September 19, 2014
World Population To Hit 11 Billion In 2100 Due To Africa Growth

Our overpopulated future.

Using modern statistical tools, a new study led by the University of Washington and the United Nations finds that world population is likely to keep growing throughout the 21st century. The number of people on Earth is likely to reach 11 billion by 2100, the study concludes, about 2 billion higher than widely cited previous estimates.

Previous estimates of a 9 billion person max are looking less likely.

“The consensus over the past 20 years or so was that world population, which is currently around 7 billion, would go up to 9 billion and level off or probably decline,” said corresponding author Adrian Raftery, a UW professor of statistics and of sociology. “We found there’s a 70 percent probability the world population will not stabilize this century. Population, which had sort of fallen off the world’s agenda, remains a very important issue.”

Write off Africa's big animals. Lions, leopards, cheetahs, servals, and caracals are all going to get wiped out. Ditto the African elephant, cape buffalo, rhinoceros, giraffe, hippo, pygmy hippo, wildebeest and zebra. Wild areas are already shrinking as rapid human population growth means more farms, bigger cities, more logging, more poaching.

My fear: natural selection will boost alleles that raise fertility and human population will grow way beyond 11 billion. Then a far greater environmental catastrophe will ensue.

Share |      Randall Parker, 2014 September 19 07:47 PM 

destructure said at September 20, 2014 3:53 AM:

What a coincidence. I was just reading an article about the Ebola virus in Africa. Aparently, many Africans still believe the virus doesn’t exist. So when a delegation of eight doctors, healthcare workers and journalists traveled to Guinea to educate them on how to avoid spreading the virus an entire village chased them down, stoned them and hacked them to death with machetes. There also were reports that 21 people had been injured. A local police officer, Richard Haba, said the villagers believed that Ebola “is nothing more than an invention of white people to kill black people.” I don't think Africa has the potential to industrialize or get its population problems under control. At least not on their own. They're going to have to be advised and managed by benefactors from the outside or the entire continent will go to hell and take the rest of the world down with it.

jhill said at September 20, 2014 7:01 AM:

I am going to have a party in Jacksonville Florida and everyone is invited. At that party I am going to give every family group of four a 1200 square foot house in Texas. Isn’t that a nice story? Perhaps you did not fully grasp it – let me try again. I am going to have a party in Jacksonville Florida and every human being on earth is invited. Jacksonville would give every human being more space than they would have at a normal party. Then I would give every family / group of four people a house in Texas. That would take up about half of the state of Texas. Realistically all seven billion human beings could easily fit in the United States with plenty of open space left over and more than enough farm land to feed every one of them. Today’s technology is capable of handling seven billion people in the United States. To suggest that 80 years from now the United States (let alone the world) could not handle 11 billion people is unfathomable. I think you should read your own blog more about future technology - It is is quite good!


B. T. Pirate (a force for autism) said at September 20, 2014 8:15 PM:

Absolutely, jhill. An America packed with 11 billion (swarthy) people surely would be a healthy society.

B. T.

aandrews said at September 20, 2014 10:04 PM:

I have a book recommendation for you, jhill.

The Tyranny of Magical Thinking, by George Serban.

Randall Parker said at September 20, 2014 11:38 PM:


I will give you specific facts to contend with: The price of beef hit $5.28 per pound in February, highest since 1987. Farmers have sold off herds due to high feed costs. Why does the grain cost more? Rising demand from industrialization, population growth, and expensive oil (causing more corn to be used to make ethanol). Why isn't US farm land expanded to grow the additional crops needed for a mere few hundred million people. Because the land in production is higher quality than the land which is not in production.

Another problem: drought. Even before the drought plains farmers were already over pumping the Ogallala aquifer and farm production in Kansas will peak by 2040 due to aquifer depletion. Imagine what would happen if a few billion people were brought to the US and farmers tried to grow enough food for them all.

The sustained high cost of grain demonstrates that the market can't respond by producing much more food. If cheaper ways to do it existed farmers would already be using them.

James Bowery said at September 21, 2014 8:19 AM:

As I just posted over at nextbigfuture:

He hasn't covered this. When you have a country like Bangladesh, with a history of flood-induced famine, convert to flooding-immune floating photobioreactors that cost under $100,000 per hectare capital expense and produce 100 to 200 metric tons dry mass of high protein, high omega-3 oil per hectare year in a 1% biomass concentration growth medium (concentration is critical for energy efficient separation) -- and does so without competing for land area, you have a story that is worth covering. Do you disagree? BTW: I sympathize with Brian's difficult position w/re algae stories. The signal to noise ratio in this area is very low with people making all kinds of bold-yet-vague claims and hundreds of millions of dollars being poured down a variety of rat-holes. But one thing is for damn certain: You won't find figures like those I just provided -- figures absolutely essential to calculating a price point -- provided in those other stories. So really, he should cover this.

Actually, as I've been telling people, what this ultimately does is transfer civilization from land to the ocean doldrums.

Delaying the introduction of this technology is causing untold extinctions as well as human suffering.

Brett Bellmore said at September 21, 2014 11:33 AM:

"and expensive oil (causing more corn to be used to make ethanol)."

Expensive oil isn't causing corn to be used to make ethanol. LEGAL MANDATES are causing corn to be used to make ethanol. Nobody would be putting ethanol in their tanks otherwise, it damages many engines, and results in poor mileage. The ethanol mandate isn't a response to oil prices, it's just a giveaway to ADL.

jhill said at September 21, 2014 11:44 AM:

Aandrews thank you for the excellent book recommendation – I look forward to reading it. I would ask that you re-read your recommendation then read Thomas Malthus “An essay on the principle of population”. You should follow it with Paul Erlich’s “Population Bomb”. Optional reading would then be “Population Matters” by Julian Simon.
Using your book as a reference it is obvious – no matter how many times the population issue is debunked and made to look foolish (childish if you want to look at in terms of your book) there are some people who still cling to it.
Randall – to your point – you seem to think that the price of beef is a measure of whether or not people can eat? Remember at the time of Malthus about ninety percent of the world economy was food. His mistake is more forgivable. Now the percentage is dramatically less yet we have more people.
If you believe that we will continue to make technological progress then there really should be no debate. America could easily handle 11 billion people in 80 years.

jhill said at September 21, 2014 11:48 AM:

FYI for those that don't know - Malthus publication was 1798 and erlich was 1968.

James Bowery said at September 21, 2014 12:47 PM:

jhill, give it up. Randall didn't say anything about the US's carrying capacity. Its obvious you're a genocidal maniac with only one objective: Take the land from the Nation of Settlers and destroy their culture where culture includes their very biological existence as a uniquely interesting -- particularly in the age of ocean and space settlement possibly opening up -- people. Pure evil.

James Bowery said at September 21, 2014 1:11 PM:

Ah, I stand corrected -- you managed to lure him into responding to you about the US as opposed to Africa.

My point stands as to what you're up to. Even if the algae technology I propose is adopted and expands to its full potential of multiplying the carrying capacity of the world by a factor of 20 -- that doesn't mean they all have to move onto US territory to replace the population lost to a theocracy preaching to the Nation of Settlers self-hatred. Indeed, it means they can stay where they are and the Nation of Settlers can adopt a total fertility rate closer to that they enjoyed in the 1800s. But that just wouldn't do would it?

bob sykes said at September 21, 2014 1:36 PM:

This prediction is nonsense. The correct prediction is the UN's low projection, which the world has actually been following for 30 years or more. This projection has a maximum population of 8 to 8.5 billion around 2030 and a slow decine thereafter.

The higher projections involve a number of assumptions that are contrary to current and past experience. For example, the median projection assumes that all countries have replacement level reproduction or higher. This would require a near doubling of reproduction rates in Europe and East Asia, which is against the long term trend everywhere. In fact reproduction rates are also falling in Africa, although they remain high.

Bet on falling world population beginning in about 15 years.

The world will be cooler, too.

And Europe and North America will be full-blown socialist police states.

Rasputin said at September 21, 2014 4:53 PM:

Malthusian limits are sure to reassert themselves. Baring a technological Singularity, which would shift events beyond the human, human history is cyclical, a cycle of gain and loss. We are currently going through a population spike; it may grow larger before it falls, but then it will just have further to fall. Debating how many people could theoretically fit in Jacksonville or Texas or wherever, is irrelevant because it ignores the fundamental game theoretical considerations which underpin real political and economic decision making processes. You might as well be debating how many angles could fit on a pin head.

Unfortunately, a future of everyone living happily ever after, like some big gelatinous mulatto, isn't going to happen. Importing the third world to the first world isn't magically going to solve anything - all it's going to achieve is to turn the first world into the third world, and everyone would be worse off for it.

destructure said at September 21, 2014 9:23 PM:

The word's entire population could fit in the grand canyon. Do you know why they don't do it? Because it would really, really suck. Here's a picture of it.

Randall, could you check jhill's to see if he's not our little foreign friend reincarnated under a new name.

Greg O said at September 23, 2014 11:44 AM:

+1 to Bob Sykes.

The 11 Billion number is nonsense.

You can download the data yourself from the UN website, stick it in excel and then just do some quick derivatives (changes year over year and then rate of change). What you quickly find is the third derivative (change to the rate of change) has been and is negative. and that the rate of change goes negative sometime in the middle of this century. The top projections from the raw data is in the neighborhood of 10 billion.

AbelardLindsey said at September 23, 2014 1:27 PM:

Bob sykes: You are correct about population projections outside of Sub-Saharan Africa. The rest of the world's population will indeed peak around 2030, then slowly decline from there. However, you are incorrect about Africa.

The problem is, which drove the generation of the UN report to begin with, is that Sub-Saharan African fertility remains high. The report assumes a minimum of two doublings of Africa's population, along with a slow decline in the rest of the world. This is not an unreasonable assumption. Mean per capita income of Africa is already comparable (and in some cases higher) to that of India. India has a TFR of 2.6 and is falling fast. Africa's TFR is something like 4.5 and is not falling much. The usual methods of birth control - economic growth, increased literacy (especially females), increased opportunity, etc. - methods that work even on middle-eastern muslims, do not seem to be working in the case of Africa.

Mr.Spacely said at September 24, 2014 6:59 PM:

The 11 billion number assumes that sub-Saharan African nations will continue to be misruled and badly governed throughout the 21st century. That isn't fair or likely - most of these nations have only been self-governing since 1960 or later. Economic conditions can only improve in many of these nations, and economic growth combined with improved education for girls has proven to be the most effective antidote to unrestrained population growth in India and China (both of which began self-rule anywhere from 15 to 25 years before most African nations). As African nations and their governments mature, as their economies grow and diversify, and as women are increasingly able to substantially increase a family's wealth by working outside the home, African over-population is likely to become a non-issue.

Ronald Brak said at September 25, 2014 2:26 AM:

It's hard to believe that African Nations won't go through the demographic transition that all richer coutries have. Having a combination of oil wealth and a state strong enough to oppress women might boost birth rates, but that's not a combination that may come up in Africa, and as for Africa's most populous nation, I don't think there is any force in the universe that will keep Nigerian women down for long.

Nick said at September 25, 2014 6:03 AM:

"bob sykes said at September 21, 2014 1:36 PM:
This prediction is nonsense. The correct prediction is the UN's low projection, which the world has actually been following for 30 years or more. This projection has a maximum population of 8 to 8.5 billion around 2030 and a slow decine thereafter.

The higher projections involve a number of assumptions that are contrary to current and past experience. For example, the median projection assumes that all countries have replacement level reproduction or higher. This would require a near doubling of reproduction rates in Europe and East Asia, which is against the long term trend everywhere. In fact reproduction rates are also falling in Africa, although they remain high.

Bet on falling world population beginning in about 15 years."

I was at a major scientific institution in Washington 10 odd years ago, and remember studying this then. The UN at the time did publish its best estimate - since then it has gone on to publish the highest. One doesn't have to think very hard to figure out why.

They are now talking about up to a million ebola cases (worst case) by early next year. The above projections (best estimate, highest estimate) don't take into account disease, famine, or war. War is on the rise across Africa, disease is rearing its head, and when the continent is a teaming mass, the world will likely not respond well, and starvation will come up from behind. The Four Horsemen are coming to Africa. Unless the populace there responds better than slaughtering the doctors who have come to treat them, I would bet on the low African population growth estimate.

Engineer-Poet said at September 25, 2014 7:22 AM:
Unless the populace there responds better than slaughtering the doctors who have come to treat them
Ignorance is curable, but you can't fix stupid.
Randall Parker said at September 25, 2014 8:29 PM:

bob sykes,

Suppose you have 2 countries with 100 million people each. Suppose that in one country women have 1 baby and in the other country women have 3 babies. In the short term the average fertility is 2. But what about the long term? Average fertility rises if the women in the 3 baby country have babies who also have 3 babies.

In the long term low fertility countries do not matter because they contain a smaller and smaller fraction of the wombs. Unless higher fertility countries drop down to 2.1 or fewer babies per woman they will keep on expanding and overwhelm all the other countries with people.

Also, in the low fertility countries the selective pressure is intense to raise fertility. Why won't it? Natural selection is powerful and everywhere and relentless.


You are missing my point. Yes, we will have technological progress. But it is by no means certain that the technological progress will be faster than the things going wrong. Technological advances in recent years have not been fast enough to prevent the rises in grain and meat costs or the sustained rise in the price of oil. These bad trends show that technological progress isn't always as fast as needed.

In my post Innovation Costs For Maintaining Civilization I argued that a substantial chunk of all innovation has to go to maintaining the living standards we already have. In my view innovation costs are rising. We need to innovate even faster to run in place. The denser the population and the greater the resource depletion the more innovation we need to compensate for it. The rising price of beef is a warning sign to me that we aren't going fast enough. The price of oil is another sign.

I've commented on the slowing of tech outside of computer tech in recent decades. So has Tyler Cowen. I am impressed that that in his Zero To One book Peter Thiel has noticed the slowing of technological progress since 1970. Maybe this is a temporary lull. Time will tell. But right now we aren't getting the advances in energy and other fields needed to compensate for the things that are going wrong (resource depletion, population growth in the poorest countries).


So then colonial occupation of South Korea and Taiwan by Japan until 1945 are to explain their low (wait, I'm confused) living standards? How about Hong Kong? Held back by Britain until 1987 and looking at decades of poverty to recover from this?

Ronald Break said at October 1, 2014 11:17 AM:

Once the smart world stops taking responsibility for the stupid world (no more NGOs, no more missionaries, no more famine relief, no more medical aid, no more acceptance of stupid immigrant overflow, and so on) watch the population numbers in the stupid world begin to level off.

Most people do not understand the concept of "innovation." It is not a linear process. But it's highly reliant upon smart and healthy people in the population. Africa has a lot of people, but not so many smart and healthy people.

Ronald Brak said at October 1, 2014 9:16 PM:

I was wondering where the Mirror Universe me had gotten to.

LoboSolo said at October 3, 2014 5:05 AM:

Now for a reality check:

If life expectancy worldwide stabilizes at 75 years, the world death rate would stabilize at 13.3 and a falling world birth rate would intersect a rising death rate around 2030. At about this time, world population growth would stop, which is consistent with the convex growth projection.

Tom Mazanec said at October 7, 2014 4:01 AM:

If we don't get this ebola thing stopped FAST, the African population in 2100 might be a lot lower than expected.

Nick G said at October 14, 2014 11:23 AM:


One of your indicators has been skewed: grain and meat prices. The US used to subsidize farmers by giving them money directly: that reduced food prices to artificially low levels, driving many farmers out of business in developing countries like Mexico.

The US has switched directions 180 degrees by mandating ethanol and raising food prices sharply. Farmers are even happier, but consumers are feeling whiplash from the reversal in pricing.

Tom Mazanec said at October 16, 2014 5:24 PM:

He projects a peak at 7.07 billion in 2025. Aren't we at least that high in 2014, and still growing? The only thing I can see that would make his projection accurate would be a worst-case ebola pandemic and/or global nuclear war, which he does not consider.

Shon Bradly said at February 21, 2015 11:39 PM:

The larger the Human population grows the more awful it is going to be when the population bubble "pops", as all bubbles do.

The population of Ethiopia was 39.5 million at the time of the famine in 1984.

It was 94 million in 2013.

The population was too large for the region to support 30 years ago and aid agencies & charities poured in food and have helped double the population.

Now much of the population of this region dreams of moving to Europe to escape the problems of this region, many of which are caused by over population.

What a mess well meaning, but ultimately foolish people in the West have created for others, as well as itself!!!

Bob Foster said at October 6, 2015 10:45 AM:

Easiest way to slow Africa down is to stop all the aid. People are thriving in a country that can't sustain itself without world vision. May sound cruel but it's kinda like truthfully shouldn't exist due to the environmental conditions. Not trying to be rude but, it's true.

Post a comment
Name (not anon or anonymous):
Email Address:
Remember info?

Go Read More Posts On FuturePundit
Site Traffic Info
The contents of this site are copyright ©