To Be or Not to Be: That Remains the Question

Iremember clearly when, at age 13 or so, as the Cold War was heating up and nuclear bombing threatened, my classmates and I were marched out of the classroom, lined up sitting in the corridor, and told to put our heads between our legs (and, we added, kiss our asses goodbye). I do not recall being as terrified by world events since that time, but if Barnosky and his ilk are correct, I should be, and Dodging Extinction probably has as good a list of things to be terrified about as any. The book is well written, well referenced, and scientifically explained by someone with excellent credentials. However, the items on his list will be no news to most, and the likelihood of these events in the future (he gives two centuries)—or their elimination by human actions—remains elusive to me.

As a paleontologist, Barnosky contemplates the Earth's five preceding mass extinctions. He considers both asteroids and huge volcanic eruptions, eventually concluding that each was preceded by at least two of the following: carbon dioxide (CO₂) increases, ocean acidification, climatic warming, and oceanic anoxic areas. Since the present situation has those same four symptoms, he opines, “All past mass extinctions seem to have involved two of these four factors, and we've got all four of these things not only going on today but actually accelerating; what does that say about the plausibility of another mass extinction?” (p. 48). Thus, Barnosky finds compelling evidence for the inception of a sixth mass extinction, driven by humans, with already about 30 percent of Earth's species threatened: “As our numbers grow, spreading like ravenous army ants, a perfect storm of impacts spreads across the Earth.” He finds considerable evidence that what humans are doing is mimicking the conditions that generated past mass extinctions.

Barnosky characterizes himself as an optimist, a realist, and a paleontologist. His optimism prevents him from giving up hope, despite the tremendous marshaling of scary evidence. As a realist, he traces the environmental onslaught to food, energy, and money, doubting that humans will give up those chases any time soon. It is the paleontologist role that I found most interesting. Barnosky is a great storyteller, and his best stories were fun summaries of uncovering various paleontological events.

The book's first two chapters make the case for the existence and importance of “the species extinction storm.” In “The last ones standing,” Barnosky summarizes the information on a number of species facing extinction (e.g., lonesome George, recently the oldest Galapagos turtle, where there had been no reproduction for more than 100 years because of feral predators). He provides lots of data suggesting extinction rates are worsening. In “It's not too late,” Barnosky gives examples of useful human interventions. For my own example, one of my colleagues shot hundreds of wild goats, eliminating them from several Galapagos Islands, and now reports that the turtles are reproducing.

The second section provides the drivers of species extinction, which come together in a “perfect storm” of impact. Barnosky's most important mechanism for extinction is habitat reduction from conversion of natural lands into agriculture. He recommends closing the “yield gap” by increasing agricultural efficiency, eating less meat, and decreasing waste.

Barnosky thinks energy is especially important, as do I, but emphasizes much more the negative side effects than the critical role that energy plays—and will continue to play—in supporting whatever humans do. Although Barnosky admits that he likes modern conveniences, he concludes that we need to replace ­fossil fuels. He argues—naively, in my ­opinion—that we can replace fossil fuels with biofuels (most of which have little or no net yield), efficiency, and solar power.

Barnosky's ultimate solution, always just beyond our fingertips, is solar energy. In his mind, it seems easy, given that solar input is nearly 4 million exajoules per year, versus only 550 exajoules from all fossil fuel burned to date. The rub is capturing it, for most solar technologies have a rather low energy return on energy investment compared with those of fossil fuels. And even according to Barnosky's own calculations, reducing our energy use to anything that might be sustainable would be a big sacrifice for most Western people.

The food chapter argues that demand for food (especially meat) destroys habitat. Barnosky discusses how we might become more efficient and less harmful in our production of food, removing less land from natural systems and wasting less energy. Although Barnosky does mention human population growth, I was surprised that he did not give it much more attention.

The chapter on money was strange to me. Barnosky repeats estimates of the dollar value ($31 trillion) of ecosystem services, and he gives good examples of where those services have protected land (e.g., in the Yangtze watershed). He also gives existing values for CO₂ emissions (roughly $50 per ton of carbon) that he thinks should be added to fossil fuel costs. This got me thinking about cost–benefit analysis, because this is only the costs. Assuming that about two-thirds the world's $80-trillion gross domestic product is attributable to burning fossil fuels (Hall and Klitgaard 2012), the economic gain from burning fossil fuels is about $5300 per ton of CO₂ produced—100 times more than the cost (derived by dividing-two thirds of global GDP by total carbon release). No wonder we have such a hard time moving off fossil fuels; they are too valuable in generating wealth. Of course, we “need” to abandon fossil fuels to protect the climate, and maybe we can generate an equal amount of wealth from noncarbon fuels, but I for one shall not hold my breath. Barnosky ends by observing, “The open question of course is whether these nascent realizations will lead to a paradigm shift in how people think about making and spending money,” with which I certainly agree.

The book's final chapter is “Back from the brink.” In it, Barnosky begins, “Here's the catch: What's bad for other species is also bad for us.” He then discusses political climate-change deniers but also corporations that are making good moves and gives a series of small things that individuals can do. I did not get the sense that we were doing too much stepping “back from the brink,” as the chapter title suggests.

Barnosky provides “no silver bullets but a series of shotgun pellets,” such as increased efficiency of fossil fuel use. Some of his suggestions certainly appear plausible. Unfortunately, Barnosky, being honest and thoughtful, manages to undermine most of the solutions he presents, and I had little trouble finding fault with the remaining ones. For example, he gives a painfully detailed elaboration of possible methods to improve automobile mileage but then later admits that such improvements are likely to be swamped by more cars.

Then there is a question of scale, which seems to apply to most other similar analyses. Whereas it might be possible to shoot all the goats or generate ecotourism revenue from an actual or virtual island, doing this on a regional or global scale seems impossible, for cultural and logistic reasons.

Even more damning, whatever optimistic scenario you might choose, you are likely to soon run into the biggie: Jevons paradox, in which the efficient use of a resource leads to greater consumption of it—not less. For example, Sweden is a country in which conservation is taken very seriously. A government commission brought together nutritionists and environmental scientists and came up with a nutritious and CO₂-sparing diet. Eva Alfredsson (2002) compared Swedes who promised to follow this diet with those who did not. She interviewed both groups frequently and calculated the CO₂ released by each group. She found that the environmentally conscious group did indeed generate less CO₂ and spent less money on food. Looks like win–win, right? But when she looked at total household budgets, she found that the environmentally conscious group spent their saved money in fuel-intensive ways, such as more distant vacations. This effect canceled, and in some cases more than cancelled, their dietary CO₂ savings. About the only environmental benefit was that the first group presumably felt better about their environmental footprint. Genuine energy savings requires a holistic analysis, not Panglossian hope.

What should we do, then, if we wish to conserve species? My good friend Werner is a wildlife biologist in South America. He moved there because it had the highest diversity of the animals he was most interested in. Interestingly, he drives a highly fuel-inefficient truck, for conservation reasons. After many decades of research and conservation efforts, he is very depressed by the state of the animals he studies. He figures that there is no hope until the oil runs out and all the things that humans do are less able to be done—in other words, let's get it over with while we still have some species left to work with. Can that be a better strategy? Maybe so.