Friday, March 25, 2016

Half-Earth: Our Planet's Fight for Life

I've finished reading this latest work from E.O. Wilson, and though as expected I agree with him on just about everything, I found the book a little tiresome despite its brevity. The main idea is relatively straightforward: biodiversity is shrinking, and as a precaution we ought to set aside half the planet as a protected wilderness:
For the first time in history a conviction has developed among those who can actually think more than a decade ahead that we are playing a global endgame. Humanity's grasp on the planet is not growing strong. It is growing weaker. Our population is growing too large for safety and comfort. Fresh water is growing short, the atmosphere and the seas are increasingly polluted as a result of what has transpired on the land. The climate is changing in ways unfavorable to life, except for microbes, jellyfish, and fungi. For many species it is already fatal.
Among the facts he presents, we have identified only two million out of the estimated eight million species on Earth, and the rate of extinction is currently estimated at 877 times higher than what it was before humans came along. Wilson's primary argument is that biodiversity stabilizes the environment and that we don't know what will happen to us if the current wave of mass extinctions continues; if half the Earth is protected, that should be enough to preserve at least 80 percent of the existing species.

I interpret Wilson's position as an update of the warnings made by Thomas Malthus two hundred years ago. Essentially he is saying that our species may become extinct because overpopulation may make it impossible to sustain ourselves, and he is adding that our destruction of the environment is creating an even larger challenge than the prospect of running out of food. The shortcoming of the book is that it meanders over this turf without sticking to a controlled argument and leaves the reader distracted by an accumulation of superfluous information. Much of the information is interesting in its own right, but its presentation detracts from the pointed subject matter summed up by the title. Half-Earth is getting little attention in the press, and if Wilson wasn't marginalized already as a thinker, he is clearly becoming so now. At 86, and having suffered a stroke, it is remarkable that he has the stamina to continue working at this pace – this is his thirty-second popular book – but you have to question his efficacy at this point.

Like many of Wilson's books, portions of the text are devoted to descriptions of unusual organisms, and in this instance they don't particularly support his argument. He also describes in detail regions of the world that would be suitable for preservation as wilderness. He often inserts personal anecdotes about his experiences in the wild. These parts of the book seem more like recruiting tools to attract people to his profession, because he is keenly aware that true naturalists like him are becoming a rarity. The jobs now available to young biologists are far more specialized than they used to be, and it seems unlikely that future generations will produce generalists like him.

Wilson is somewhat more effective when he describes just how destructive humans have been to ecosystems. This is particularly true of isolated islands:
Hawaii, universally acknowledged as the extinction capital of the world, had the most to lose when the Polynesian voyagers first came ashore, and with the later help of Europeans and Asian colonists, they extinguished most of its native bird species. Gone are the native eagle, a flightless ibis, a ground species the size of a turkey, and more than twenty species of drepanidid honeycreepers, the latter small pollen feeders, many with brilliantly colored plumage and long curved bills that probe deeply into tube-petaled flowers. And many more – in excess of forty-five species – vanished following the arrival of the Polynesians before A.D. 1000, and twenty-five followed the entry of the first Europeans and Asians two centuries ago. Oddly, the feathery remains of some of the most colorful extinct species are preserved in the cloaks of the old Hawaiian royalty. 
He devotes too little space to countering the arguments for "new conservation" put forth by "Anthropocene enthusiasts" such as Erle Ellis, who says: "Stop trying to save the planet. Nature is gone. You are living on a used planet. If this bothers you, get over it. We now live in the Anthropocene – a geological epoch in which the Earth's atmosphere, lithosphere, and biosphere are shaped primarily by human forces." Wilson's refutation of this position is muted and haphazardly scattered throughout the book. His main argument, as far as I can make one out, is that ecosystems are complex beyond our current comprehension, that we don't know how most of them operate, and that it is sheer unfounded arrogance to state that we can somehow "manage" the environment to ensure human survival in the future.

He does get in a few jabs at scientists and environmentalists who embrace "Anthropocene ideology." He aptly compares some of them to contemporary economists who use complex mathematical models to explain economic behavior. I didn't think that he exploited this criticism enough, because it has been apparent in recent years that even the most sophisticated economic models produced by leading economists have been of little value for macroeconomic forecasting. Economics, insofar as it is a science, attempts to predict certain aggregate behaviors of one species; if it is doesn't work for one species, who would expect that, using similar techniques, conservationists would be able to predict the behaviors of millions of species, most of which haven't even been discovered yet? When it comes to the world's ecosystems, we have only the flimsiest understanding of them. The argument that humans are incapable of managing all of the living organisms on the planet in order to produce the outcomes we want is pretty much a no-brainer, and Wilson would have been more effective if he had devoted more space to that. In reading the book, one repeatedly senses his outrage at technological arrogance and the shortsightedness of capitalism, but many of his readers won't come away from it feeling that he has succeeded.

Because my worldview was already quite similar to that of Wilson, I am still able to see his proposal as a bold one that should be given credence. However, as it stands, the book is likely to be "shelved" literally and figuratively. I can only speculate that he was attempting to pull his punches a little so as to gain acceptance from a wide audience. In particular, he must be wary at this stage in his career of offending the large number of people who never warmed up to his ideas about sociobiology. Unfortunately, in America, that group still includes a majority of the public, as well as a majority in business, politics and academia. Whatever his weaknesses, Wilson is a truly courageous thinker whose ideas are definitely worth considering.

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