At the same time, lifespans are increasing around the world. Those of us who are alive today will likely live much longer than most of our ancestors. Global average life expectancy has more than doubled since , thanks to advancements in medicine, technology, and general hygiene.
Falling mortality rates are certainly nothing to complain about either, but widespread longevity does contribute to the mathematics of increasing population numbers. The global fertility rate has fallen steadily over the years, down from an average of 5 children per woman in to 2.
Yet, on the whole, contraceptive use is still underutilized. For example, according to the WHO, an estimated million women in developing countries who want to avoid pregnancy are not using modern contraceptives. Getting more women the access and agency to utilize family planning methods could go a long way in flattening the population curve. Although female access to education has increased over the years, the gender gap remains.
Roughly million girls worldwide are out of school currently, and an estimated 15 million girls of primary school age will never learn to read and write, compared with 10 million boys. Increasing and encouraging education among women and girls can have a number of positive ripple effects, including delayed childbearing , healthier children, and an increase in workforce participation.
Plenty of evidence suggests a negative correlation between female education and fertility rates. If increased female education can delay or decrease fertility and provide girls with opportunities beyond an early marriage, it could also help to mitigate current population trends. More people means an increased demand for food, water, housing, energy, healthcare, transportation, and more.
Ministries of finance or planning commissions often make detailed projections for specific sectors but rarely examine alternative population trajectories. They should. Economists at the Copenhagen Consensus Center, a think tank, last year ranked family planning as one of the most cost-effective development interventions see go. Family planning must be reclassified as a development intervention as well as being a health and human-rights intervention to give it the high national and global priority it deserves.
This would lead to a more cost-effective use of scarce development resources, and to more rapid growth in living standards in poor countries. The median age of populations is rising, especially in the developed world, as a consequence of lower birth rates and rising lifespans. Europe and Japan now host the highest proportion of people aged over Further increase in this proportion is expected, putting enormous pressure on pension and health-care systems, and slowing economic growth.
The flow of people from poor and war-torn countries and continents to nearby developed ones for example, from Africa and the Middle East to Europe is rising.
The tension this creates will grow as populations in poor countries rise, and while the economic disparities between sending and receiving countries remain large. Low birth rate. In most developed countries and in a growing number of Asian and Latin American nations, women are having fewer than two children each — the level needed for long-term population stability.
This causes population ageing and decline for example, the populations of Eastern Europe and Japan will probably shrink by more than one-third by The near-absence of children to provide support will make life difficult for the elderly in countries where societal safety nets are weak such as China. Missing women. There are million fewer women than naturally expected owing to sex-selective abortion and greater female mortality throughout life for example, from female infanticide. In the past two decades, the number of such abortions has risen to about 1.
These statistics document the widespread gender discrimination that still exists in many countries. An excess of single men may lead to social unrest and trafficking in women and girls. Environmental degradation. Unprecedented global threats such as climate change and decreasing biodiversity have been building and will become more severe as populations, economies and consumption grow. Crucial local environmental problems — including shortages of fresh water and arable land, mounting waste, and air, water and soil pollution — adversely affect health and threaten the expansion of food production required to feed more people a better diet.
Economic stagnation. In poor societies, populations often double in size in two or three decades. Industries, offices, housing, schools, health clinics and infrastructure must be built at least at the same rate. Many communities are unable to keep up — as is evident from high unemployment rates, explosive growth of slum populations, overcrowded schools and health facilities and dilapidated public infrastructure such as roads, sewage systems and power grids. Furthermore, in rapidly growing regions, about half 1 of the population is aged under The low ratio of workers to dependents depresses living standards and makes it more difficult to invest in the physical and human capital needed.
The size of the formal labour force is also limited when women remain at home to care for large families. Maternal mortality. High birth rates mean frequent childbearing. Each pregnancy is associated with a risk of death or disability, and this is highest in countries with weak health-care systems.
For example, in the poorest countries of West Africa, a woman's risk of dying in childbirth before the end of her reproductive years is about 1 in Political unrest. Youth unemployment becomes widespread when economies are unable to provide jobs. Vigorous competition for few jobs leads to low wages, which in turn contribute to poverty. Large numbers of unemployed and frustrated young men, in particular, fuel socio-economic tensions, high crime rates and political instability.
Bloom, D. May, J. Singh, S. Cleland, J. Abbasi-Shavazia, M. Asian Pop. Article Google Scholar. Westoff, C. The precipitous decline in the death rate that is occurring in the low-income countries of the world is a consequence of the development and application of low-cost public health techniques. Figure 2. Schematic presentation of birth and death rates in less-developed countries, midth century.
The steep drop in the death rate from approximately 35 per thousand began at times varying roughly between and from country to country.
Instead, the less-developed areas have been able to import low-cost measures of controlling disease, measures developed for the most part in the highly industrialized countries.
The use of residual insecticides to provide effective protection against malaria at a cost of no more than 25 cents per capita per annum is an outstanding example. Other innovations include antibiotics and chemotherapy, and low-cost ways of providing safe water supplies and adequate environmental sanitation in villages that in most other ways remain relatively untouched by modernization. The death rate in Ceylon was cut in half in less than a decade, and declines approaching this in rapidity are almost commonplace.
The result of a precipitous decline in mortality while the birth rate remains essentially unchanged is, of course, a very rapid acceleration in population growth, reaching rates of three to three and one-half per cent.
This extreme rate is undoubtedly due to temporary factors and would stabilize at not more than three per cent. But even at three per cent per year, two centuries would see the population of Mexico grow to about Two centuries is a long time, however. Might we not expect that long before years had passed the population of Mexico would have responded to modernization, as did the populations of western Europe, by reducing the birth rate? A positive answer might suggest that organized educational efforts to reduce the birth rate are not necessary.
But there is a more immediate problem demanding solution in much less than two centuries: Is the current demographic situation in the less-developed countries impeding the process of modernization itself? The combination of high birth rates and low or rapidly declining death rates now found in the less-developed countries implies two different characteristics of the population that have important impli-.
One important characteristic is rapid growth, which is the immediate consequence of the large and often growing difference between birth and death rates; the other is the heavy burden of child dependency which results from a high birth rate whether death rates are high or low. A reduced death rate has only a slight effect on the proportion of children in the population, and this effect is in a rather surprising direction.
The kinds of mortality reduction that have actually occurred in the world have the effect, if fertility remains unchanged, of reducing rather than increasing the average age of the population.
Mortality reduction produces this effect because the largest increases occur in the survival of infants, and, although the reduction in mortality increases the number of old persons, it increases the number of children even more. The result is that the high fertility found in low-income countries produces a proportion of children under fifteen of 40 to 45 per cent of the total population, compared to 25 per cent or less in most of the industrialized countries.
What do these characteristics of rapid growth and very large proportions of children imply about the capacity to achieve rapid industrialization? It must be noted that it is probably technically possible in every less-developed area to increase national output at rates even more rapid than the very rapid rates of population increase we have discussed, at least for a few years. The reason at least slight increases in per capita income appear feasible is that the low-income countries can import industrial and agricultural technology as well as medical technology.
Briefly, the realistic question in the short run does not seem to be whether some increases in per capita income are possible while the population grows rapidly, but rather whether rapid population growth is a major deterrent to a rapid and continuing increase in per capita income. A specific example will clarify this point. If the birth rate in India is not reduced, its population will probably double in the next 25 or 30 years, increasing from about million to about million.
Agricultural experts consider it feasible within achievable limits of capital investment to accomplish a doubling of Indian agricultural output within the next 20 to 25 years. In the same period the output of the non-agricultural part of the Indian economy probably would be slightly more than doubled if the birth rate remained unchanged.
The real question is: Could India and the other less-developed areas of the world do substantially better if their birth rates and thus their population growth rates were reduced? Economic analysis clearly indicates that the answer is yes.
Any growth of population adds to the rate of increase of national output that must be achieved in order to increase per capita output by any given amount. To double per capita output in 30 years requires an annual increase in per capita output of 2.
In either instance an economy, to grow, must divert effort and resources from producing for current consumption to the enhancement of future productivity.
In other words, to grow faster an economy must raise its level of net investment. Net investment is investment in factories, roads, irrigation networks, and fertilizer plants, and also in education and training. The low-income countries find it difficult to mobilize resources for these purposes for three reasons: The pressure to use all available resources for current consumption is great; rapid population growth adds very substantially to the investment targets that must be met to achieve any given rate of increase in material well-being; and the very high proportions of children that result from high fertility demand that a larger portion of national output must be used to support a very large number of non-earning dependents.
These dependents create pressure to produce for immediate consumption only. In individual terms, the family with a large number of children finds it more difficult to save, and a government that tries to finance development expenditures out of taxes can expect less support from a population with many children.
The Center is working to put the spotlight back on human population growth. We're using creative media like our award-winning Endangered Species Condoms to start conversations on a person-to-person basis nationwide and using YouTube to explain those not quite so obvious connections between population growth and other environmental problems in short, entertaining but educational vlog videos.
We're also pushing outreach by bringing the message to museums, science centers and classrooms and through social media campaigns like CrowdedPlanet. Both men and women play a role in human population growth, but when it comes to reproductive decisions, women are disproportionately affected by a lack of empowerment and access to healthcare.
Many women are unable to get the contraception or family planning tools they want or need to make decisions about their reproductive futures. Unfortunately lawmakers are currently doing everything they can to restrict reproductive healthcare, including education and access to contraception. Reproductive rights are an environmental issue.
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