Human overpopulation
overpopulation oroverpopulation is a phenomenon that occurs when a high population density can cause a worsening of the environment, a decrease in the quality of life or situations of hunger and conflicts. Generally this term refers to the relationship between the human population and the environment. It can also be applied to any other species that reaches critical levels in its number of individuals.
Concept
Overpopulation comes from the overcoming by an animal species of the limits of sustainability of the biotope it inhabits. That is, a species demands more food, produces more waste and requires more space than the biotope can give or accept without sacrificing the future of other species that inhabit it. Overpopulation is as much a question of space, as of limited resources, and above all, as a direct consequence, of the extinction of the species that cohabit the overpopulated region with the human species. It is estimated that close to 99.9% of all the species that have arisen on the planet have become extinct for one reason or another, in addition to the fact that without these extinctions the human species would never have come to occupy all the terrestrial ecosystems of the planet.
Overpopulation can result from increased births, decreased mortality due to medical advances, increased immigration, or from an unsustainable biome and resource depletion. It is possible that in sparsely populated areas overpopulation occurs because the area in question cannot support that much population.
The concept of overpopulation is based on the principle that every territory has a certain carrying capacity, which is determined by the amount of resources available, and by their renewal rate. The population of any species will reach its optimal level when this is equal to the carrying capacity. If the population increases above the carrying capacity, there will be overpopulation, and therefore the resources (especially food) will not be enough for all the inhabitants of the population, producing their death by starvation.
Population and resources
Evolution of populations
The natural state of populations is equilibrium, that is, as many individuals come to reproduce in one generation as individuals did in the previous generation, and these are the ones necessary for the stable maintenance of the population. However, the balance is altered by changes in the environment (by environmental changes or by the disappearance/decrease of individuals of other species and the subsequent invasion of their former ecological niches by other species that until then occupied it), causing increases (or descendants) of the individuals that generate offspring. All growth necessarily ceases, reaching a new state of equilibrium. All species reproduce much more than is necessary to maintain their population, from fish that lay millions of eggs to elephants, which live for about 80 years and have an average of 6 individuals per breeding pair, however diseases or predators ensure that the number of reproductive individuals that in both cases leave offspring is approximately two (each species uses a reproductive strategy producing many offspring that it leaves to its own devices or few but using its time and resources in their care). In the human species, the growth towards overpopulation is due to the improvement of living conditions with a significant decrease in infant mortality that has led to the reproduction of individuals, which under other conditions would not have occurred. In most countries of the world, there has been a drastic decrease in the birth rate after the years of the baby boom or birth explosion and the Second World War; with which the birth rate that has leveled off with mortality —what is known as the replacement rate— to reach equilibrium again in many regions. However, other regions, mainly sub-Saharan Africa, where the decline in mortality is recent, are still in a phase of marked population growth (see the attached fertility map, areas with a tendency to red and purple), and its population dynamics is expected to progress towards that of other more developed countries with a birth rate similar to the replacement rate.
Overview
The human population has been increasing continuously since the end of the Black Death, around 1350, although the most significant increase has been since the 1950s, mainly due to medical advances and increased agricultural productivity. The population growth rate has decreased since the 1980s, while the absolute total number continued to increase. Recent rate increases in several countries that previously enjoyed steady declines also appear to contribute to continued growth in the total number. The United Nations has expressed concern about continued population growth in sub-Saharan Africa. Recent research has shown that those concerns are well-founded. As of November 21, 2017, the global human population is estimated at 7,583. million by the United States Census Bureau, and over 7 billion according to the United Nations. Most contemporary estimates for the Earth's carrying capacity under existing conditions lie between 4 billion and 16 billion. Depending on which estimate is used, human overpopulation may or may not have already occurred. However, the recent rapid increase in the human population is causing some concern. The population is expected to reach between 8 and 10.5 billion between the years 2040 and 2050. In 2017, the United Nations increased the medium variant projections to 9.8 billion by 2050 and 11.2 billion by 2100.
The recent rapid increase in the human population over the past three centuries has raised concerns that the planet may not be able to support present or future population numbers. The Intercademias Panel Statement on Population Growth, circa 1994, stated that many environmental problems, such as rising carbon dioxide levels in the atmosphere, global warming, and pollution, are exacerbated by expansion. of the population. Other problems associated with overpopulation include increased demand for resources such as fresh water and food, starvation and malnutrition, the consumption of natural resources (such as fossil fuels) faster than the rate of regeneration, and a deterioration of life conditions. Wealthy but heavily populated territories such as Britain are dependent on food imports from abroad. This was severely felt during the world wars when, despite food efficiency initiatives such as 'dig for victory'; and food rationing, Britain needed to fight to secure import routes. However, many believe that waste and overconsumption, especially by wealthy nations, is putting more pressure on the environment than overpopulation.
Most countries do not have a direct policy of limiting their birth rates, but rates have still declined due to education about family planning and increased access to birth control and contraception. Only China imposed legal restrictions on having more than one child. The alien solution and other technical solutions have been proposed as ways to mitigate overpopulation in the future.
Story of a concern
Concerns about overpopulation are an old issue. Tertullian was a resident of the city of Carthage in the second century AD. C., when the population of the world was approximately 190 million inhabitants (only 3-4% of what it is today). In particular, he said: "What most often meets our eye is our abundant population." Our numbers are heavy to the world, who can hardly support us... Indeed, pestilence, famine, and wars, and earthquakes must be regarded as a remedy for nations, as the means to prune the exuberance of the human race&# 3. 4;. Before that, Plato, Aristotle, and others also took up the subject.
Throughout recorded history, population growth has been slow despite high birth rates, due to war, plagues and other diseases, and high infant mortality. During the 750 years before the Industrial Revolution, the world's population increased very slowly, staying below 250 million.
By the turn of the 19th century, the world's population had grown to a billion people, and intellectuals such as Thomas Malthus predicted that humanity would outgrow its available resources, because a finite amount of land would be unable to support a population with unlimited potential. The mercantilists argued that a large population was a form of wealth that allowed larger markets and armies to be created.
During the 19th century, Malthus's work was often interpreted in a way that blamed the poor only for their condition and helping them was said to worsen conditions in the long run. This resulted, for example, in the English Poor Laws of 1834 and a faltering response to the Great Irish Famine of 1845-52.
The 2004 United Nations Population Assessment Report projects that world population will stabilize by 2050 and remain stable until 2300. A 2014 study published in Science challenges this projection, stating that population growth will continue into the next century. Adrian Raftery, a professor of statistics and sociology at the University of Washington and one of the study's collaborators, says: last 100 years was that the world population, which is currently around 7 billion, would rise to 9 billion and stabilize or probably decline. We find that there is a 70 percent chance that the world's population will not stabilize in this century. Population, which had been left off the global agenda, remains a very important issue ". The projection suggests that the population could grow to 15 billion by the year 2100.
In 2017, more than a third of the 50 Nobel Prize-winning scientists surveyed by The Times Higher Education at the Lindau Nobel Laureate Meetings said that human overpopulation and environmental degradation are the two greatest threats facing humanity. In November of that same year, a statement by 15,364 scientists from 184 countries indicated that rapid human population growth is the "main driver behind many ecological and even social threats".
World population growth projections
Projections of population growth by continents in 2050:
- Africa 1.8 billion
- Asia 5.3 billion
- Europe 628 million
- Latin America and the Caribbean 809 million
- North America 392 million
The world population is projected to continue to grow at least until 2050, with the population reaching 9 billion in 2040, and some predictions put the population at 11 billion in 2050. By 2100, the population could reach 15 billion. Walter Greiling projected in the 1950s that the world's population would peak at about 9 billion, in the next century XXI, and then would stop growing, after a Third World readjustment and a cleanup of the tropics.
In 2000, the United Nations estimated that the world's population was growing at a rate of 1.14% (or about 75 million people) per year and, according to data from the CIA World Factbook, the world's human population today increases by 145 people every minute.
According to the United Nations report on World Population Prospects:
- The global population is currently growing by approximately 74 million people per year. The current predictions of the United Nations estimate that the world ' s population will reach about 9 billion by 2050, assuming a decrease in the average fertility rate from 2.5 to 2.0.
- Almost all growth will take place in the less developed regions, where the current 5.3 billion inhabitants of the underdeveloped countries are expected to increase to 7.8 billion by 2050. On the contrary, the population of the more developed regions will remain virtually unchanged, at 1200 million. An exception is the population of the United States, which is expected to increase by 44% between 2008 and 2050.
- In 2000-2005, average global fertility was 2.65 children per woman, approximately half of the level in 1950-1955 (5 children per woman). In the medium variant, global fertility is expected to further decrease to 2.05 children per woman.
- During 2005-2050, nine countries are expected to account for half of the expected global population: India, Pakistan, Nigeria, the Democratic Republic of the Congo, Bangladesh, Uganda, the United States, Ethiopia and China, including according to the size of their contribution to population growth.
- World life expectancy at birth is expected to continue to increase from 65 years in 2000-2005 to 75 years in 2045-2050. In the more developed regions, the projection is 82 years for the year 2050. Among the least developed countries, where the current life expectancy is less than 50 years old, it is expected to increase to 66 years by 2045-2050.
- The population of 51 countries or areas is expected to be lower in 2050 than in 2005.
- During 2005-2050, the net number of international migrants to more developed regions is expected to be 98 million. As deaths are projected to exceed births in the more developed regions by 73 million during 2005-2050, the population growth in these regions is largely due to international migration.
- In 2000-2005, net migration in 28 countries prevented population decline or at least doubled the contribution of natural increase (lower deaths) to population growth.
- Birth rates are falling into a small percentage of developing countries, while the real population in many developed countries will fall without immigration.
Urban growth
In 1800, only 3% of the world's population lived in cities. For the 20th century, 47% did. In 1950 there were 83 cities with populations exceeding one million inhabitants; but by 2007, this had risen to 468 agglomerations of more than one million. If the trend continues, the world's urban population will double every 38 years, according to the researchers. The UN forecasts that the current 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, Asia and Africa. Projections indicate that most urban growth in the next 25 years will take place in developing countries. One billion people, one seventh of the world's population, or one third of the urban population, now live in slums, which are considered "breeding ground" of social problems such as unemployment, poverty, crime, drug addiction, alcoholism and other social diseases. In many poor countries, slums have high disease rates due to unsanitary conditions, malnutrition, and lack of basic health care.
In 2000, there were 18 megacities (conurbations such as Tokyo, Beijing, Guangzhou, Seoul, Karachi, Mexico City, Mumbai, São Paulo, London, and New York) with populations greater than 10 million. Greater Tokyo already has 35 million, more than the entire population of Canada (at 34.1 million).
According to the Far East Economic Review, Asia alone will have at least 10 'hypercities' by 2025, that is, cities inhabited by more than 19 million people, including Jakarta (24.9 million people), Dhaka (25 million), Karachi (26.5 million), Shanghai (27 million) and Mumbai (33 million). million). Lagos has grown from 300,000 inhabitants in 1950 to an estimated 15 million today, and the Nigerian government estimates that the city will have expanded to 25 million residents by 2015. Chinese experts forecast that Chinese cities will contain 800 million people by 2020.
Effects of human overpopulation
Humanity's overall impact on the planet is affected by many factors other than population. Lifestyle (including resource utilization) and pollution (including carbon footprint) are equally important. In 2008, The New York Times stated that people in the world's developed nations consume resources such as oil and metals at nearly 32 times the rate of those in the developing world, who make up the majority of the human population.
Some problems associated with or exacerbated by overpopulation and overconsumption by humans include:
- Inadequate fresh water for drinking, as well as poor treatment of wastewater and discharge of effluents. Some countries, such as Saudi Arabia, use costly energy desalination to solve the problem of water shortages.
- Exhaustion of natural resources, especially fossil fuels.
- Increased global energy consumption and predictions.
- Increased levels of air pollution, water pollution, soil pollution and acoustic pollution. Once a country has been industrialized and enriched, a combination of government regulation and technological innovation makes pollution decline substantially, even as the population continues to grow.
- Deforestation and loss of ecosystems that contribute valuablely to the global balance of atmospheric oxygen and carbon dioxide; nearly eight million hectares of forest are lost each year.
- Changes in atmospheric composition and consequent global warming.
- Loss of arable land and increased desertification. Deforestation and desertification can be reversed by adopting property rights, and this policy is successful even when the human population continues to grow.
- Mass extinction of species and contraction of biodiversity of a reduced habitat in tropical forests due to cutting and burning techniques sometimes practised by migrant farmers, especially in countries with rapid rural population expansion; current rates of extinction can be as high as 140,000 species lost per year. As of February 2011, the IUCN Red List lists a total of 801 species of animals that were extinguished during recorded human history, although the vast majority of exemptions are considered undocumented. Biodiversity would continue to grow at an exponential rate if it were not for human influence. Sir David King, chief scientific exassor of the UK government, said in a parliamentary investigation: "It is clear that the massive growth of the human population during the 20th century has had more impact on biodiversity than any other single factor." Paul and Anne Ehrlich said that population growth is one of the main drivers of the Earth's extinction crisis. Chris Hedgeinformed in 2009 that: "The dolphin of the Yangtze River, the grey Atlantic whale, the black rhinoceros of West Africa, the Merriam elk, the grizzly bear of California, the silver trout, the blue luke and the dark sea sparrow are all victims of human superpopulation."
- High infant and child mortality.
- Intensive industrial cultivation to support large populations. It leads to human threats, including the evolution and spread of antibiotic-resistant bacterial diseases, excessive air and water pollution and new viruses that infect humans.
- More likelihood of new epidemics and pandemics. For many environmental and social reasons, including overcrowding, malnutrition and inadequate, inaccessible or non-existent health care, the poor are more likely to be exposed to infectious diseases.
- Inanition, malnutrition or poor diet with health problems and dietary deficiency (e.g., rachitism).
- Poverty along with inflation in some regions and a low level resulting from capital formation. Poverty and inflation are compounded by poor government and poor economic policies.
- Low life expectancy in countries with fastest-growing populations.
- Antihygienic living conditions for many people based on water resource depletion, unprocessed wastewater discharge and solid waste disposal. However, this problem can be reduced with sewer adoption. For example, after Karachi installed sewers in Pakistan, its infant mortality rate was substantially reduced.
- High crime rate due to drug cartels and increased robbery by people who steal resources to survive.
- Conflict over scarce resources and overcrowding, leading to increased levels of war.
- Reduced personal freedom and more restrictive laws. Laws regulate and shape politics, economy, history and society and serve as mediators of relationships and interactions among people. The higher the population density, the more frequent these interactions become, and thus the need for more laws and/or laws more restrictive to regulate these interactions and relationships arises. Even Aldous Huxley speculated in 1958 that democracy is threatened by overpopulation and could lead to totalitarian-style governments.
David Attenborough described the level of human population on the planet as a multiplier of all other environmental problems. In 2013, he described humanity as "a plague on Earth" which must be controlled by limiting population growth.
Proposed solutions and mitigation measures
"However, given the current levels of violence by this culture against humans and the natural world, it is not possible to speak of reductions in population and consumption that do not involve violence and deprivation, not because reductions in themselves necessarily involve violence, but because violence and deprivation have become the default of our culture". Derrick Jensen. Endgame, 2006.
Various solutions and mitigation measures have the potential to reduce overpopulation. Some solutions must be applied at the global planetary level (for example, through UN resolutions), while others apply at the country or state government level, and some at the family or individual level. Some of the proposed mitigations are intended to help implement new social, cultural, behavioral, and political norms to replace or significantly modify current norms.
For example, in societies like China, the government has established policies that regulate the number of children allowed to a couple. Other societies have implemented social marketing strategies to educate the public about the effects of overpopulation. "The intervention can be widespread and performed at low cost. Produce and distribute a variety of printed materials (flyers, brochures, fact sheets, stickers) in all communities, such as local places of worship, sporting events, local food. markets, schools and car parks (taxis/bus stops) ".
Such cues work to introduce the problem so that new or changed social norms are easier to implement. Certain government policies are making it easier and more socially acceptable to use contraception and abortion. An example of a country whose laws and regulations are hampering the global effort to curb population growth is Afghanistan. "Afghan President Hamid Karzai's passage of the Shia Personal Status Law in March 2009 effectively destroyed the rights and freedoms of Shia women in Afghanistan. Under this law, women do not have the right to deny their husbands sex unless they are sick. if they do ".
Scientists and technologists such as the Huesemanns or the Ehrlichs warn that science and technology, as currently practiced, cannot solve the serious problems facing global human society and that cultural, social, and economic change is needed. policy to reorient science and technology in a more socially and environmentally responsible way in a sustainable direction.
Reduce overpopulation
Main article: Human population control
Education and empowerment
One option is to focus on education about overpopulation, family planning, and contraception, and to make contraceptive devices such as male and female condoms, birth control pills, and intrauterine devices readily available. Worldwide, almost 40% of pregnancies are unintended (some 80 million unwanted pregnancies per year). An estimated 350 million women in the world's poorest countries did not want their last child, did not want another child or wanted to space their pregnancies, but lacked access to affordable information, means and services to determine the size and spacing of pregnancies. In the United States in 2001, nearly half of all pregnancies were unintended. In the developing world, some 514,000 women die annually from complications of pregnancy and abortion, and 86% of these deaths occur in the womb. region of sub-Saharan Africa and South Asia. In addition, 8 million children die, many due to malnutrition or preventable diseases, especially lack of access to safe drinking water.
The rights of women and their reproductive rights in particular are issues that are considered to be of vital importance in the debate.
The only ray of hope I can see, and it's not much, is that wherever women control their lives, both politically and socially, where medical services allow them to grapple with control of birth rate and where their husbands allow them to make those decisions, then there the birth rate will decrease. Women don't want to have 12 children, nine of whom will die. -David Attenborough
Egypt announced a program to reduce its overpopulation through family planning education and inserting women into the workforce. It was announced in June 2008 by the Ministry of Health and Population, and the government allocated 480 million Egyptian pounds (about 90 million US dollars) for the program.
Several scientists (including, for example, Paul and Anne Ehrlich and Gretchen Daily) have proposed that humanity should work to stabilize its absolute numbers, as a starting point to begin the process of reducing the total numbers. They suggested the following solutions and policies: follow a socio-cultural and behavioral norm of small size worldwide (especially the limit of one child per family) and provide contraception to all, along with adequate education on its use and benefits (while providing access to safe and legal abortion in support of contraception), combined with a significantly more equitable distribution of resources globally.
Business magnate Ted Turner proposed a cultural norm of "one child per family voluntary, not enforced. A "promise two or fewer" is run by Population Matters (a UK organisation), where people are encouraged to limit themselves to the size of a small family.
Population planning that is intended to reduce population size or growth rate may promote or enforce one or more of the following practices, although other methods also exist:
- Greater and better access to contraception
- Reduce infant mortality so that parents do not need to have many children to ensure that at least some survive until adulthood.
- Improve the status of women to facilitate a diversion from the traditional sex division of labour.
- Policies of a child and two children and other policies that restrict or discourage births directly.
- Family planning
- Create small family role models
- Stricter immigration restrictions
The methods chosen may be strongly influenced by the cultural and religious beliefs of community members.
Birth regulations
Overpopulation can be mitigated by birth control; some nations, such as the People's Republic of China, use strict measures to reduce birth rates. Religious and ideological opposition to birth control has been cited as a contributing factor to overpopulation and poverty.
Sanjay Gandhi, son of the late Indian Prime Minister Indira Gandhi, implemented a forced sterilization program between 1975 and 1977. Officially, men with two or more children had to undergo sterilization, but there was a greater focus on sterilizing to women than to sterilize men. This program is still remembered and criticized in India, blamed for creating a public aversion to family planning, which hampered government programs for decades.
Urban designer Michael E. Arth has proposed an "marketable, options-based birth license plan" which he calls 'birth credits'. The birth credits would allow any woman to have as many children as she wants, as long as she purchases a license for any child beyond an average allowance which would result in a zero population growth. If that allowance were determined to be a child, for example, then the first child would be free, and the market would determine how much the license would cost for each additional child. The additional credits would expire after a certain time, so these credits could not be accumulated by speculators. The actual cost of the credits would be only a fraction of the actual cost of bearing and raising a child, so the credits would serve more as a wake-up call to women who may otherwise bear children without seriously considering the long-term consequences. term for themselves or society.
Another choice-based approach, similar to Arth birth credits, is financial compensation or other benefits (goods and/or free services) from the state (or state-owned companies) offered to people who voluntarily become sterilize. Such compensation has been offered in the past by the Indian government.
In 2014, the United Nations estimated that there is an 80% chance that the global population will be between 9.6 billion and 12.3 billion by the year 2100. Most of the projected global population increase will occur in Africa and the South of Asia. Africa's population is expected to increase from the current one billion to four billion by the year 2100, and Asia could add another billion in the same period.
Because the median age of Africans is relatively low (for example, in Uganda it is 15), birth credits would have to limit fertility to one child for every two women to reach country levels developed immediately. For countries with a broad base in their population pyramid, people of childbearing age will need a generation to start their families. An example of population growth is China, which added perhaps 400,000 more people after its one-child policy was enacted. Arth has suggested that the focus should be on developed countries and that a combination of birth credits and additional compensation provided by developed countries could quickly lead to zero population growth while rapidly raising the standard of living in developing countries. development.
Alien Settlement
Several scientists and science fiction authors have contemplated that overpopulation on Earth could be remedied in the future through the use of alien settlements. In the 1970s, Gerard K. O'Neill suggested building space habitats that could support 30,000 times the carrying capacity of Earth using the asteroid belt alone, and that the Solar System as a whole could sustain rates Current population growth rates over a thousand years. Marshall Savage (1992, 1994) has projected a human population of five trillion in the entire Solar System in the year 3000, with the majority of the population in the asteroid belt. Freeman Dyson (1999) favors the Kuiper belt as humanity's future home, suggesting that this could happen within a few centuries. In Mining the Sky, John S. Lewis suggests that the resources of the solar system could support 10 quadrillion people. In an interview, Stephen Hawking stated that overpopulation is a threat to human existence and that "our only chance for long-term survival is not to stare into planet Earth, but to spread out into space."
K. Eric Drexler, famous inventor of the futuristic concept of molecular nanotechnology, has suggested in Engines of Creation that colonizing space will mean breaking the Malthusian limits for the growth of the human species.
It is possible that other parts of the Solar System will be inhabited by humanity at some point in the future. Geoffrey Landis of NASA's Glenn Research Center in particular has noted that "at cloud level, Venus is a paradise planet," as one could easily build aerostat habitats and floating cities, based on the concept that breathable air is extractable from the dense atmosphere of Venus. Venus, like Saturn, Uranus, and Neptune, in the upper layers of their atmospheres, would even allow gravity nearly as strong as Earth's (see: Colonization of Venus).
Many science fiction authors, including Carl Sagan, Arthur C. Clarke, and Isaac Asimov, have argued that sending 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". The problem for these authors is not the lack of resources in space (as shown in books such as Mining the Sky), but rather the physical impracticality of sending large numbers of people into space to "solve" overpopulation on Earth. However, Gerard K. O'Neill's calculations show that Earth could offload all of the new population growth with a launch service industry roughly the same size as today's airline industry.
The StarTram concept, by James R. Powell (the co-inventor of maglev transport) and others, envisions a capacity to send up to 4 million people into space per facility per decade. A hypothetical alien colony could grow only for reproduction (ie, no immigration), with all inhabitants being direct descendants of the original settlers.
Urbanization
Despite the increase in population density within cities (and the appearance of megacities), UN Habitat states in its reports that urbanization may be the best compromise against the growth of the world population. Cities concentrate human activity within limited areas, limiting the extent of environmental damage. But this mitigating influence can only be achieved if urban planning is significantly improved and city services are adequately maintained.
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