Fertility factor (demography)Fertility factors are determinants of the number of children that an individual is likely to have. Fertility factors are mostly positive or negative correlations without certain causations. Factors generally associated with increased fertility include the intention to have children, in advanced societies very high gender equality, religiosity, inter-generational transmission of values, marriage and cohabitation, maternal and social support, rural residence, pro family government programs, low IQ and increased food production.
Total fertility rateThe total fertility rate (TFR) of a population is the average number of children that would be born to a female over their lifetime if: they were to experience the exact current age-specific fertility rates (ASFRs) through their lifetime they were to live from birth until the end of their reproductive life. It is obtained by summing the single-year age-specific rates at a given time. , the total fertility rate varied widely across the world, from 0.78 in South Korea to 6.73 in Niger.
Population ageingPopulation ageing is an increasing median age in a population because of declining fertility rates and rising life expectancy. Most countries have rising life expectancy and an ageing population, trends that emerged first in developed countries but are now seen in virtually all developing countries. That is the case for every country in the world except the 18 countries designated as "demographic outliers" by the United Nations. The aged population is currently at its highest level in human history.
Human population planningHuman population planning is the practice of managing the growth rate of a human population. The practice, traditionally referred to as population control, had historically been implemented mainly with the goal of increasing population growth, though from the 1950s to the 1980s, concerns about overpopulation and its effects on poverty, the environment and political stability led to efforts to reduce population growth rates in many countries.
AntinatalismAntinatalism or anti-natalism is the philosophical position that assigns a negative value judgement to birth and views procreation as immoral. Antinatalists thus argue that humans should abstain from procreating. There are various reasons why antinatalists believe reproduction is immoral. The most common arguments for antinatalism include: Life entails inevitable suffering. Death is inevitable. Humans (and all forms of life) are born without their consent—no one chooses whether or not they come into existence.
Projections of population growthPopulation projections are attempts to show how the human population statistics might change in the future. These projections are an important input to forecasts of the population's impact on this planet and humanity's future well-being. Models of population growth take trends in human development and apply projections into the future. These models use trend-based-assumptions about how populations will respond to economic, social and technological forces to understand how they will affect fertility and mortality, and thus population growth.
Population momentumPopulation momentum is a consequence of the demographic transition. Population momentum explains why a population will continue to grow even if the fertility rate declines. Population momentum occurs because it is not only the number of children per woman that determine population growth, but also the number of women in reproductive age. Eventually, when the fertility rate reaches the replacement rate and the population size of women in the reproductive age bracket stabilizes, the population achieves equilibrium and population momentum comes to an end.
Political demographyPolitical demography is the study of the relationship between politics and population change. Population change is driven by classic demographic mechanisms – birth, death, age structure, and migration. However, in political demography, there is always scope for assimilation as well as boundary and identity change, which can redraw the boundaries of populations in a way that is not possible with biological populations. Typically, political-demographic projections can account for both demographic factors and transitions caused by social change.
Aging of JapanJapan has the highest proportion of elderly citizens of any country in the world. 2014 estimates showed that about 38% of the Japanese population was above the age of 60, and 25.9% was above the age of 65, a figure that increased to 29.1% by 2022. By 2050, an estimated one-third of the population in Japan is expected be 65 and older. The aging of Japanese society, characterized by sub-replacement fertility rates and high life expectancy, is expected to continue.
Human extinctionHuman extinction is the hypothetical end of the human species due to either natural causes such as population decline from sub-replacement fertility, an asteroid impact, large-scale volcanism, or via anthropogenic destruction (self-extinction). For the latter, some of the many possible contributors include climate change, global nuclear annihilation, biological warfare, and ecological collapse. Other scenarios center on emerging technologies, such as advanced artificial intelligence, biotechnology, or self-replicating nanobots.