The Call of the Rewild

Seventeen thousand years ago, Stone Age artists painted numerous beautiful pictures on rock walls of wild, cattle-like creatures called aurochs, indicating they must have been very important to the lives of our ancestors. Although these paintings have been preserved in the sterile environments of the now famous Lascaux caves in France, the aurochs were not so lucky. Partly domesticated nine thousand years later during the Agricultural Revolution, the rest of the aurochs were driven to extinction by the end of the Middle Ages. Now, however, as detailed in an April 4 Washington Post article, a nonprofit group in the Netherlands is trying to bring these aurochs back into our lives. Why are they doing this? How can such an ancient call still speak to us? And is it something we ought to listen to?

Unfortunately, this kind of disappearance from history by the aurochs is common. We may be in the middle of a sixth large extinction event, which prompted environmental scientists in 2009 to list biodiversity loss as one of the nine “planetary boundaries” that should be monitored for an overall picture of ecological stability. While it’s true there have been minor fluctuations in the environment since the last Ice Age, the relative stability during our current era compared to the rest of geologic history is what has allowed agriculture to develop and form the foundation of our complex and modern societies. Scientists believe that crossing one or more of the nine planetary boundaries may be globally disastrous due to the risk of triggering the kind of geologically sudden environmental change that most biological organisms cannot adapt to quickly enough to survive over the long term.

Frighteningly, we have already crossed three of the nine planetary boundaries and may only believe we’re okay because of the short-term focus of our evolutionary vision. In addition to crossing the prescribed boundaries for carbon in the atmosphere, and for nitrogen extracted from the atmosphere, we have also crossed the boundary for biodiversity loss. Prior to the Industrial Revolution, the extinction rate of species lost per million of total species-years (E/MSY) has been estimated to be between 0.1 and 1. Scientists setting the criterion for this planetary boundary decided the “safe” limit of extinction was 10 E/MSY, but currently, driven by human activity, the value is over 100. In other words, the current rate of extinctions on this planet is 100 to 1,000 times greater than it was before humans evolved, and that’s over ten times worse than what our best estimates think the planet’s currently supportive ecosystems can handle. This needs to change. Or, as Aldo Leopold wrote in his 1924 essay, “The River of the Mother God,”

It seems to me we fail in the ultimate test of our vaunted superiority—the self-control of our environment. We fall back into the biological category of the potato bug which exterminated the potato, and thereby exterminated itself.

Protecting wild landscapes through the creation of national parks has been called “America’s best idea” by documentarian Ken Burns. But what if we hit upon that idea too late? Philosopher and endangered species biologist Winthrop Staples says in a paper that: “The great weakness of the present operative environmental ethics is its imprecise nature, which continues to allow what Aldo Leopold called ‘museum piece’ preservation of small nature reserves incapable of supporting large enough species populations to insure their long-term survival.”

To address this weakness, the concept of “rewilding” has been introduced. The term first occurred in print in 1990 and is used to describe large-scale conservation efforts aimed at restoring and protecting natural processes and core wilderness areas, making connections between such areas, and protecting or reintroducing apex predators and keystone species. Just like the aurochs.

There have already been many examples of rewilding projects around the world: the American Prairie Foundation reintroducing bison to the grasslands of the Great Plains in the hopes of creating a preserve bigger than Yellowstone Park; the European Green Belt built along the former Iron Curtain; the Gondwana Link, which aims to regrow native bushland in Australia; the attempt in South Africa to recreate the quagga, an extinct subspecies of zebra; and the Área de Conservación Guanacaste’s restoration of dry tropical forest and rainforest in Costa Rica.

Perhaps the best example of the benefits of rewilding, however, is captured in a four-minute viral video “How Wolves Change Rivers,” produced by the Sustainable Man group. The video explains the widespread impact that the introduction of wolves had on Yellowstone National Park through a process named recently by ecologists as “trophic cascades.” These are changes at the top of food chains that tumble down through the rest of the ecosystem. In the video, we learn that wolves do kill, but they also give life to many others.

For seventy years, there were no wolves in Yellowstone, so the various deer and elk populations exploded, resulting in them eating all the vegetation in the park down to very low levels. Once the wolves returned, they ate some of these grazers. More importantly, they radically changed their behavior, chasing them off many locations in the bare valleys where the wolves could easily hunt them. In just six years, the average height of trees in some areas quintupled. Then came lots of birds, and beavers too, creating even more niches for otters, muskrats, ducks, fish, reptiles, and amphibians. The wolves also killed coyotes, so rabbits and mice grew in number. That led to more hawks, weasels, foxes, and badgers. Ravens and bald eagles were among the carrion eaters who found more food in this richer environment. Bears benefitted from this too, finding more berries as the vegetation thickened, and they reinforced the impact of the wolves by also killing some young deer. All of this even changed the behavior of the rivers. The regenerating forests stabilized riverbanks, so they collapsed less often. The rivers moved around less, there was less erosion. The channels narrowed, pools formed, and there were more riffle sections. All of this proved better for wildlife. Wolves, though small in number, changed everything, including the physical geography. That’s rewilding.

Now, following on the heels of these successful demonstrations, the idea is reaching the mainstream and about to get much more notice. In March two-time Pulitzer Prize winner E.O. Wilson released Half Earth: Our Planet’s Fight for Life, the final book of his worldview-defining trilogy. According to the promotional material for Half Earth, Wilson argues that, “In order to stave off the mass extinction of species, including our own, we must move swiftly to preserve the biodiversity of our planet….Half Earth argues that the situation facing us is too large to be solved piecemeal and proposes a solution commensurate with the magnitude of the problem: dedicate fully half the surface of the Earth to nature.”

Why half? I’ll have to read the book before I can answer that, but Wilson hinted at it in his 2002 book, The Future of Life. The argument is summed up nicely in the paper by Staples mentioned earlier.

Within regional areas, humans have heavily modified or destroyed all or most of the most economically profitable ecosystems, thus leaving wildlife to struggle for existence on areas heavily biased toward “rock and ice”….Currently, approximately 10 percent of land areas are in protected status, but according to the area species principle this assumed 90 percent destruction of habitats means that approximately 50 percent of existing species will eventually become extinct….When the [species area relation] calculation is performed for 50 percent [preservation], the results suggest an approximate loss of 15 percent of the original species or a retention of approximately 85 percent. This is a vastly better state of affairs than the status quo.

In light of this larger vision of rewilding, bringing the aurochs from Lascaux’s cave paintings back into our lives is an inspiring project. To be sure, there are questions about its details that remain open for exploration, but there is no doubt it is the kind of experiment we should be trying as we search for survival solutions. As a philosopher and writer, I spend a lot of time considering the power of essays to affect our reason, and the power of art to affect our emotions. Often, these are considered separate aspects of humanity, but really these are two sides of the same coin. The philosopher David Hume told us reason is the slave of the passions, but the modern science of psychology shows us that emotions arise after cognitive appraisals. Thus, there is a bi-directional feedback between the two. The best rational arguments move us emotionally, and the best emotional art has a rational message behind it. I find it almost incredulous that the simple artistry of animal sketches can inspire such powerful reason and emotion, that they can have such lasting effectiveness and importance to our lives over many millennia. But really, it’s not incredulous. It’s just wild.