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The question isn’t if it will stop, but when
Update 2022: Since I originally wrote this article, the scientific community is reaching a consensus that we are in the midst of the 6th mass extinction called the Holocene extinction. This 6th great mass extinction is being caused by humanity itself.
Table of Contents
This Human Population Growth Chart illustrates the exponential growth of the human race and the consumption of non-renewable resources. Now imagine every person in the world during the modern age emitting 6 metric tons of greenhouse gases and pollution. Now double that number (and the amplitude of this graph) to account for all the oxygen used in the combustion process (half turns into water). Furthermore, because oxygen is used in every aspect of life, not just burning fuel, but also in the manufacturing process (especially chemicals and plastics) and the destruction of all those products through oxidation (rotting, burning, rusting), triple the amplitude yet again and this represents a conservative estimate of the oxygen consumption of the human species.
I read The Population Bomb when I was a kid. I still have the edition you see pictured here. Obviously, it made a big impact on me, and the predictions keep coming true. The saving grace so far has been humanity’s ingenuity, particularly the invention of modern farming practices.
Join our Global Oxygen Depletion Facebook Page and follow some current thinking, and maybe lend some of your own. And stay tuned for Scott’s upcoming book Breathless. Join our mailing list to get news.
How often do mass extinctions occur?
This chart is from Wikipedia and it shows the frequency of mass extinctions for the last 542 million years. It is easy to see that they occur in regular intervals of about every 64 million years. The last big extinction event, the one that wiped out the dinosaurs, happened 66 million years ago. In other words, we are 2 million years overdue.
Update 2021: I’m still working on this. It’s been a tough project, but I plan to publish soon one way or another.

Sources
The United Nations Population Division, U.S. Census Bureau, U.S. Department of Energy, Wikipedia, and many more.