I originally downloaded the audio version of Elizabeth Kolbert’s new book, The Sixth Extinction: An Unnatural History, to simply keep me awake during a long wintry drive across the southern part of Minnesota and through the heart of Iowa. But by the time I arrived at my destination—a national conference on cover crops and soil health in Omaha—I realized Kolbert’s message was all too relevant to what I was experiencing on this road trip: mile-after- mile of formerly diverse prairie now sitting idle until spring, when it will be planted to corn or soybeans, which will grow a few months before being removed, leaving the soil impoverished above and below ground.
The loss of the prairie, considered the most substantial decline of any major ecosystem in North America, is what Kolbert would call a sign of humans imposing major alterations to the planet at an unprecedented rate. And it’s one of the drivers of a “mass extinction” that we are in the midst of, a catastrophic event that threatens to eliminate 20 to 50 percent of all living species on Earth by the end of this century. Mass extinctions are nothing new: scientists think the planet has experienced five such events during the past 3.8 billion years. The last one was caused by a miles-wide asteroid smacking into the earth and sending so much debris into the atmosphere that the entire climate was turned upside down, rubbing out the dinosaurs, among other species.
And that’s the point made by the many scientists Kolbert interviews and spends time with for her book: change is inevitable, but what makes mass extinctions so devastating is the rate at which change occurs, eliminating the opportunity for plants and animals to utilize the basic rules of evolution to adapt. But it doesn’t always take an asteroid or a volcano to bring about such sudden, devastating shifts. Sometimes it just takes “one weedy species” that has the ability to not only outright kill, but also to modify everything from the climate to the content of the very water, air and soil we depend on. We are that weedy species. Neanderthals lived in what is now Europe for 100,000 years and left no more impact on the planet than any other large vertebrate. Now consider the impact Homo Sapiens have had in just the past two centuries alone. Humans so dominate the earth today that some scientists have suggested we rename the current Holocene (from the Greek for “entirely recent”) era the “Homogenocene era.”
The author travels the world to see firsthand the impacts we are having on everything from amphibians and birds to coral reefs and forest systems. She combines firsthand accounts with references to the latest science to paint a fascinating picture of the world that’s been, the world that is, and the world that will be (if things don’t change fast). Kolbert’s clear, descriptive writing style makes a mountain of what could be overwhelming information quite digestible—although I’ll admit a lot slipped by me in the audio version while I was trying to navigate through ground blizzards.
And what all that evidence points to is one inevitable conclusion: our drive for ever more food, energy and space is making the world simpler, and thus less resilient.
It’s not all bad news. Kolbert acknowledges that there are numerous examples of humans trying to turn the hands back on the extinction clock. She describes a “frozen zoo” where cell lines of threatened species are stored in liquid nitrogen. Such efforts are an important acknowledgement that we’ve messed up and we are somehow responsible for fixing things. But they do not take into account the even bigger issue at hand: true mass extinctions don’t just weed out the weak and unprepared, they wipe out everything. Kolbert cites example-after-example from the geologic record of species that were quite well adapted to their environment, but were caught off guard when that environment changed dramatically.
“Among the many lessons to emerge from the geological record, perhaps the most sobering is that in life, as in mutual funds, past performance is no guarantee of future results,” Kolbert writes.
In other words, we aren’t just the agents of this mass extinction—we may also be one of its casualties. For example, our takeover of the nitrogen cycle and destruction of the plant diversity that keeps our soil healthy is starting to show signs of threatening our very ability to produce food, particularly in an era of unpredictable climate events.
I thought about that during the soil conference in Omaha, where farmers, scientists and conservation experts discussed ways of bringing resiliency back to the land. Kolbert would have seen this conference as an example of humans seeing the writing on the wall—unprecedented erosion events, the Gulf of Mexico dead zone, superpests, unexpected crop failures—and attempting to take steps to head off disaster.
But are such discussions just another example of people trying to prove we have the ingenuity needed to survive a little longer, or are they rooted in the acknowledgement of a basic truth: developing solutions that fix isolated, immediate problems don’t matter in the big scheme of things if they end up limiting long-term resiliency? No other species has the ability to decide what evolutionary paths remain open, and which are closed.
Asks Kolbert, “Isn’t the whole point of peering into the future so that, seeing dangers ahead, we can change course to avoid them?”
Brian DeVore is the editor of the Land Stewardship Letter.