Andrey Vitalievich Korotayev is a Russian anthropologist, economic historian, comparative political scientist and sociologist, with major contributions to world-systems theory, cross-cultural studies, Near Eastern history, Big History, mathematical modelling of social and economic macrodynamics. He is the Head of the Laboratory for Monitoring of the Risks of Sociopolitical Destabilization at the National Research University Higher School of Economics, a Senior Research Professor at the Center for Big History and System Forecasting of the Institute of Oriental Studies as well as in the Institute for African Studies of the Russian Academy of Sciences. In addition, he is a Senior Research Professor of the International Laboratory on Political Demography and Social Macrodynamics of the Russian Presidential Academy of National Economy and Public Administration, as well as a Full Professor of the Faculty of Global Studies of the Moscow State University, he is co-editor of the journals Social Evolution & History and Journal of Globalization Studies, as well as History & Mathematics yearbook.
Together with Askar Akayev and George Malinetsky he is a coordinator of the Russian Academy of Sciences Program "System Analysis and Mathematical Modeling of World Dynamics". Born in Moscow, Andrey Korotayev attended Moscow State University, where he received an MA in 1984, he earned a PhD in 1993 from Manchester University, in 1998 a Doctor of Sciences degree from the Russian Academy of Sciences. Since 2000, he has been Professor and Director of the Anthropology of the East Center at the Russian State University for the Humanities and Senior Research Professor in the Oriental Institute and Institute for African Studies at the Russian Academy of Sciences. In 2001–2003, he directed the "Anthropology of the East" Program at the National Research University Higher School of Economics in Moscow and is now the Head of the Laboratory of Monitoring of the Sociopolitical Destabilization Risks at this University. In 2003–2004, he was a visiting member at the Institute for Advanced Study in Princeton, NJ.
Korotayev is a laureate of the Russian Science Support Foundation in "The Best Economists of the Russian Academy of Sciences" nomination. In 2012 he was awarded with the Gold Kondratieff Medal by the International N. D. Kondratieff Foundation. Andrey Korotayev has made important contributions to the following fields. In this field he has proposed one of the most convincing mathematical explanations for von Foerster's Doomsday Equation. In collaboration with his colleagues, Artemy Malkov and Daria Khaltourina, he has shown that till the 1970s the hyperbolic growth of the world population was accompanied by quadratic-hyperbolic growth of the world GDP, developed a number of mathematical models describing both of these phenomena simultaneously; the hyperbolic growth of the world population and quadratic-hyperbolic growth of the world GDP observed till the 1970s have been correlated by him and his colleagues to a non-linear second order positive feedback between the demographic growth and technological development that can be spelled out as follows: technological growth – increase in the carrying capacity of land for people – demographic growth – more people – more potential inventors – acceleration of technological growth – accelerating growth of the carrying capacity – the faster population growth – accelerating growth of the number of potential inventors – faster technological growth – hence, the faster growth of the Earth's carrying capacity for people, so on.
He has shown that the world urban population growth curve has up till followed a quadratic-hyperbolic pattern. In addition and his colleagues have proposed a number of forecasts of the World System development up to 2100. In collaboration with Alexander V. Markov he has demonstrated that a similar mathematical model can be developed to describe the macrotrends of biological evolution, they have shown that changes in biodiversity through the Phanerozoic correlate much better with hyperbolic model than with exponential and logistic models. The latter models imply that changes in diversity are guided by a first-order positive feedback and/or a negative feedback arising from resource limitation. Hyperbolic model implies a second-order positive feedback; the hyperbolic pattern of the world population growth has been demonstrated by Korotayev to arise from a second-order positive feedback between the population size and the rate of technological growth. According to Korotayev and Markov, the hyperbolic character of biodiversity growth can be accounted for by a feedback between the diversity and community structure complexity.
They suggest that the similarity between the curves of biodiversity and human population comes from the fact that both are derived from the interference of the hyperbolic trend with cyclical and stochastic dynamics. Korotayev has demonstrated that the hyperbolic models of this type may be used to describe in a rather accurate way the overall growth of the planetary complexity of the Earth since 4 billion BC up to the present. In the field of cliodynamics, Korotayev has developed a number of mathematical models of interaction between the long-term, "millennial" hyperbolic trend dynamics of social systems and the shorter-term, "secular", cyclical dynamics
Environmental impact of fishing
The environmental impact of fishing includes issues such as the availability of fish, overfishing and fisheries management. These issues are part of marine conservation, are addressed in fisheries science programs. There is a growing gap between the supply of fish and demand, due in part to world population growth; the journal Science published a four-year study in November 2006, which predicted that, at prevailing trends, the world would run out of wild-caught seafood in 2048. The scientists stated that the decline was a result of overfishing and other environmental factors that were reducing the population of fisheries at the same time as their ecosystems were being annihilated, yet again the analysis has met criticism as being fundamentally flawed, many fishery management officials, industry representatives and scientists challenge the findings, although the debate continues. Many countries, such as Tonga, the United States and Bahamas, international management bodies have taken steps to appropriately manage marine resources.
Reefs are being destroyed by overfishing because of the huge nets that are dragged along the ocean floor while trawling. Many corals are being destroyed and as a consequence, the ecological niche of many species is at stake; some fishing techniques cause habitat destruction. Blast fishing and cyanide fishing, which are illegal in many places, harm surrounding habitat. Blast fishing refers to the practice of using explosives to capture fish. Cyanide fishing refers to the practice of using cyanide to stun fish for collection; these two practices are used for the aquarium trade and the live fish food trade. These practices are destructive because they impact the habitat that the reef fish live on after the fish have been removed. Bottom trawling, the practice of pulling a fishing net along the sea bottom behind trawlers, removes around 5 to 25% of an area's seabed life on a single run. Most of the impacts are due to commercial fishing practices. A 2005 report of the UN Millennium Project, commissioned by UN Secretary-General Kofi Annan, recommended the elimination of bottom trawling on the high seas by 2006 to protect seamounts and other ecologically sensitive habitats.
This was not done. In mid-October 2006, United States President George W. Bush joined other world leaders calling for a moratorium on deep-sea trawling, a practice shown to have harmful effects on sea habitat and, hence, on fish populations. No further action was taken; the sea animals aquatic ecosystem may collapse due to the destruction in the food chain. Additionally, ghost fishing is a major threat due to capture fisheries. Ghost fishing occurs when a net, such as a gill net or trawl, is lost or discarded at sea and drifts within the oceans and can still act to capture marine organisms. According to the FAO Code of Conduct for Responsible Fisheries, States should act to minimize the amount of lost and abandoned gear, work to minimize ghost fishing. Overfishing has been reported due to increases in the volume of fishing hauls to feed a growing number of consumers; this has led to the breakdown of some sea ecosystems and several fishing industries whose catch has been diminished. The extinction of many species has been reported.
According to a Food and Agriculture Organization estimate, over 70% of the world’s fish species are either exploited or depleted. According to the Secretary General of the 2002 World Summit on Sustainable Development, "Overfishing cannot continue, the depletion of fisheries poses a major threat to the food supply of millions of people."The cover story of the May 15, 2003 issue of the science journal Nature – with Dr. Ransom A. Myers, an internationally prominent fisheries biologist as the lead author – was devoted to a summary of the scientific information; the story asserted that, as compared with 1950 levels, only a remnant of all large ocean-fish stocks are left in the seas. These large ocean fish are the species at the top of the food chains; this article was subsequently criticized as being fundamentally flawed, although much debate still exists and the majority of fisheries scientists now consider the results irrelevant with respect to large pelagics. The fishing down the food web is something.
Once all larger fish are caught, the fisherman will start to fish the smaller individuals, which would lead to more fish needing to be caught to keep up with demand. This decreases fish populations, as well as genetic diversity of the species, making them more susceptible to disease, less to adapt to their stressors and the environment. Additionally, catching smaller fish leads to breeding of smaller offspring, which can be problematic for fish. In many species, the smaller the female, the less fecund it is. Over-fishing can result in the over-exploitation of marine ecosystem services. Fishing can cause several negative physiological and psychological effects for fish populations including: increased stress levels and bodily injuries resulting from lodged fish hooks. Times, when this threshold is crossed, hysteresis may occur within the environment. More some ecological disturbances observed within the Black Sea marine ecosystem resulted from a combination of over-fishing and various other related human activities which adversely affected the marine environment and ecosystem.
Ecological disruption can occur due to the over-fishing of critical fish species suc
In biology or human geography, population growth is the increase in the number of individuals in a population. Many of the world's countries, including many in Sub-Saharan Africa, the Middle East, South Asia and South East Asia, have seen a sharp rise in population since the end of the Cold War; the fear is that high population numbers are putting further strain on natural resources, food supplies, fuel supplies, housing, etc. in some of the less fortunate countries. For example, the population of Chad has grown from 6,279,921 in 1993 to 10,329,208 in 2009, further straining its resources. Vietnam, Nigeria, Egypt and the DRC are witnessing a similar growth in population. Global human population growth amounts to 1.1 % per year. The global population has grown from 1 billion in 1800 to 7.616 billion in 2018. It is expected to keep growing, estimates have put the total population at 8.6 billion by mid-2030, 9.8 billion by mid-2050 and 11.2 billion by 2100. Many nations with rapid population growth have low standards of living, whereas many nations with low rates of population growth have high standards of living.
Population began growing in the Western world early in the industrial revolution of the late 18th century. The reasons for the "Modern Rise of Population" were investigated by the British health scientist Thomas McKeown. In his publications, McKeown challenged four theories about the population growth: McKeown stated that the growth in Western population surging in the 19th century, was not so much caused by an increase in fertility, but by a decline of mortality of childhood mortality followed by infant mortality, The decline of mortality could be attributed to rising standards of living, whereby McKeown put most emphasis on improved nutritional status, His most controversial idea, at least his most disputed idea, was that he questioned the effectiveness of public health measures, including sanitary reforms and quarantine, The sometime fierce disputes that his publication provoked around the "McKeown thesis", have overshadowed his more important and unchallenged argument that curative medicine measures played little role in mortality decline, not only prior to the mid-20th century but until well into the 20th century.
Although the McKeown thesis has been disputed, recent studies have confirmed the value of his ideas. His work is pivotal for present day thinking about population growth, birth control, public health and medical care. McKeown had a major influence on many population researchers, such as health economists and Nobel prize winners Robert W. Fogel and Angus Deaton; the latter considered McKeown as "the founder of social medicine". The "population growth rate" is the rate at which the number of individuals in a population increases in a given time period, expressed as a fraction of the initial population. Population growth rate refers to the change in population over a unit time period expressed as a percentage of the number of individuals in the population at the beginning of that period; this can be written as the formula, valid for a sufficiently small time interval: P o p u l a t i o n g r o w t h r a t e = P − P P A positive growth rate indicates that the population is increasing, while a negative growth rate indicates that the population is decreasing.
A growth ratio of zero indicates that there were the same number of individuals at the beginning and end of the period—a growth rate may be zero when there are significant changes in the birth rates, death rates, immigration rates, age distribution between the two times. A related measure is the net reproduction rate. In the absence of migration, a net reproduction rate of more than 1 indicates that the population of females is increasing, while a net reproduction rate less than one indicates that the population of females is decreasing. Most populations do not grow exponentially. Once the population has reached its carrying capacity, it will stabilize and the exponential curve will level off towards the carrying capacity, when a population has depleted most its natural resources; the growth of a population can be modelled by the logistic equation d P d t = r P, where P = the population after time t. As it is a separable differential equation, the population may be solved explicitly, producing a logistic function: P ( t
Off-roading is the activity of driving or riding a vehicle on unsurfaced roads or tracks, made of materials such as sand, riverbeds, snow and other natural terrain. Types of off-roading range in intensity, from leisure drives with unmodified vehicles to competitions with customized vehicles and professional drivers. Off-roaders have been met with criticism for the environmental damage caused by their vehicles. There have been extensive debates over the role of government in regulating the sport, including a Supreme Court case brought against the Bureau of Land Management. Travelling on off-road terrains require vehicles capable of accommodating off-road driving such as ATVs; these vehicles accommodate off-road conditions with extended ground clearance, off-road tires and drive-train. Some manufacturers offer vehicles meant for off-road use; some examples of recreational off-roading include the following: Dune bashing is a form of off-roading on sand dunes. A Large sport utility vehicle such as the Toyota Land Cruiser is an example of vehicle used.
Vehicles driven on dunes may be equipped with a roll cage in case of an overturn. Before entering the desert in an everyday-use SUV or pickup, it is essential to reduce the tire pressure; this is done to gain more traction by increasing the footprint of the tire and, reducing the ground pressure of the vehicle on the sand as there is a greater surface area. For example, tires with a recommended pressure of 35 psi would be reduced to 12-14 psi. A common modification is to fit beadlock rims, which allow tire pressure to be lowered further, without risking tire and rim separation. Upon entering the desert, it is common to meet with a pack of vehicles and a group leader before proceeding; the group leader leads the pack through the stunts in single file. The main reason for this technique is to prevent vehicles from losing track of direction and getting lost. High speed racing in the open desert includes chases and racing on a rough desert terrain with numerous pots and bumps at the maximum speed.
Drivers use RWD and 4WD trucks with long travel suspension, wide stance on the front and large tires which allows to maintain optimal stability at the high speed. This type of trucks is called Prerunner. Rock Racing is similar to rock crawling in the fact that the vehicles are driven over rocks, the difference is that there are no penalties for hitting cones, backing up or winching as is done in rock crawling. Rock racing involves a degree of high-speed racing not seen in typical rock crawling. Unlike stationary dune bashing that tends to revolve around a single star dune or one obstacle, cross-country off-roading is an activity that lasts several days on routes with desert or other terrains. Routes in Africa have obstacles in uninhabited and uncharted terrain; these circuit routes are over 50 km and around 300 km long This is a type of travel undertaken with a 4x4 that goes over tracks and contains some bits of off-roading. Traditionally these trips are going through uninhabited areas. Popular are the deserts in Tunisia and other North African countries, continent crossing trips through Africa, trips through Mongolia or Northern Scandinavia.
Typical modifications to vehicles for this kind of travel are the addition of extra fuel tanks, roof rack tents, elaborate storage systems in the back for food, water/drinking, spare parts and other cargo. Due to the extra weight the suspension is reinforced with stronger springs, shock absorbers etc... Green laning is a leisure pursuit suitable for any four-wheel-drive vehicle those without modifications or additional equipment; the term green lane refers to the fact that the routes are predominantly along unsurfaced tracks, forest tracks, or older roadways that may have fallen into disuse. In the UK they are roads which are not maintained in any way and will include fords. Mudding is off-roading through an area of wet clay; the goal is to drive through as far as possible without becoming stuck. There are many types of tires; some tires are mud-terrain tires and paddle tires. This activity is popular in the United States, although it is illegal on public land due to the environmental impact. Rock crawling is a category of off-roading.
Vehicles used for rock crawling are modified with different tires, suspension components that allow greater axle articulation, changes in the differential gear ratio in order to obtain characteristics suitable for low speed operation for traversing obstacles. It is common for a rock crawler to have a "spotter", an assistant on foot by the vehicle to provide information to the driver about the areas out of sight to the driver. All progress is made at low speed and the emphasis is on skill, rather than finishing first although trialing can be competitive. There are three traditional forms of off-road trailing. RTV trialing is the most common form of trialing; as the name suggests, it is for vehicles. This excludes vehicles that are modified or specially built. RTV-class vehicles can carry a wide range of suspension modifications, as well as off-road tires, recovery winches, raised air intakes etc. Vehicles on RTV trials are usually
In biology, a population is all the organisms of the same group or species, which live in a particular geographical area, have the capability of interbreeding. The area of a sexual population is the area where inter-breeding is possible between any pair within the area, where the probability of interbreeding is greater than the probability of cross-breeding with individuals from other areas. In sociology, population refers to a collection of humans. Demography is a social science. Population in simpler terms is the number of people in a city or town, country or world. In population genetics a sex population is a set of organisms in which any pair of members can breed together; this means that they can exchange gametes to produce normally-fertile offspring, such a breeding group is known therefore as a Gamo deme. This implies that all members belong to the same species. If the Gamo deme is large, all gene alleles are uniformly distributed by the gametes within it, the Gamo deme is said to be panmictic.
Under this state, allele frequencies can be converted to genotype frequencies by expanding an appropriate quadratic equation, as shown by Sir Ronald Fisher in his establishment of quantitative genetics. This occurs in Nature: localization of gamete exchange – through dispersal limitations, preferential mating, cataclysm, or other cause – may lead to small actual Gamo demes which exchange gametes reasonably uniformly within themselves but are separated from their neighboring Gamo demes. However, there may be low frequencies of exchange with these neighbors; this may be viewed as the breaking up of a large sexual population into smaller overlapping sexual populations. This failure of panmixia leads to two important changes in overall population structure: the component Gamo demos vary in their allele frequencies when compared with each other and with the theoretical panmictic original; the overall rise in homozygosity is quantified by the inbreeding coefficient. Note that all homozygotes are increased in frequency – both the deleterious and the desirable.
The mean phenotype of the Gamo demes collection is lower than that of the panmictic original –, known as inbreeding depression. It is most important to note, that some dispersion lines will be superior to the panmictic original, while some will be about the same, some will be inferior; the probabilities of each can be estimated from those binomial equations. In plant and animal breeding, procedures have been developed which deliberately utilize the effects of dispersion, it can be shown that dispersion-assisted selection leads to the greatest genetic advance, is much more powerful than selection acting without attendant dispersion. This is so for both autogamous Gamo demes. In ecology, the population of a certain species in a certain area can be estimated using the Lincoln Index. According to the United States Census Bureau the world's population was about 7.55 billion in 2019 and that the 7 billion number was surpassed on 12 March 2012. According to a separate estimate by the United Nations, Earth’s population exceeded seven billion in October 2011, a milestone that offers unprecedented challenges and opportunities to all of humanity, according to UNFPA, the United Nations Population Fund.
According to papers published by the United States Census Bureau, the world population hit 6.5 billion on 24 February 2006. The United Nations Population Fund designated 12 October 1999 as the approximate day on which world population reached 6 billion; this was about 12 years after world population reached 5 billion in 1987, 6 years after world population reached 5.5 billion in 1993. The population of countries such as Nigeria, is not known to the nearest million, so there is a considerable margin of error in such estimates. Researcher Carl Haub calculated that a total of over 100 billion people have been born in the last 2000 years. Population growth increased as the Industrial Revolution gathered pace from 1700 onwards; the last 50 years have seen a yet more rapid increase in the rate of population growth due to medical advances and substantial increases in agricultural productivity beginning in the 1960s, made by the Green Revolution. In 2017 the United Nations Population Division projected that the world's population will reach about 9.8 billion in 2050 and 11.2 billion in 2100.
In the future, the world's population is expected to peak, after which it will decline due to economic reasons, health concerns, land exhaustion and environmental hazards. According to one report, it is likely that the world's population will stop growing before the end of the 21st century. Further, there is some likelihood that population will decline before 2100. Population has declined in the last decade or two in Eastern Europe, the Baltics and in the Commonwealth of Independent States; the population pattern of less-developed regions of the world in recent years has been marked by increasing birth rates. These followed an earlier sharp reduction in death rates; this transition from high birth and death rates to low birth
In demographics, the world population is the total number of humans living, was estimated to have reached 7.6 billion people as of May 2018. It took over 200,000 years of human history for the world's population to reach 1 billion. World population has experienced continuous growth since the end of the Great Famine of 1315–1317 and the Black Death in 1350, when it was near 370 million; the highest population growth rates – global population increases above 1.8% per year – occurred between 1955 and 1975, peaking to 2.06% between 1965 and 1970. The growth rate has declined to 1.18% between 2010 and 2015 and is projected to decline further in the course of the 21st century. However, the global population is still growing and is projected to reach about 10 billion in 2050 and more than 11 billion in 2100. Total annual births were highest in the late 1980s at about 139 million, as of 2011 were expected to remain constant at a level of 135 million, while deaths numbered 56 million per year and were expected to increase to 80 million per year by 2040.
The median age of the world's population was estimated to be 30.4 years in 2018. Six of the Earth's seven continents are permanently inhabited on a large scale. Asia is the most populous continent, with its 4.54 billion inhabitants accounting for 60% of the world population. The world's two most populated countries and India, together constitute about 36% of the world's population. Africa is the second most populated continent, with around 1.28 billion people, or 16% of the world's population. Europe's 742 million people make up 10% of the world's population as of 2018, while the Latin American and Caribbean regions are home to around 651 million. Northern America consisting of the United States and Canada, has a population of around 363 million, Oceania, the least populated region, has about 41 million inhabitants. Though it is not permanently inhabited by any fixed population, Antarctica has a small, fluctuating international population based in polar science stations; this population tends to rise in the summer months and decrease in winter, as visiting researchers return to their home countries.
Estimates of world population by their nature are an aspect of modernity, possible only since the Age of Discovery. Early estimates for the population of the world date to the 17th century: William Petty in 1682 estimated world population at 320 million. More refined estimates, broken down by continents, were published in the first half of the 19th century, at 600 to 1000 million in the early 1800s and at 800 to 1000 million in the 1840s, it is difficult for estimates to be better than rough approximations, as modern population estimates are fraught with uncertainties on the order of 3% to 5%. Estimates of the population of the world at the time agriculture emerged in around 10,000 BC have ranged between 1 million and 15 million. Earlier, genetic evidence suggests humans may have gone through a population bottleneck of between 1,000 and 10,000 people about 70,000 BC, according to the Toba catastrophe theory. By contrast, it is estimated that around 50–60 million people lived in the combined eastern and western Roman Empire in the 4th century AD.
The Plague of Justinian, which first emerged during the reign of the Roman emperor Justinian, caused Europe's population to drop by around 50% between the 6th and 8th centuries AD. The population of Europe was more than 70 million in 1340; the Black Death pandemic of the 14th century may have reduced the world's population from an estimated 450 million in 1340 to between 350 and 375 million in 1400. The population of China decreased from 123 million in 1200 to 65 million in 1393 due to a combination of Mongol invasions and plague. Starting in AD 2, the Han Dynasty of ancient China kept consistent family registers in order to properly assess the poll taxes and labor service duties of each household. In that year, the population of Western Han was recorded as 57,671,400 individuals in 12,366,470 households, decreasing to 47,566,772 individuals in 9,348,227 households by AD 146, towards the End of the Han Dynasty. At the founding of the Ming Dynasty in 1368, China's population was reported to be close to 60 million.
England's population reached an estimated 5.6 million in 1650, up from an estimated 2.6 million in 1500. New crops that were brought to Asia and Europe from the Americas by Portuguese and Spanish colonists in the 16th century are believed to have contributed to population growth. Since their introduction to Africa by Portuguese traders in the 16th century and cassava have replaced traditional African crops as the most important staple food crops grown on the continent; the pre-Columbian North American population numbered somewhere between 2 million and 18 million. Encounters between European explorers and populations in the rest of the world introduced local epidemics of extraordinary virulence. According to the most extreme scholarly claims, as many as 90% of the Native American population of the New World died due to Old World diseases such as smallpox and influenza. Over the centuries, the Europeans had developed high degrees of immunity to these diseases, while the indigenous peoples had no such immunity.
During the European Agricultural and Industrial Revolutions, the life expectancy of children increased dramatically. The percentage of the children born in London who died before the age of five decreased from 74.5% in
A population decline in humans is a reduction in a human population caused by events such as long-term demographic trends, as in sub-replacement fertility, urban decay, white flight or rural flight, or due to violence, disease, or other catastrophes. Contrary to contemporary belief, depopulation can be beneficial for a region, allocating more resources and less competition for the new population, in addition to exempting the disadvantages of overpopulation, such as increased traffic, real estate prices, environmental destruction. Per-capita wealth may increase in depopulation scenarios, in addition to improvement of environmental quality-of-life indicators such as improved air and water quality, return of native species, etc; the accompanying benefits of depopulation have been termed Shrink and Prosper, with benefits being similar to the Post Civil War Gilded Age, Post World War 1 Economic Boom and the Post World War 2 Economic Boom. A reduction over time in a region's population can be caused by several factors including sub-replacement fertility, heavy emigration, disease and war.
History is replete with examples of large-scale depopulations. Many wars, for example, have been accompanied by significant depopulations. Before the 20th century, population decline was observed due to disease, starvation or emigration; the Black Death in Europe, the arrival of Old World diseases to the Americas, the tsetse fly invasion of the Waterberg Massif in South Africa, the Great Irish Famine all caused sizable population declines. In modern times, the AIDS epidemic caused declines in the population of some African countries. Less population declines are caused by genocide or mass execution. Sometimes the term underpopulation is applied to a specific economic system, it does not refer to carrying capacity, is not a term in opposition to overpopulation, which deals with the total possible population that can be sustained by available food, water and other infrastructure. "Underpopulation" is defined as a state in which a country's population has declined too much to support its current economic system.
Thus the term has nothing to do with the biological aspects of carrying capacity, but is an economic term employed to imply that the transfer payment schemes of some developed countries might fail once the population declines to a certain point. An example would be if retirees were supported through a social security system which does not invest savings, a large emigration movement occurred. In this case, the younger generation may not be able to support the older generation. Since the dire predictions of coming population overshoot in the 1960s and 70s, many other social changes, more couples in many countries have tended to choose to have fewer children. Today, sub-replacement fertility and high death rates in the former Soviet Union and its former allies are the principal reasons for that region's population decline. However, governments can influence the speed of the decline, including measures to halt, slow or suspend decline; such measures include pro-birth policies and subsidies, media influence, bolstering healthcare and laws aimed at reducing death rates.
Some of these have been applied in Russia and many Western European nations which have used immigration and other policies to suspend or slow population decline. Therefore, although the long-term trend may be for greater population decline, short term trends may slow the decline or reverse it, creating conflicting statistical data. A great example of changing trends occurring over a century is Ireland. Statistical data those comparing only two sets of figures, can be misleading and may require careful interpretation. For instance a nation's population could have been increasing, but a one-off event could have resulted in a short-term decline. Nations can acquire territory or lose territory, groups of people can acquire or lose citizenship, e.g. stateless persons, indigenous people, illegal immigrants or long-stay foreign residents. Political instability can make it difficult to conduct a census in certain regions. Further, a country's population could rise in summer and decline in winter as deaths increase in winter in cold regions.
White nationalists use evidence of a declining birth rate in support of their extremist views and calls to violence. Lower fertility rates are associated with dramatic increases in population health and longevity. Increasing populations are not necessary to maintain economic growth and social vitality because of advances in automation and workers living healthy lives much longer into old age. Declining populations pollute less. Fewer dependents mean that families and societies can achieve more productive uses of available resources and increase their quality of life. While there were in the past advantages to high fertility rates, that "demographic dividend" has now disappeared. A number of countries are declining in population, in particular Syria, Bosnia & Herzegovina, Latvia and Georgia, all with a growth rate of about minus 1.5%. Other countries with declining population are Japan, Greece, Romania and Ukraine and to a lesser degree Cuba, Spain, Estonia, Armenia, Serbia and Montenegro. Many of these countries are in Eastern Europe.
Countries approaching population declines in the 2020-25 period inclu