I am not a scientist but can appreciate works like Peter Ward’s Under a Green Sky (2007) as a useful popularization by a new breed of paleontologist who integrates other sciences into the search for patterns or cycles of mass extinctions on Earth.
Up to recently, the consensus on the cause of the the most recent extinction (Cretaceous-Tertiary) was an asteroid strike, since nothing else could explain the sudden heating of Earth. Ward usefully documents all of the most recent evidence, ranging from rock cores in mountains to ocean oxygenation to measurements of carbon dioxide and hydrogen sulfide, all pointing to accelerating carbon dioxide and massive warming as a driver of extinction on Earth.
Though a scientific theme, the concept of mass extinction certainly has its philosophical implications. Extinction is another word for death on a massive scale, of species or of life in particular geographic regions. But war, genocide, exterminations, scorched earth policies, deforestation and the like have existed throughout human history, reflecting how human beings have changed their local “environment” long before the advent of higher technology. Environment in this sense is cultural and social, as well as a mental environment that is hidden away from consciousness as a belief, a fear, an obsessive drive.
But first we experience death as individuals. However much our necessary connections with a physical habitat or a culture, with a place or with loved ones, our death is an extinction, even if we hope others will remember us or keep our effects.
Reflecting upon death is a source of discovery because it reveals to us our solitude, a solitude which has always been the core of self but was muted over by the noise and distraction of society and people around us. We are born for extinction; we have been dying from the moment we were born.
The drive or instinct of a living Earth viewed as Gaia is to give life, prolifically, like the Mother or the Creator, the engendering, birthing and nurturing principles of the universe that go on with blind faith, with perseverance, with eternal hope. And yet all life, all extant things, while abiding in this primordial sea of being, contain the seeds of death, of the dissipation of time and the limits of space. These factors close in upon that single entity and rip it apart, body and soul. Nothing is more poignant than suffering except suffering as a process, a trajectory, towards death. We see it consciously, yet Gaia does not, nor does the Tao nor God, nor does anything step in to consider why this and not some other pattern should rule the universe.
There is no solace in the scientist’s assurance that we are all part of the matter, the same energy, originating in the core of a distant star — that our atoms and molecules, the stuff of our hearts and livers and brains, were forged in the furnace of a distant star abiding in a far-away galaxy. No, we want to live now, on this humble green earth, with the familiar trees and clouds and winds. No wonder that Emily Bronte cried out that she did not want Heaven when she died, for nothing could replace a single day on this Earth.
And now science blithely assures us that life on earth will be extinct not in a few million years (as scheduled) but that it will face mass extinction within decades if carbon dioxide continues to rise in the unforeseen proportions that it is rising. At this point in time it is a matter of numbers and optimistic folly. Some scientists say 400 parts per million is the tipping point, and others 350. But we are already at 385 ppm.
The sequence described by Ward, and by many scientists besides, foresees erratic weather patterns, increasing ocean dead zones, polar meltdown, ocean conveyor system shutdown, sea-level rise … and, ultimately, seas erupting excessive hydrogen sulfide mingling noxiously with a once blue heavens to leave us helplessly “under a green sky.” (blue + yellow = green).
Extinction is a hundreds of millions of years cycle. Or it is within the lifetime of many in the not-distant future who will be victims of social and climate change. Or it will be ourselves as individuals, irregardless.