We just had Earth Day, with people all over the world turning out to proclaim their reverence for the Earth and their intention to protect it — from us.
There is no question that human activity is harming the Earth’s natural systems, threatening entire ecosystems and the extinction of many species. But we depend on those natural systems and those other species for our own survival. So we need to protect them for our own benefit, as much as anything else.
Happily, no matter what we do, the Earth itself doesn’t need saving. It is 4.5 billion years old, has survived asteroid strikes and much else, and will be here long after we are gone — although it will be destroyed about 7 or 8 billion years from now when the Sun balloons into a red giant.
Life on Earth is almost as old as the planet; the first cells started to form about 3.8 billion years ago. As far as we know, we are the only place in the universe where life exists, although if it exists elsewhere, it is likely not a very common occurrence. So given its presumed rarity, we have a profound ethical responsibility to preserve life on Earth.
Like the planet, life is resilient. There have been five “Great Extinctions,” and in the most serious of these, the Permian-Triassic extinction event 252 million years ago, about 90 to 95 per cent of all species were wiped out. The most recent one, triggered by an asteroid strike 65 million years ago, wiped out about 75 per cent of all species, including the dinosaurs. But life continued.
So almost certainly life will continue after the Sixth Great Extinction — the one we are causing right now. But while life overall might survive, many of the species we love and cherish — and far more species that might not be so lovable but upon which we depend — might not survive us.
One species to which we are greatly attached — homo sapiens, us — also might not survive, an occurrence for which the rest of life on Earth might give a collective sigh of relief. But while we are not immune to extinction, I doubt if even homo sapiens needs to be saved.
We are after all “a weedy species,” as Elizabeth Kolbert called us in her 2014 book The Sixth Great Extinction, like cockroaches and rats, only more so. We can live pretty much anywhere, we breed like — well, humans — and, much more troubling, we can bend and shape our environment to our own ends.
So the chances are that humans will survive, although potentially in much smaller numbers, and perhaps driven back to a more basic way of life. Jared Diamond explored this idea 20 years ago in his book Collapse, pointing to several examples of civilizations that have collapsed at least in part due to ecological changes.
What might need saving — if indeed it is worth saving — is our current “civilization” — and I use the term advisedly. A “civilization” that is radically altering the Earth, creating a mass extinction and undermining the basis for its own survival can hardly be called civilized. But on the other hand, the world’s civilizations have created great beauty, great thinkers, great scientific advances, massive increases in life expectancy and the quality of life for many — so there are some aspects worth saving.
Which brings us to “planetary health,” a concept created a few years ago by Richard Horton, the editor of The Lancet, one of the world’s leading medical journals. In the report of the Rockefeller Foundation-Lancet Commission on Planetary Health, it was defined as “the health of human civilization and the state of the natural systems on which it depends.”
So I applaud all who come out on Earth Day to protect the Earth. But as they well know, the present dominant global civilization is not healthy for the planet and thus not for us. Protecting life on Earth, including our own species, requires a radical transformation of society, a new way of relating to the Earth, its many species and each other, a planet-wide civilizational shift. This is perhaps the ultimate point of Earth Day — to save us from ourselves.
Dr. Trevor Hancock is a professor and senior scholar at the University of Victoria’s school of public health and social policy. His column will resume in June.