economic benefits of an expanding world population outweigh the economic costs" has grown from 36 percent in 2000,[251] to 50 percent in 2011,[252] and to 58 percent in 2021.[253]
Influential advocates such as Betsy Hartmann consider the "myth of overpopulation" to be destructive as it "prevents constructive thinking and action onreproductive rights," which acutely affects women and communities ofwomen in poverty.[243] The1994 International Conference on Population and Development (ICPD) defines reproductive rights as "the basic right of all couples and individuals to decide freely and responsibly the number, spacing, and timing of their children and to have the information to do so."[254] This oversimplification of human overpopulation leads individuals to believe there are simple solutions and the creation of population policies that limit reproductive rights.[citation needed]
In response, philosopher Tim Meijers asks the question: "To what extent is it fair to require people to refrain from procreating as part of a strategy to make the world more sustainable?"[255] Meijers rejects the idea that the right to reproduce can be unlimited, since this would not be universalizable: "in a world in which everybody had many children, extreme scarcity would arise and stable institutions could prove unsustainable. This would lead to violation of (rather uncontroversial) rights such as the right to life and to health and subsistence."[255] In the actual world today, excessive procreation could also undermine our descendants' right to have children, since people are likely to refrain (and perhaps should refrain) from bringing children into an insecure and dangerous world. Meijers, Sarah Conly, Diana Coole, and other ethicists conclude that people have a right to found a family, but not to unlimited numbers of children.[255][256][38][257]
Ehrlich advocated inThe Population Bomb that "various forms of coercion", such as removing tax benefits for having additional children, be used in cases when voluntary population planning policies fail.[119] Some nations, likeChina, have used strict orcoercive measures such as theone-child policy to reduce birth rates.[258]Compulsory or semi-compulsory sterilization, such as for token material compensation or easing of penalties,[259] has also been implemented in many countries as a form of population control.[260][3]
Another choice-based approach is financial compensation or other benefits by the state offered to people who voluntarily undergosterilization. Such policies have been introduced by the government of India.[261][249][37]
The Indian government ofNarendra Modi introducedpopulation policies in 2019, including offering incentives forsterilization by citing the risks of a "population explosion" although demographers have criticized that basis, with India thought to be undergoingdemographic transition and itsfertility rate falling. The policies have also received criticism from human and women's rights groups.[37][262]
The concept of human overpopulation has been criticized by some scholars and environmentalists as beingracist and having roots incolonialism andwhite supremacy, since control and reduction of human population is often focused on theglobal south, instead of onoverconsumption and theglobal north, where it occurs.[242][263][70][178][264]Paul Ehrlich'sPopulation Bomb begins with him describing first knowing the "feel of overpopulation" from a visit toDelhi, which some critics have accused of having racial undertones.[265]George Monbiot has said "when affluent white people wrongly transfer the blame for their environmental impacts on to the birthrate of much poorer brown and black people, their finger-pointing reinforces [Great Replacement andwhite genocide conspiracy] narratives. It is inherently racist."[24] Overpopulation is a common component ofecofascist ideology.[263][130][266]
Scholar Heather Alberro rejects the overpopulation argument, stating that the human population growth is rapidly slowing down, the underlying problem is not the number of people, but how resources are distributed and that the idea of overpopulation could fuel a racist backlash against the population of poor countries.[178]
In response, population activists argue that overpopulation is a problem in both rich and poor countries, and arguably a worse problem in rich countries, where residents' higher per capita consumption ratchets up the impacts of their excessive numbers.[213] Feminist scholar Donna Haraway notes that a commitment to enlarging the moral community to include nonhuman beings logically entails people's willingness to limit their numbers and make room for them.[267] Ecological economists like Herman Daly and Joshua Farley believe that reducing populations will make it easier to achieve steady-state economies that decrease total consumption and pollution to manageable levels.[268] Finally, as Karin Kuhlemann observes, "that a population's size is stable in no way entails sustainability. It may be sustainable, or it may be far too large."[269]
According to the writer and journalist Krithika Varagur, myths and misinformation about overpopulation ofRohingya people inMyanmar is thought to have driven theirgenocide in the 2010s.[270]
The following organizations advocate for a limit to human population growth, although their focus may be on related issues such as environmental protection:
Organization advocate against limits to human population growth.[272]
Much less frequently mentioned are, however, the ultimate drivers of those immediate causes of biotic destruction, namely, human overpopulation and continued population growth, and overconsumption, especially by the rich. These drivers, all of which trace to the fiction that perpetual growth can occur on a finite planet, are themselves increasing rapidly.
When is an area overpopulated? When its population cannot be maintained without rapidly depleting nonrenewable resources [39] (or converting renewable resources into nonrenewable ones) and without decreasing the capacity of the environment to support the population. In short, if the long-term carrying capacity of an area is clearly being degraded by its current human occupants, that area is overpopulated.
On the contrary, we devoted an entire section to the interacting and inter-dependent components of overpopulation and overconsumption, which are, for instance, also central tenets of the recent Economics of Biodiversity review (Dasgupta, 2021). Therein, the dynamic socio-ecological model shows that mutual causation drives modern socio-ecological systems. Just as it is incorrect to insist that a large global population is the sole underlying cause of biodiversity loss, so too is it naïve and incorrect to claim that high consumption alone is the cause, and so forth.
Growing human populations have significant implications for our demands on Nature, including for future patterns of global consumption.
Population growth can end and numbers can be gradually lowered within a human-rights framework. Lowering human numbers is achievable by expanding and protecting human rights, especially for children and women . . . A smaller human population will facilitate the conservation of a biodiverse planet while also supporting a higher quality of life for people by lowering pollution levels, preempting resource conflicts, ameliorating overcrowding in urban centers, and empowering girls and women
{{cite book}}:ISBN / Date incompatibility (help){{cite web}}: CS1 maint: bot: original URL status unknown (link)The power of population is so superior to the power in the earth to produce subsistence for man, that premature death must in some shape or other visit the human race
Calculations show that, maintaining the actual rate of population growth and resource consumption, in particular forest consumption, we have a few decades left before an irreversible collapse of our civilisation.
Large populations and their continued growth are also drivers of soil degradation and biodiversity loss. More people means that more synthetic compounds and dangerous throw-away plastics are manufactured, many of which add to the growing toxification of the Earth.
Twenty-nine members of the AWG supported the Anthropocene designation and voted in favour of starting the new epoch in the mid-twentieth century, when a rapidly rising human population accelerated the pace of industrial production, the use of agricultural chemicals and other human activities.
Human population has exceeded historical natural limits, with 1) the development of new energy sources, 2) technological developments in aid of productivity, education and health, and 3) an unchallenged position on top of food webs. Humans remain Earth's only species to employ technology so as to change the sources, uses, and distribution of energy forms, including the release of geologically trapped energy (i.e. coal, petroleum, uranium). In total, humans have altered nature at the planetary scale, given modern levels of human-contributed aerosols and gases, the global distribution of radionuclides, organic pollutants and mercury, and ecosystem disturbances of terrestrial and marine environments. Approximately 17,000 monitored populations of 4005 vertebrate species have suffered a 60% decline between 1970 and 2014, and ~1 million species face extinction, many within decades. Humans' extensive 'technosphere', now reaches ~30 Tt, including waste products from non-renewable resources.
By 2050 the human population will top 9 billion, and world meat consumption will likely double.
The overarching driver of species extinction is human population growth and increasing per capita consumption.
All of these are related to human population size and growth, which increases consumption (especially among the rich), and economic inequity.
Driving these threats are the growing human population, which has doubled since 1970 to 7.6 billion, and consumption. (Per capita of use of materials is up 15% over the past 5 decades.)
Human overpopulation is an animal rights issue as well as an environmental issue and a human rights issue. Human activities, including mining, transportation, pollution, agriculture, development, and logging, take habitat away from wild animals as well as kill animals directly.
And of course capitalism itself creates pressures for population growth: more people means more labour, cheaper labour, and more consumers. These pressures filter into our culture, and even into national policy: countries like France and Japan are offering incentives to get women to have more children, to keep their economies growing.
{{cite book}}: CS1 maint: location missing publisher (link){{cite journal}}: CS1 maint: multiple names: authors list (link)
| International | |
|---|---|
| National | |
| Other | |
