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Apocalypse Then … Then & Then. One More for the Road?

Posted by Richard Conniff on July 10, 2017

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Artist’s conception of a major steroid impact

by Richard Conniff/Wall Street Journal

For everyone who loves disaster movies, and the sound of Wile E. Coyote going splat, here’s a book about Planet Earth’s multiple suicide attempts—sorry, mass-extinction events. The Earth “has nearly died five times over the past 500 million years,” notes science writer Peter Brannen in “The Ends of the World.” One of these events, the End-Permian Extinction 252 million years ago, killed more than 95% of all living things, earning it a reputation as “the Great Dying.” The other four, muddling along at a somewhat more modest rate, were nonetheless apocalyptic enough to make biblical floods and famines seem like Monday at the office.

Mr. Brannen sets out to learn “just how bad” it could get, with a view to understanding our own future as climate change advances across the planet. Brace yourself. It’s not just about “a rock larger than Mount Everest” slamming into the planet at a speed “twenty times faster than a bullet.”

That is of course the leading theory about what happened to Tyrannosaurus rex and friends in the best-known mass extinction, at the end of the Cretaceous Period 66 million years ago. Debate about this theory in the 1980s began in ridicule and progressed to widespread acceptance, with the fatal asteroid ultimately linked to an impact crater 110 miles wide on the coast of Mexico’s Yucatán Peninsula. An alternative—or possibly complementary—theory puts the blame on massive volcanic eruptions occurring almost simultaneously on the opposite side of the planet, in the Deccan Traps of India.

As a result of the debate over what killed the dinosaurs, the study of mass extinctions, “long pushed aside as a disreputable fringe of paleontology,” became cutting edge, Mr. Brannen writes, and it has opened up a whole new world of potential Armageddons. Thus he gleefully introduces readers to “truly mind-blowing cyclical floods called jökulhlaups,” waves “20,000 feet high,” catastrophic volcanic eruptions that make Krakatoa or Vesuvius look like “pathetic burps,” 500-mile-per-hour winds loaded with toxic hydrogen sulfide, and vast swaths of the planet alternately buried under miles of ice, baked at 140 degrees Fahrenheit or drowned by oceans like hot soup.

Palisades: The long view of catastrophe

The evidence of past extinctions turns out to be surprisingly visible all around us in North America. “We live on a palimpsest of earth history,” Mr. Brannen writes. Look west from Manhattan, for instance, and the high cliffs of the Hudson River Palisades are a vestige of the End-Triassic mass extinction 200 million years ago. They were formerly “gigantic underground channels” spewing an “incandescent fountain” of lava, much of which landed a little to the west, forming New Jersey’s Watchung Mountains.

West Texas, an arid region best known for its Permian Basin gas and oil fields, is similarly the perfect destination for End-Permian tourism. The Guadalupe Mountains there are a former barrier reef, a “marine tableau, frozen in limestone,” made up of what were once vase sponges, horn corals, crinoids and other ancient sea creatures, the last profusion of species before the Great Dying. “Life on earth,” Mr. Brannen reminds us, “constitutes a remarkably thin glaze of interesting chemistry on an otherwise unremarkable, cooling ball of stone.”

Mr. Brannen’s travels introduce us to the paleontologists who work these landscapes, often by studying the fossil remains of uncharismatic invertebrates. The paleontologists tend to “regard the dinosaur folks,” one of them admits, in the same slightly patronizing way that “marine biologists look at people who work with dolphins.” These visits are occasionally illuminating. We learn, for instance, that the continents did not always have our familiar north-south orientation. In the Ordovician Period roughly 450 million years ago, North America, Siberia, Australia and other continents drifted in isolation along the equator. So while many species in our time have already begun to extend their ranges north or south toward the poles, in response to the warming climate, their Ordovician counterparts “found themselves marooned on their island continents, separated from habitable refuges by vast open oceans.”

Unfortunately, Mr. Brannen’s travels often distract more than they inform. He spends much of the book bouncing down a dirt road to the site of some past geological catastrophe or other. But he seldom sticks around long enough to see much or to help readers understand what was happening, or why, in any given period. He works desperately to avoid being dragged down by humdrum details. “When a geologist calls something boring, reel in horror,” he advises. But his alternative is to reach for snappy-sounding descriptions—the ancient armored fish Bothriolepis and Dunkleosteus resemble “bony Frisbees” and “psychotic torpedo Cuisinarts,” respectively—that just leave the reader mystified.

Mr. Brannen is also obsessed with the apocalyptic tendencies of the present day. This is understandable, given our deadly mix of greenhouse-gas pollution, ocean acidification and species extinction. But past extinctions are complicated enough on their own. Competing theories about these ancient extinction events abound, and readers need an evenhanded guide to weed out the wild speculation from ideas more firmly grounded in evidence. Instead, Mr. Brannen repeatedly flashes forward, pausing, for instance, during a description of a catastrophe that happened 252 million years ago to interject: “No one knows where our modern experiment with the planet’s geochemistry will lead.”

If you want to understand past extinction events, you would do better to try paleontologist Norman MacLeod’s 2013 book “The Great Extinctions.” For the current world-wide disappearance of species, try Elizabeth Kolbert’s “The Sixth Extinction” (2014).

A Jurassic ammonite fossil on the beach in Dorset, England. Photo: Getty Images/Nature Picture Library

The one hopeful aspect of our own developing catastrophe is that humans are the driving cause this time, unlike in previous extinction events. That means humans could still develop a remedy. Mr. Brannen points out that we have successfully acted in the past to address human threats to the planet’s atmosphere. In the 1980s, for instance, NASA simulations of continued use of chlorofluorocarbons showed the ozone layer almost completely disappearing by 2060 and spawning what he calls “a global wave of lethal mutations and cancers.” Instead, 197 nations came together to ratify the 1989 Montreal Protocol, which set the ozone layer on a course to recovery by the middle of this century. In the U.S., the 1989 amendments to the Clean Air Act likewise quickly reduced the threat of acid rain and led to dramatic improvements in the quality of the air we breathe. Both of those initiatives began under Republican administrations, and the current administration could still take that kind of bold, forward-looking action on climate change. The lesson from the unimaginable devastation of past extinction events is that we have everything to lose by continued delay.

 

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