Dodging Extinction: Power, Food, Money, and the Future of Life on Earthby Anthony D. BarnoskyUniversity of California Press, 2014 Anthony Barnosky is a professor in the Department of Integrative Biology, Curator in the Museum of Paleontology, and Research Paleontologist in the Museum of Verterbrate Zoology at the University of California, and his new book, Dodging Extinction, comes with a cover blurb by Elizabeth Kolbert, author of The Sixth Extinction: "When a paleontologist warns that something very unusual in Earth's history is taking place right now, everyone ought to pay attention." The weight of the blurb comes not from the professional emphasis, of course, but rather from the fact that Kolbert herself issued the same warning in her enormously successful book The Sixth Extinction. Kolbert is a journalist, and her book is a stunning tour de force of science reporting but not a particularly optimistic thing; she makes it fairly clear that the latest Mass Extinction to face our planet has already started and cannot be stopped, any more than could the Mass Extinction 66 million years ago that wiped out the dinosaurs, or the one 252 million years ago that wiped out over 90 percent of all life on Earth.Barnosky is a good deal more upbeat. No matter the dire tidings he relates, he almost always chases them with some variation of "There are rays of hope" - even though he paints the same pictures as Kolbert does, with the same vivid prose:

We know that about eight hundred species have died out in the last five hundred years. We also know that the vast majority of those species were driven to extinction by people - because we overhunted them, converted their natural habitat into something that we thought would serve us better in the short term, or introduced competing species intentionally or inadvertently. Those are, of course, the sam threats that are driving species toward extinction today, although the magnitude of those threats has increased dramatically, and some new ones (like pollution and climate change) have been added. Continuing the present rates of decline means that all of those 20,614 currently threatened species will be extinct within the next five hundred years (many of them much, much sooner). That would be twenty-five times as much loss in the next five centuries as in the last five.

He talks to environmentalists and other specialists in the course of his book, and he goes into the field to examine the state of things for himself. He has a wonderful way of presenting both himself and his material; he's accessible without ever simplifying. It's a knack too few science writers since Carl Sagan have had, and it will make his readers envy his students.But not all the rhetorical skill in the world can change the black nature of the facts. There are roughly 8.7 million species of macroscopic life on Earth, and there's hardly even one of those species that isn't affected, strained, or outright threatened by the mind-boggling rapaciousness of humans. In addition to expanding into every natural habitat on the planet in unprecedented, unsustainable numbers, humans are also actively hunting and killing more kinds of life and in greater quantities than they ever have before - and this is before we factor in the catastrophic changes human technology is wreaking on the planet itself.Barnosky is clear-eyed about all of this:

Now, you have to ask yourself: If the worst mass extinctions of all resulted from the cascading effects of rising CO2, climatic warming, ocean acidification, and dead zones and all past mass extinctions seem to have involved at least two of those four factors, and we've got all four of those things not only going on today, but actually accelerating - what does that mean for the plausibility of another mass extinction? Furthermore, what does it mean when we throw into the mix the two other major ways that humans are affecting other species: taking over much of Earth's surface for our own needs, and relentlessly killing other species and destroying where they live for short-term economic gains?

"What it means," he concludes, "is that there is no doubt we are now brewing up the perfect storm to trigger the Sixth Mass Extinction."And yet, he persists in striking a hopeful note. He reverts again and again to the ingenuity of mankind, its resourcefulness once it wakes up to looming crises, and he's clearly hoping his optimism will inspire his readers to seek out ways they themselves can help avert the Sixth Extinction. Unfortunately, almost all of the potential counter-measures he describes range from the dauntingly unlikely to the downright delusional (he spends a good deal of time, for instance, on "Revive and Restore," the crackpot project begun by Stewart Brand and Ryan Phelan to bring back the passenger pigeon).However readers react to Barnosky's optimism, he's certainly sounded the cheeriest Trump of Doom yet recorded. But when he talked about these conservation issues with his students, one of them gave back a line that's worth an entire book in its flat inexorability: "If it comes down to between keeping elephants alive and people alive, elephants gotta go." From out the mouths of babes and undergrads.