Countries can have incentives both to overcount in regions vying to demonstrate increased need for aid, say and undercount their populations perhaps to disfavor a disliked minority group.
If estimating populations is hard, estimating population trends is much harder. The demographers who estimated a ruinous, extremely fast growth trajectory were wrong, but how could they have known that the trend they were observing was about to reverse? But some organizations and institutions have done surprisingly well.
These reports have turned out to be surprisingly accurate. Since the UN has been making population projections since , and since it publishes revisions and corrections to those projections over time, we can compare its initial estimates to the revisions and corrections.
Researcher Nico Keilman did that, and found that the UN has an impressively accurate track record at population predictions. Their estimates of world population by , published in , were off by about 12 percent. They quickly got better: By , those estimates were off by only about 2 percent. Since then, the UN has pegged global population growth rates pretty precisely. So up to the present day, the UN has been highly reliable in predicting global population trends.
Its prediction now is that the world population will continue to increase until , when it will peak at Nonetheless, they have their critics. These models expect fertility in low-income countries to fall faster than the UN projects it will. Some of the differences are simply methodological. How the fastest-growing countries in the world are modeled has a huge impact on how global population models come out overall, so small differences in expectations in those countries can significantly shift overall results.
But much of the difference in projections may be rooted in disagreement over another question: how many people the world can handle. But technology — including green and sustainable technology — has been rapidly improving for a long time. The year is more than 80 years from now, and almost all the technology that we have today to make civilization sustainable sounded like wild science fiction 80 years ago.
If, for example, climate change drives currently developed countries back into poverty and drives their birthrates back up, the estimates are poorly equipped to account for that. On the other hand, if more reliable contraceptives are developed and virtually end unintended pregnancies the world over, birthrates could fall much faster than predicted.
Nonetheless, this disagreement obscures a lot of agreement. Everyone now agrees that without any totalitarian or coercive measures, populations will start declining; the big disagreement is simply when. It implies both good things — that coercive population controls will never be necessary — and concerning ones, like that societies will age and have a shrinking workforce.
But on the whole, we are much better positioned for sustainable growth than it looked in , and the fall in rich-country birthrates is why. The connection between societies growing wealthier and people desiring smaller families is pretty straightforward.
In richer societies, people do not need their kids to do labor and support the family, and they typically invest money and other resources in their kids, to give them the best shot possible at a decent life.
The connection between drops in child mortality and smaller desired family sizes is less obvious. Indeed, at first, when child mortality falls, the population shoots up, as people are still having lots of kids, but more of them survive to adulthood. That produces a rapid increase in population. That was the state of the world in the s, and some parts of the world are still in that state now.
But then, overall growth rates started to fall. Demographers think of this process as occurring in five stages. First, birthrates are high but so are death rates, and the population is low but stable when child mortality is high, people have lots of children to reduce uncertainty. Then, in the second stage, technology helps more kids survive to adulthood.
Birthrates remain high, and the population grows rapidly: for one or two generations. In the fourth stage, birthrates fall and the population stabilizes. Here we will cover both causes and effects of overpopulation in order for you to have a more informed view of the risks that come with it.
Causes of Overpopulation are different for many countries but are mostly associated with poverty, reduced mortality rates, poor medical access, poor contraceptive use, as well as immigration.
With overpopulation comes a decrease in resources and an increase in symptoms of illness and disease. There are a number of factors that contribute to overpopulation.
These are the leading causes:. Poverty is believed to be the leading cause of overpopulation. A lack of educational resources, coupled with high death rates leading to higher birth rates, result in impoverished areas seeing large booms in population.
The effect is so extensive that the UN has predicted that the forty-eight poorest countries in the world are also likely to be the biggest contributors to population growth. Their estimates state that the combined population of these countries is likely to balloon to 1. This issue is exacerbated in underdeveloped areas. As distressing as it may be to hear, child labor is still used extensively in many parts of the world.
UNICEF estimates that approximately million children are currently working, primarily in countries that have few child labor laws.
This can result in children being seen as a source of income by impoverished families. Furthermore, children who begin work too young also lose the educational opportunities they should be granted, particularly when it comes to birth control. Improvement in medical technology has led to lower mortality rates for many serious diseases. Particularly dangerous viruses and ailments such as polio, smallpox and measles have been practically eradicated by such advances.
While this is positive news in many ways, it also means that people are living longer than ever before. Though it only plays a minor role in comparison to the other causes of overpopulation, improved fertility treatments have made it possible for more people to have children.
The number of women using various fertility treatments has been on the rise since their inception. Now most have the option of conceiving children, even if they may not have been able to do so without such treatments. Unchecked immigration into countries may lead to overpopulation to the point where those countries no longer have the required resources for their population.
This is particularly problematic in countries where immigration numbers far exceed emigration numbers. Current World Population 7,,, Net Growth During Your Visit 0. You can make a big difference. Clinic Monitoring. More than 27, people used a Planned Parenthood widget from East Los High 's website in the first month of broadcast. Web Analytics. Married women who listened to Yeken Kignit in Ethiopia increased their use of family planning by Endline Research. Tell Us Your Story. Learn More.
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