The Witness

Opening our eyes to the nature of this earth.

| Fall 2015

The greatest ecological crisis in the earth’s history began with the emission of climate-changing gases by an organism that had spread widely across the planet, colonizing many of its ecological niches. These gases—the waste products of its lifestyle—gradually accumulated in the atmosphere. For a long time nothing noticeably changed, but at some stage a tipping point was reached and the planet’s climate flipped rapidly from one state to another. The composition of the atmosphere changed, becoming poisonous to most life on earth, and the planet’s mean temperature plunged, precipitating a global ice age. The resulting mass extinction killed perhaps 90 percent of all living things on earth.

This was 2.3 billion years ago. The climate-changing organisms were bacteria, and the poisonous gas they emitted was oxygen. Without the planetary catastrophe they precipitated, you, and almost everything you know about life on earth, would never have come about at all.

All told, there have so far been at least five, and perhaps as many as twenty, “mass extinction events” in the history of earth. This first one—known as the “great oxygen catastrophe”—was the most far-reaching. The last, 66 million years ago, is the one we know best, because it is the most appealing to the human imagination: It wiped out the dinosaurs. Overall, it is estimated that around 98 percent of all organisms that have ever existed are now gone forever.

All created things perish, said Gautama Buddha. Whatever is subject to origination is subject to cessation. This, it turns out, is true of an individual, a species, an ecosystem, or a planetary epoch. Whatever the Buddha saw under the Bodhi tree—whatever it was that showed him the ceaselessly changing nature of all things, and convinced him of the misery caused by attempting to cling to temporary states of apparent stability—has been more than borne out by consequent studies of the earth’s geology, ecology, and biology. The nature of this earth is change. The nature of this earth is endings. The nature of this earth is extinction.


As you read this, the earth is currently experiencing the latest extinction event in its 4.6-billion-year history. This one, known as the Holocene Extinction, is being caused not by cyanobacteria or asteroid impacts, but by human beings. Arguably, it has been going on for at least 10,000 years, since the extinctions of the great megafauna—the mammoths, the ground sloths, the sabre-toothed cats—who in all likelihood were pushed over the brink by human hunters. But it has accelerated greatly since the Industrial Revolution and has gone into overdrive in the last half century. The current extinction rate is estimated at anything between 100 and 10,000 times the expected rate of “background extinction,” and as the expansion of the human economy continues, with its associated resource extraction, fossil fuel combustion, population increase, and mass destruction of ecosystems, the Holocene Extinction is accelerating beyond our ability to even accurately measure it, let alone put any kind of brake on its progress.

1/13/2016 10:58:28 PM

I enjoyed reading this article. The author has integrated his personal journey with spiritual and ecological perspective in a way that touches both head and the heart. Koodos