In the Midst of the Sixth Mass Extinction…

An artist's impression of a post-apocalyptic New York City skyline, with the scorched cracked earth at the forefront and an eerie yellow glow at the background.Exponential Population Growth

The World population has grown to 7 billion, and it is expected to reach over 9 billion by 2050.  In the long-term, this  growth is unsustainable, as vital resources are becoming increasingly depleted and humanity faces a number of threats to its continued expansion.  Many believe that scientists will solve these problems with new technology.  Are humans causing the sixth mass extinction?  What is the reality? 

Let’s imagine a growing population of bacteria.

These bacteria live in a bottle.  Their population doubles every minute.

An animation showing the exponential growth of a population of cyanobacteria.
Growing Population of Cyanobacteria Source: ScienceLife

At 11 am, there is one bacterium.  At 12 noon, the bottle is full.  It is half-full at 11:59, leaving only enough space for one more generation.  The bacteria see the danger, they search for new bottles and find three.  They assume that their problems are solved.  By 12 noon, the first bottle is full.  By 12:01, the second bottle is also full.  By 12:02, all the bottles are full.

This is the problem we, human beings, face due to the doubling of population caused by exponential growth.

When humanity began to use coal and oil as fuel sources, it experienced unprecedented growth.  Even though growth rates produce large increases over time, under a 1% growth rate, an economy will double every 70 years.  A 2% rate doubles it in 35 years.  At a 10% growth rate, an economy will double in only 7 years.

If an economy grows at the current rate of 3%, it doubles every 23 years.  With each doubling, demand for energy and resources will exceed all the previous doubling combined.

The financial system is built on the assumption of growth which requires an increasing supply of energy to support it.  Banks lend money they do not have, in effect creating it.  The borrowers use the newly created loan money to grow their business and pay back the debt with an interest payment, which requires more growth.

Due to the creation of this debt-formed money, most of the World’s money represents a debt with interests to be paid.  Without continual new and ever-larger generations of borrowers to produce growth and pay off these debts, the World’s economy will collapse.  Like a Ponzi scheme, the system must expand or die.

An animation showing graphical representations of the global change in rates of atmospheric CO2 concentration, atmospheric CH4 concentration, ozone depletion, tropical rainforest and woodland loss, damming of rivers, water use, coastal zone nitrogen flux, species extinction, total real GDP, telephones, motor vehicles, international tourism. All of which are on the increase.Partly through this debt system, the effects of economic growth have been spectacular in GDP (Gross Domestic Product), damming of rivers, water use, fertiliser consumption, urban population, paper consumption, motor vehicles, communications and international tourism.

World population has grown to 7 billion and it is expected to exceed 9 billion by 2050.  On a flat infinite Earth, this might not be a problem.  However, as the Earth is round and finite, we will eventually face limits to growth.  Economic expansion has resulted in atmospheric nitrous oxide N2O and methane CH4, atmospheric ozone depletion, increases in great floods, damage to oceanic ecosystems, including nitrogen run-off, loss of rainforest, increases in domesticated land and species extinction.

The Legend of the Chessboard: If you put one grain of rice on the first square of a chessboard, two on the second, and keep doubling the grains every square, there are not enough grains of rice in the World to get you to the 64th square.
The Legend of the Chessboard: If you put one grain of rice on the first square of a chessboard, two on the second, and keep doubling the grains every square, there are not enough grains of rice in the World to get you to the 64th square.

If we place a single grain of rice on the first square of a chessboard, double this and place two grains on the second square, double it again and place four grains on the third square, double again and place eight on the fourth and continue this way putting on each square twice the number of rice grains than were on the previous one, then by the time you reach the final square, we will need an astronomical number of grains:

9,223,372,036,854,776,000 grains of rice.


That’s 9 quintillion 223 quadrillion 372 trillion 36 billion 854 million 776 thousand grains of rice!!

Many more grains than the human race has grown in the last 10,000 years.

Modern economies are like the grains and the chessboard.  They double every three decades.  On which square of the chessboard are we?

Besides energy, civilisation demands numerous essential resources:

  • fresh water

  • top soil

  • food

  • forests

  • minerals and metals.

Growth is limited by the essential resources and the scarcity of their supply.  A barrel is traditionally made of wooden staves, bound by metal hoops.  And like water filling a barrel, growth can go no further than the lowest stave… or the most limited essential resource.

Humans currently 40% of all photosynthesis on Earth.  Although it might one day be possible to use 80%, we are unlikely to ever use 150% of it.


Global Food Supply

An artist's impression of deforestation, showing woodlands shaped as a pair of lungs - one of which has been logged for wood in its lower section and now just shows the bare earth.
Deforestation is only one of the issues threatening the long-term survival of mankind… Source: Foresight USA

The global food supply relies heavily on fossil fuels.  Before World War One, all agriculture was organic.

Following the invention of fossil-fuel derived fertilisers and pesticides, there were massive improvements in food production, allowing for increases in human population.

The use of artificial fertilisers has fed far more people than would have been possible with organic agriculture alone.


Fossil fuels are needed for farming equipment, transportation, refrigeration, plastic packaging and cooking.  Modern agriculture uses land to turn fossil fuels into food, and food into people.

About 7 calories of fossil fuel energy are used to produce 1 calorie of food.

In America, food travels approximately 1,500 miles from farm to customer.


Besides fossil fuel decline, there are several threats to the current system of food production.  Cheap energy, improved technology and subsidies have allowed massive fish catches.  Global fish catches peaked in the late 1980s, forcing fishermen to move into deep waters.

Nitrogen run-off by fossil-fuel based fertilizers poison rivers and seas, creating enormous dead zones.  The negative environmental effects of “eutrophication” include hypoxia – the depletion of oxygen in the water, which may cause death to aquatic animals.  At this rate, all fish populations are projected to collapse by 2048.

Acid rain from cities and industries leeches the soil of vital nutrients, such as potassium K, calcium Ca and magnesium Mg.

A map of the Ogallala Aquifer in the United States, showing the aquifer's saturated thickness at various locations in 1997.
Saturated thickness of the Ogallala Aquifer in 1997 after several decades of intensive withdrawals. The breadth and depth of the aquifer generally decrease from north to south. Source: Wikipedia

Another threat is a lack of water.  Many farms use water pumped from underground aquifers for irrigation.  The aquifers need thousands of years to fill up, but can be pumped dry in a few decades, like oil wells.

America’s massive Ogallala Aquifer is a shallow water table aquifer located beneath the Great Plains in the United States, and one of the largest aquifer in the World.  The Ogallala Aquifer has fallen so low that many farmers have had to return to less productive dry land farming.  Additionally, the use of irrigation and fertilisers can lead to salinisation – the accumulation of salt in the soil.  Salinisation is a major cause of desertification.

Still another threat is top soil loss.  Two hundred years ago, there were 6 feet of top soil on the American prairies.  Today, through tillage and poor agricultural practices, approximately half of it is gone.

Irrigation encourages the growth of ‘stem rust’ fungi, like Ug99, which has the potential to destroy 80% of the World’s grain harvest.  According to American biologist Norman Borlaug (1914-2009), father of the Green Revolution, stem rust has immense potential for social and human destruction.


Carrying Capacity of the Land

An illustrated diagram and chart showing the carrying capacity of land throughout the year for different species, including the seasonal surplus and causes for surplus decrease, i.e. starvation, disease/parasites, accidents, weather, hunting, predators...The use of biofuels means that less land will be available for food production.  An area has a finite carrying capacity.  This is the number of animals or people that can live there indefinitely.

If a species overshoot the carrying capacity of that area, it will die back until the population returns to its natural limits.


The World has avoided this die off by finding new lands to cultivate or by increasing production, which has been possible largely thanks to oil.  To continue growth, more resources are required than the Earth can provide, but no new planets are available.

In the face of all these challenges, global food production must double by 2050 to feed the growing World population.  There will be challenges in feeding over 9 billion in the years to come when World oil and natural production will be in decline.

One billion people are already malnourished or starving.


A Happy Ending?

An infographic showing the equivalent of 1.5 Earths would be required to meet the demands humanity makes on Nature each year.The global economy grows exponentially at about 3% a year, consuming increasing amounts of non-renewable fuels, minerals and metals, as well as renewable resources, like water, forests, soils and fish faster than they can ever be replenished.

Even at a growth rate of 1%, an economy will double in 70 years.

The problem is intensified by other factors.

Globalization allows people on one continent to buy goods and food made by those in another.  The line of suppliers is long, facing strains on a limited oil resource.  We now rely on distant countries for basic necessities.  Modern cities are fossil-fuel dependent.  Most banking systems are based on debt, forcing people into a spiral of loans and repayments, producing growth.

What can be done in the face of these problems?

Many believe that the crisis can be prevented through conservation, technology, smart growth, recycling, electric cars and hybrids, and substitution.  Conservation will save you money, but it alone will not save the planet.  If some people could go back on oil use, the reduced demand will drive down the price, allowing others to buy it for less.  In the same fashion, a more efficient engine that uses less energy will paradoxically lead to greater energy use.

In the 19th century, English economist William Stanley Jevons (1835-1882) realised that better steam engines make coal a more cost-effective fuel source, which led to the use of more steam engines, which increased total coal consumption.

Growth abuse will consume any energy resource saved through conservation.


Many believe that scientists will solve these problems with new technology.  However, technology is not energy.  Technology can channel energy into work, but it cannot replace it.  It also consumes resources.

For instance, computers are made with 1/10th of the energy needed to make a car.  More advanced technologies may make the situation worse, as many require rare minerals, which are also approaching limits.

90% of the World’s rare earths are produced by China – most coming from a single mine in Inner Mongolia.  These rare earth minerals are used in catalytic converters, aircraft engines, high-efficiency magnets and hard drives, hybrid car batteries, lasers, portable X-ray machines, shielding for nuclear reactors, compact discs, hybrid vehicle motors, low-energy light bulbs, fibre optics and flat-screen displays.  China has begun restricting the export of these minerals as demand for them soars.


Unsustainable Growth

A cartoon depicting planet Earth running on empty, with a population of 7 billion and low meters on fossil fuels, wilderness, fisheries and water.So-called sustainable growth or ‘smart’ growth will not help as it also uses non-renewable metals and minerals in ever increasing quantities, including rare earths.  Recycling will not solve the problem as it requires energy, and the process of recycling is not 100% efficient.  It is only possible to reclaim a fraction of the material being recycled.  A large portion is lost forever as waste.

Electric cars run on electricity.  As most power is generated from fossil fuels, this is not a solution.

Additionally, cars of all types consume oil in their production.  Each tyre alone requires about 7 gallons of petroleum.  As of 2010, there are around 800 million cars in the World.  At current growth rates, this number would reach two billion by 2025.  It is unlikely the planet can support this many vehicles for long, regardless of their power source.

Many economists believe that the free market will substitute one energy source with another through technological innovation.  However, the main substitutes to oil face their own decline rates.  Substitution also fails to account for the time needed to prepare for a transition.

The U.S. Department of Energy’s Hirsch Report estimates that at least two decades would be needed to prepare for the effects of Peak Oil.  The issues of energy shortages, resource depletion, top soil loss and pollution are all symptoms of a single larger problem: growth.  As long as our financial system demands endless growth, reform is unlikely to succeed.  What then will the future look like?


Or a Mad Max-type Future for Humankind and the Sixth Mass Extinction?

A cartoon illustrating the sixth mass extinction. The drawing shows a human skeleton lying in the middle of a desert next to a paper copy of the UN report on Global Warming. A UFO flies past over the scene and its occupants comment: "Idiots..."Optimists believe that growth will continue forever without limits.  Pessimists think that we are heading towards a new Stone Age or extinction.  The truth may lie between these two extremes.  It is possible that society might fall back to a simpler state – one in which energy use is a lot less than it is now.  This would mean a harder life for most, more manual labour, more farm work and local production of goods, food and services.

What should one do to prepare for such a possible future?

  • Expect a decrease in supplies of food and goods from faraway places

  • Start walking or cycling

  • Get used to consuming less electricity

  • Get out of debt

  • Try to avoid banks

  • Instead of shopping at big shopping malls, support local businesses

  • Buy locally-grown food at farmers markets

  • Instead of a loan, consider gardening to grow your own food and learn to preserve it

  • Consider the use of local currencies should the larger economies cease to function

  • Develop greater self-sufficiency

None of these steps will prevent collapse, but they might improve your chances in a low-energy future, one in which we will have to be more self-reliant, as our ancestors once were.

Are we irrevocably setting ourselves for the sixth mass extinction – our own?