A strong case can be made that our Earth and its finite store of natural resources are being stressed to the limit by a human civilization that has expanded to unprecedented scale. The human population has doubled to nearly 7.5 billion in just the last 50 years. It could grow to 10-12 billion before the end of this century.
Nature has a range of deadly ways of responding to stress. Extreme weather – floods, droughts, wildfire, and super storm systems – is one example of nature’s push back against human over-exploitation.
The natural mechanism that frightens me the most is infectious disease. There are dense, heavily stressed populations of humans all over the planet. Africa particularly, where famine, lack of clean water and sanitation are putting hundreds of millions of people under duress, has already seen epidemics of the ebola virus wipe out large numbers of people. Thus far, the scourge of Ebola has been contained through the heroic efforts of health workers, who risked their own lives to stem the disease’s lethal tide.
Ebiola is a highly contagious virus. Most people, who are afflicted, die horrible deaths from it, including health workers, who treat Ebola patients. The only redeeming characteristic of Ebola is that you can only be infected by direct contact with an Ebola patient or with that patient’s bodily fluids.
What would happen if a disease like Ebola mutated so that it could be carried in the air, so that direct contact could no longer limit the circle of infection. It’s a terrible prospect, but one that is very real. It’s an absolute nightmare to think about, but the chances of a pandemic of disease are substantilely increased by the relentless way humans stress our Earth’s living biosphere.
Here is an article on this subject that just appeared on the Washington Post.