This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
I should warn you. This is not going to be fun. But if you do read through to the end you may come away with a greater sense of control and perhaps, just perhaps, optimism in these unsettling times.
The not fun part is all about stepping back to examine the current state of human existence in a larger context. It’s not the ultimate context though. That particular grim horizon looms from a cosmic narrative telling us that Earth’s chances of a life-sustaining surface environment beyond more than the next billion years are slim (thanks to a steadily brightening sun and atmospheric water reaching the stratosphere and cranking up the greenhouse effect). And, of course, that narrative also tells us that eventually the Sun will get messed up, and that the entire universe will likely propel itself to a state of dismal lukewarm uselessness many, many trillions of years from now. That long future is not a place to look forward to, but it’s also not our problem.
No, for us there’s a more immediate existential challenge. That is the accumulating evidence that we live within an extinction event. In fact, because we’re such winners we may actually live within a mass extinction event. That extinction, variously labeled as the Holocene extinction or the Anthropocene extinction, is proposed because of the shocking rate of disappearance of known species happening right before our eyes, as well as across the not-so-distant past.
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Remember, before 10,000 years ago there used to be some serious megafauna on every continent. From mammoths to giant marsupials. More recently there were as many as 60 million buffalo in North America (a number that had dropped to literally a few hundred by the late 1880s). And megafauna represent just one category of the species that have gone away in the past several thousand years. Today it’s estimated that species are ending their runs at rates as high as 1,000 times the ‘background’ rate in non-extinction periods.
That an extinction of this magnitude may be occurring is not, by itself, so strange. Life on Earth has experienced as many as two dozen sizable extinction events, among which have been five that qualify as ‘mass’ extinctions: Episodes wiping out more than 75% of species. Of course, individual extinctions are literally happening all the time as species reach the end of their little twigs on the tree of life. That relentless pruning isn’t a flaw in Darwinian evolution, it’s a critical feature that ensures the continuation of a lineage of living things reaching back billions of years. Indeed, of the four billion or so distinct species estimated to have ever emerged on Earth, 99% have also disappeared.
What may distinguish the current situation is that it appears directly correlated with purposeful human activity. From the destruction of native habitats to the general pollution and degradation of environments. To fundamental changes in climate zones and weather patterns that wreak havoc on established equilibria in species behavior and population dynamics. In other words, this may be the first time that a cognitively sophisticated (purportedly) species allows its behavior to fundamentally alter the history of life on the planet. Past instances, such as those connected to the possibility that methane-producing microbes dramatically perturbed Earth’s climate and chemistry were arguably ‘dumb’ extinctions. The tiny microbes were innocent slaughterers of others, little more to blame than asteroids or volcanoes.
That gets us to the real point here. Which is not about actually identifying the current culprit (yes, it’s us, just to confirm that), but is instead about reflecting on what it’s like to live inside a mass extinction event.
Let’s take the past century or so and look at some of the ‘big things’ that have happened to our species. We have, of course, had some massive wars. We’ve also had other kinds of massive humanitarian disasters. From dust bowls and crop failures to famines. Sweeping diseases, from influenza to persistent malaria, to HIV and AIDS, to the current novel coronavirus. We’ve also seen more stealthy afflictions. Nutritional problems and morbidities due – somewhat ironically – to our skill at producing long-lasting, sterile food that keeps us sated but woefully damaged in terms of what our bodies really need. From Twinkies to sugary soda and processed meats. Cardiovascular problems, diabetes, cancer, all seem to be exacerbated by many of the ways we’ve found to seek sensory comfort or to profit off of each other. Whether via food or drugs.
We’ve also placed ourselves in polluted environments, and filled the world with things like microplastics and abnormal pulses of radioactivity. Even our noble efforts to fend off bacterial pathogens are selecting ever more devastating microbes to have their way with our tender cells.
And here’s the thing. This all fits really nicely with the scene inside an ongoing extinction. The pruning of the tree of life doesn’t happen overnight. It involves the degradation and erosion of systems and equilibria that might otherwise have been maintained for a long time. It’s a seeping, gnawing erosion of success. There is rot, and the rot spreads until life is pruned away.
But for us it’s not just these tangible, physical things that are indicators of a downslide. It’s also how we cope with the world, how we either contain problems or spiral out of control. The present global pandemic of COVID-19 is a pretty good example. We’ve shut much of our world down. And, as much as this is entirely rational, it also feels like we’re deer in the headlights, blinking a little stupidly. Sure, we’ll likely figure out solutions, either in vaccines or therapies, and through some social reconfiguring. But the extraordinary speed and scale with which our global civilization has crumpled to a messy heap may be precisely the kind of thing that happens when you’re already inside an extinction event. Stuff goes wrong. Horribly wrong. It keeps going wrong until one day there is nothing left to go wrong. That is, in essence, what extinction means.
The fact that our global civilization lives well beyond its means (on average) in an unsustainable fashion is another indicator. We’ve stretched things thin, and not equitably - even within our own species. With startling inefficiencies and bottlenecks in energy and food supply and distribution. Bad move. This is a further factor in actually increasing our vulnerability to the unexpected; on top of the flaws in our management of ecosystem, health, and resources. We have virtually no contingency plans or resources to draw on because we’ve been so busy maxing out our planetary credit card in a race against each other.
You may be wondering, if you remember how I started this piece, where the sense of control and optimism is to be found in all of this?
I think it’s in the following. No other species, to our knowledge, has ever had the capacity to decode the history of life and see the evidence of past extinctions. Nor has any other species had the capacity to recognize that it may be living within a major extinction event. That is a big deal. There is no rule book that says what happens if, in the middle of global extinction, a species emerges that tries to do something about it. In other words, there is no reason to imagine that it can’t be changed, or at very least diminished. In that sense we are extraordinarily lucky.
It will take some very grown-up behavior to not squander that luck. But the good news is that the way to a safe landing is not that hard to see. We know what it entails. It’s about being smart, being efficient, being generous with each other, and being sensible about treating the planet around us as a special and vital resource. We don’t have to turn back the clock. With enough commitment we can have our beer, chips, electric pickup trucks, and a habitable world too.
Happy, belated, Earth Day 2020.