Once the human race nearly went extinct

Kiloyears = 100 years. Source: Interesting Engineering.

The human race once nearly went extinct.  That’s the conclusion of a study published in the current issue of Science magazine.

During most of human history, it is believed that there were fewer human beings in existence than now live in the U.S. city (Rochester, N.Y.) where I reside.  They all lived in Africa.  There was a period estimated to be 117,000 years long when the human race dwindled down to fewer than 1,300 people.

The scientists who did the study think the human race was threatened by climate change, and responded to the threat by discovering the use of fire.  But there are many uncertainties about just what happened.

Today’s world population is estimated at 8 billion people.  I suppose, mathematically speaking, that means there are better odds of a remnant surviving a mass extinction event, even as population growth increases the possibility of catastrophe.

Still, it is sobering to think that the survival and present-day existence of the human race is something that – at least according to this study – could so easily have not happened.

LINKS

Early ancestral bottleneck could have spelled the end of modern humans by the Chinese Academy of Sciences.

Here’s when human beings nearly went extinct by Sade Agard for Interesting Engineering.

Extreme cold may have wiped out human ancestors 900,000 years ago by Bruce Bower for Science News.  [Added Later].

Only 1,280 Breeding Humans Once Roamed Earth, Gene Study Suggests by Isaac Schultz for Gizmodo.  [Added Later].

The rising human tide in Africa

“If the biggest global news story of the past 40 years has been China’s economic growth,” wrote demographer Paul Morland, “the biggest news story of the next 40 years will be Africa’s population growth.”

In his book, The Human Tide, Morland traced what’s called the demographic transition in society after society, from Britain and Germany to China and India.  The pattern is that societies experience surges in population when the death rate falls and life expectancy increases, but then the fertility rate levels off and then decreases.

In many parts of the world, including North America, Europe, Russia, China and Japan, the fertility rate is below 2.1 children per woman, which is the replacement rate.

In general, each successive society that underwent this transition had a bigger and more rapid surge in population than the ones that went before, but also a more sudden drop.  The latest region of the world to begin the demographic transition is sub-Saharan Africa, and that part of the world is still in the early stages of its population surge.

United Nations statistics quoted by Morland show that:

• Of the 48 states and territories with fertility rates of 4 and above, all but seven are in sub-Saharan Africa.
• Nine out of 10 countries with the highest fertility rates are in Africa.
• Every one of the 30 countries with the lowest life expectancy are in sub-Saharan Africa.
• All but two of the 30 countries with highest infant mortality rates and the lowest median age are in sub-Saharan Africa.
• The population of sub-Saharan Africa is growing more than twice as fast as the world as a whole.

Fertility rates in Africa are falling, just as in the rest of the world, and Morland is confident they will continue to fall.  But they are falling from such a high level that there will be a population surge regardless.  Population growth depends not only on how many children the average woman has, but how many women there are of child-bearing age.

My knowledge of Africa is superficial, but it is obvious that conditions in sub-Saharan Africa are bad.  Much of Africa is at risk of famine.  Africa is torn by war and ravaged by drought—which can only get worse, as global temperatures rise.  Corruption is prevalent.  Although there are bright spots and encouraging signs, most African governments still are on a spectrum from corrupt semi-democracies to dictatorships for life.

I have to say that I have a good impression of African immigrants in the USA—not only highly educated professionals from Nigeria and Kenya, but also poor refugees from Liberia, Sierra Leone, Sudan and Somalia, whom I got to know as a volunteer driver years ago for a Catholic refugee resettlement charity here in Rochester, N.Y..

Most of the refugees struck me as having great resilience, great personal dignity and a strong desire to repay the least little kindness.  Somali refugees were moved into a section of a public housing project, and the smell of Somali home cooking replaced the smell of marijuana in the hallways.  The managers were glad to have tenants who didn’t drink alcohol or take dope, play loud music late at night or get into fights in which the police had to be called.  From what I’m told, they’ve all thrived since.

Preparing for an age of population decline

The fertility rate in virtually all countries is declining.  The fertility rate in much of the world, including North America, Europe, Russia, China and Japan, is already below the replacement rate of 2.1 children per average woman.

If this goes on, world population will peak soon after the end of the century and start declining.  Populations of a few countries are declining already.

This is good news.  All other things being equal, it means less danger of famine, less pressure on the environment and less competition for scarce resources.

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But there are problems, too.  One is decline of nations as their populations become older and smaller.  Another is a change in the world balance of power during the transition, as some nations shrink while others continue to grow.

Two Canadian writers, Darrell Bricker and John Ibbitson, explored these issues in a new book, EMPTY PLANET: The Shock of Global Population Decline.

The fertility rate is 1.4 in Japan and 1.1 in South Korea.  In the short term, this means an ever-larger elderly population that must be supported by an ever-smaller working age population.  I don’t think it is an accident that Japan has more robots per person than any other country.

A younger population tends to be more ambitious, innovative and warlike.  An older population tends to be more cautious and peaceful.  Older populations consume less, which is a good thing—but not for a capitalist economy, which requires growing markets.

In the long run, unless there is a change of direction, countries with low fertility rates could literally die out.  Americans and Canadians, with fertility rates of 1.8 and 1.5, have kept up national population numbers through immigration.  But the Japanese and South Koreans accept virtually no immigrants.  They see immigration as a threat to their racial and cultural purity.

In the short run, Japan and South Korea face economic decline and, in the long run, a slow fading from the world scene.  All countries whose birth rates fall below the replacement rate will face this dilemma sooner or later, the authors wrote.

Demographers have a term, “the population transition.”  It describes how countries go from having a high birth rate and high death rate to a high birth rate and low death rate (a population explosion) and end up with a low birth rate and low death rate.

This is often attributed to growing wealth, but Bricker and Ibbitson argued that the key factor is cultural change.  It is a combination of:

• Feminism, women gaining control of reproduction and finding opportunities outside the home.
• Urbanization, people moving to cities where, unlike on the farm, additional children are no longer an asset.
• Modernity, people living for themselves instead of to perpetuate a family, faith or nation.

Feminism, urbanization and modernity explain how the fertility rate in Brazil, a poor country, can be 1.7,  well below the 2.1 replacement rate and below the 1.8 fertility rates of the United States and the United Kingdom.  This is good news because it means that the population transition can take place without the whole world adopting the American consumer culture.

When religion and nationalism are strong, fertility rates, all other things being equal, are likely to be high.  Loyalty to faith and nation  likely explain why the Israeli fertility rate is 3.1 and the Palestinian rate is 3.9.

World power and the rise and fall of population

Modern-day demographers view the nations of the world at different stages of what’s called the demographic transition.   And what stage they’re in has a lot to do with their power on the world scene.

There are nations at an early stage of the transition, with high fertility rates (number of births per woman).  There are nations at a middle stage of the transition, with fertility rates falling but population still growing.  And there are nations at the end stage of the transition, where the fertility rate is less than needed to replace the current population.

A demographer named Paul Morland, in a book called THE HUMAN TIDE: How Population Shaped the Modern World, explained how population growth and decline is related to geopolitical power.  There are nations with small populations that are rich, and there are nations with large populations have been poor and weak, but there are no nations that are both small and powerful.

The first nation to undergo the modern demographic transition was England, Morland’s own country.  In the days of Queen Elizabeth and the Spanish Armada, England was small and poor, compared not only to France, which was Europe’s largest nation, but also to Spain.

The high English birth rate enabled the English to grow strong and to found new nations—the USA, Canada, Australia and New Zealand.  In 1870, the English fertility rate was six children per woman.  British statesmen such as Cecil Rhodes foresaw a day when the English would overrun and rule the planet.

The high fertility rate of Anglo-Americans in the early 19th century explains their belief in their “manifest destiny” to create a nation that stretched from the Atlantic to the Pacific.  Mexico was no match for the USA because its population growth had not yet taken off.  Texas and California were virtually empty when Anglo settlers poured in.

The demographic transition began in the 20th century.  The English fertility rate was down to three children per woman in 1914 and down to about two in the 1920s and beyond.

The English and French feared the higher German fertility rate.  They may have been more willing to go to war in 1914 than they otherwise would have been, because they feared Germany would have had a greater population advantage in the future.

The Germans, in turn, feared the higher Russian fertility rate.  They may have been more willing to go to war with Russia for the same reasons that the English and French were more willing to go to war with them.

Russia benefitted from its population surge.  During the Second World War, the Red Army suffered many more casualties than the Wehrmacht, but won not only through its courage and fighting ability, but its greater numbers.  If the opposing forces on the Eastern Front had been equal in numbers, Nazi Germany might have won the Second World War.

Now the fertility rate is below the replacement rate in all these countries—the USA (including all races and demographic groups, not just Anglos), the UK, Germany and the Russian Federation.

Americans, English, Germans and Russians are no longer spreading through the world.  Instead Mexicans have been moving into the United States, citizens of the former British Empire are moving into the UK and the formerly subject peoples of Central Asia are immigrating into the Russian Federation.

Morland’s history covered many other nations and all the world’s regions.  He did not of course claim that population is the only factor in world power, only that it is an important one.  There is a correlation, although not a perfect one, between the rise and decline of economic and military power and the rise and decline of population.

A world on the move

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Source: peoplemovin – A visualization of migration flows.

If you click on the link (above), you can find the number of migrants into and out of every country, and also a breakdown of the destinations of emigrants from every country and the sources of immigration into every country.   I think this is interesting, and maybe you will, too.

These figures reflect total numbers of peoples living in a country other than the one in which they were born, as of the year 2010.  They do not reflect recent events, such as the Ukrainian civil war or the Syrian refugee crisis.

World on track for zero population growth

Much of the world is on track for zero population growth.  Birth rates in many countries are at the replacement rate of 2.1 children per average couple, or lower.

The change, in my opinion, has come about because (1) knowledge and availability of birth control are widely available, (2) women are emancipated and have control over their bodies and (3) people are raised far enough out of absolute poverty that they think it is better to have a small number of prosperous, well-educated children than to have many children.

I think that, in the long run, Muslims and Hindus will be as willing to practice contraception as Catholics have proved to be.

Why I am not a population bomber

In 1968 I read a book entitled The Population Bomb by Paul Ehrlich which began as follows:

The battle to feed all of humanity is over.  In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate…

via Wikipedia.

Ehrlich argued that the world’s fundamental problem was that there were too many people in the world, and that the only solution was by means of birth control if possible, but not by relief of poverty or increase of food supply.

At the time he wrote, there were 3.5 billion people in the world.  Now there are 7.2 billion, but there is less hunger and starvation in the world than there is today.

Nowadays Ehrlich admits he exaggerated for dramatic effect, but he says it was for a good purpose, which was to alert people to the danger of overpopulation.

I don’t agree it served a good purpose.  I think Ehrlich put obstacles in the way of people such as Norman Borlaug who sought to increase food production and relieve famine.  What good was it, people asked, if it results in more people being born who eventually would starve to death anyway?

Mathusianism has long been used as an excuse to let people starve.  The British government used this excuse for failing to relieve famine in Ireland in the 1840s and in India in the 1940s.   It is still used as an excuse for failing to relieve famine in Africa.

The great economist, Amartya Sen, has pointed out that there never has been a famine in a democracy, because in a democracy, public opinion will not permit allowing a large percentage of the population to starve.

In modern times, the problem has never been that there was not enough food to go around, he wrote.  The problem was people who were too poor to buy the food that was available.

Yet Ehrlich’s ideas still have wider circulation than Sen’s, at least among people I hang out with.  I still hear people say, when we’re talking about some social problem, that the basic underlying problem is that there are too many people in the world.

And sometimes this is followed—and this makes my blood run cold—by the remark, “We’ve got to thin the herd.”

The best thing I can say for people who talk like this is that they don’t realize the genocidal implications of what they’re saying.

The young nations and the aging nations

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I think the leveling off of population growth is a good thing.  There is a limit to how many people the earth can support.  I don’t claim to know what that limit is, but it will be passed at some point unless population growth is leveling off.

The good news is that this is starting to happen.  The problem is that it is not happening in every nation at once.

Some nations have low birth rates and an aging population that is growing in relation to the working-age population.  Other nations have high birth rates and a young population who can’t all find jobs.

Should there be more immigration from the growing young nations to the static older nations?

What happens to the world balance of power when the population of some nations is static and the population of others grows?  If present trends continue, India will have a larger population than China.  Mexico could become a more populous nation than the USA.  What then?

Bertrand Russell years ago wrote that in order to achieve world peace, nations needed to limit their populations as well as limit their armies and armaments.  Is that possible?

Demographers say that a nation’s population growth starts to level off when women are emancipated enough to be able to decide whether or not to have children, and when a nation reaches a level of prosperity such that parents think their security in old age is better with a few well-educated and well-off children than with many poor children.

I hope this comes true for the whole world.  Expressing this hope is as close as I can come to answering the questions I asked.

What do you think?

The population bomb that fizzled

When I feel most pessimistic about the state of the nation, I remind myself of all the things I worried about in the past that never came to pass.

In the 1960s, I read books such as Paul Ehrlich’s The Population Bomb and William and Paul Paddock’s Famine – 1975! warning of imminent mass starvation because of world population growth. These two books weren’t unique; they are the ones I remember most vividly.  Ehrlich described very graphically the horrors that lay ahead, and warned of the futility of trying feed the teeming masses, because they would only reproduce and create a larger starving population. I recall the expression “dieback” to describe how nature would bring population and resources into balance.

Later on there was something called “liferaft ethics,” which said that the Earth is like a liferaft that can carry only a limited number of people, and that if you are on the liferaft (i.e., a citizen of a fortune country such as the United States), you are justified in pushing away someone drowning in the water to save yourself. Norman Borlaug’s efforts to introduce high-yield crops in India and elsewhere met with active hostility from the population warriors.

Now nations such as China and India, which were thought to be doomed, are successfully raising their material standard of living. If their populations are poor by American standards, they aren’t starving. Where starvation still exists, as in North Korea, it is the result of oppressive government and a failed economic system, not overpopulation.