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When Life Nearly Died: The Greatest Mass Extinction of All Time

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Michael J. Benton's text, When Life Nearly Died, is superb. The topic of the book is the end-Permian extinction, an event less known to the average reader but of far greater impact than that of the KT boundary extinction of the dinosaurs. Although not necessarily as emotively compelling or as dramatic as the latter, the Permian devastation left the planet with only 4-10% of its previous species. It was a bottleneck of major consequence for subsequent biodiversity.

I would recommend this volume to any general reader with an interest in paleontology and earth history. The book covers the early history of geology and especially the biographies and activities of those researchers who helped define the rock sequences which every student memorizes: Precambrian, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous, and Tertiary. He focuses particularly on those who clarified the facies of the Permian and Triassic and brought to light the fact that "something funny" was going on then.

Although no real background in geology is needed to comprehend the narrative, I suspect that most will find the first chapters more interesting than later ones. The author touches upon subjects like uniformitarianism and catastrophism and the disagreement between them and upon the scientific free-for-all that arises over new theories like the impact demise of the dinosaurs, making them quite clear for the average reader. He subsequently builds upon the basics he has provided to carry one through his thesis. Once he gets into the actual discussion about the causes of the Permian event, however, the discussion settles down to chemistry, especially atmospheric and oceanic chemistry: how they work, how they interact, and how they can go horribly wrong. This may be a little tougher going for some readers. For those expecting a definitive answer to what caused the extinction, they will be disappointed. While there are contenders aplenty, the author honestly admits that there is not yet a clear winner and the ultimate cause may be multifacited.

I was especially impressed by the author's ability to stay on track. He gave a good background discussion, added some information about his own contributions, discussed the theories currently entertained by the geological community and ended with a discussion about biodiversity and human impact on the environment. In short the book was about the Permian extinction with enough support material to help a non-professional reader understand it and was not a platform for an autobiographical ego trip. He also gave a very clear and unbiased account of other scientists' work and how their efforts fit into the whole picture. In short he gave credit where credit was due.

A superb overview of the Permian extinction

Distinguished vertebrate paleontologist Michael J. Benton's latest book, "When Life Nearly Died: The Greatest Mass Extinction Of All Time", is a long overdue popular account of the worst mass extinction in Earth's history, the end Permian extinction of approximately 251 million years ago. Other customers have complained that this book only devotes less than a quarter of its text to the Permian extinction. However, Benton does an elegant job describing the rise of a uniformitarian view of geology in the 19th Century (One major omission is not citing Scottish geologist James Hutton, who can be regarded correctly as Charles Lyell's intellectual precursor with respect to uniformitarianism.) which was eloquent expressed and defended by Charles Lyell in "Principles of Geology", his influential text on geology which helped shaped the careers of other distinguished scientists, most notably Charles Darwin. Next Benton gives a mesmerizing account of the career of Scottish geologist Roderick Murchison, who coined the name Permian for a suite of rocks found in the Ural Mountains of Russia. These lengthy digressions are important - and will become apparent to the astute reader - once Benton describes the Permian mass extinction.

The second third of the book discusses the nature of mass extinctions, describing why paleontologists were inclined originally to think of mass extinctions as the result of apparent bias in sampling of the fossil record, not as real events denoting substantial loss of the Earth's biodiversity. Benton devotes much space to discussing possible scenarios for the end Cretaceous mass extinction, noting that that the asteroid impact theory proposed by Luis Alvarez, his son Walter, and their colleagues at Berkeley is the one accepted now by scientists. And he notes how ecosystems recover following a mass extinction, noting some of the important work done by ecologists and paleontologists in their analyses of recent ecological data as well as the fossil record.

In the final chapters Benton describes what he thinks did happen at the end Permian mass extinction, offering a plausible scenario for this event (However, he dismisses a probable impact scenario which may be more likely in light of current understanding of planetary impacts, most notably the work done by the Alvarez team and others for the terminal Cretaceous impact.). And he gives a thorough overview of man's negative impact on current biodiversity, noting that this could be yet another important extinction in Earth's history. Students of paleontology, historians of science and the general public will find this fine book a splendid overview of mass extinctions, especially the Permian extinction. It is one of the best recent books on the history of geology and paleontology that I have come across lately.

This book's title implies that it is primarily about the end Permian extinction, the largest known to science. In fact, direct discussion of that event occupies less than twenty per cent of the text. Much of the rest is a history of scientific ideas about the history of life and the great extinctions, with considerable attention to the individuals who advocated them. While the book is written in a readable style, the reader may be frustrated by the author's cautiousness in drawing conclusions about the Big One. The book ends with a discussion of what Benton calls the Sixth Extinction, caused by human activity, implying that it is comparable to the one at the end of the Permian. While this has become fashionable in popularized books about science, we haven't come near the Permian extinction level - yet.

I enjoyed the history of geology and especially the
history of establishing the Permian age itself. I
liked the thorough discussion of the Russian sites,
but as a geoscience professional I am probably more
inclined to this than the average reader. There was
also a good discussion of the KT event (that wiped out
the dinosaurs) and several other extinction events.
My gripe is that when he finally got around to the PTr
(Permian - Triassic)event, he basically explained why
certain hypothoses were not good, but didn't really
give a strong hypothesis of his own. Maybe that is
because the evidence is not good enough to have a strong
hypothosis, but the title is misleading in that case.
Overall, I recommend the book as a history of geology
and the Permian specifically, but don't expect to come
away with a real answer.

The public is being subjected to a litany of accounts of how life can, and has been, eliminated en masse. After learning ice ages may have swept away numerous creatures, we discovered dinosaurs may have been wiped out by the Big Rock. While trying to comprehend the amount of life an asteroid can dispose of, Michael Benton demonstrates the numbers pale in comparison to what a Big Burp can achieve. Combining his own field work with the research from numerous others, Benton skilfully builds a scenario of real mass destruction. His fine prose style keeps this book a compelling read throughout.

Sharply criticising Darwin's contemporaries and successors for clinging too resolutely to the notion that Nature's forces merely creep along, Benton notes the persistence of one theme. The "uniformitarians", he says, blinded scholars to the evidence - evidence that suggested life could end suddenly. Charles Lyell, one of Charles Darwin's inspirations, argued that what is seen today typifies the entire, and lengthy, history of our world. Slow, gradual change on today's surface is but the most recent example of the panorama of millions of years. Sudden change, "catastrophism", promoted by Baron Cuvier in France, was false. In life, Darwin's evolution by natural selection reflected the gradualist theme.

Benton dismisses Lyell and his adherents as overcommitted to gradualism. He contends they shut their eyes to contrary evidence. He admits the data was less than readily apparent, but argues some questions should have been raised long before now. New research, sometimes in places already once observed, finally brought reassessment. The Ural Mountains in Russia offered the first clues. Roderick Murchison toured there in the 1840s, naming the "Permian System" of rocks. Wars and revolutions interrupted the surveys and geologists and paleontologists peered at new ground. The Great Karoo of South Africa, China and other sites provided new information. A gradually emerging picture revealed a massive die-off 251 million years ago. What had happened?

After a long introduction of chapters recounting the researchers and their findings around the planet, Benton dismisses the notion of a bolide impact. This idea, fostered by the discovery that the Dinosaur Era had likely been concluded by the impact of a 10 kilometre asteroid, wasn't matched by the evidence. While the Permian Extinction may have been accompanied by darkened skies and deluges of rain, the real killer was something else. The dinosaur extinction wasn't typified by massive intrusions of poisonous gases, but the Permian was another matter. Benton surmises that 251 million years ago a series of volcanic fissures spewed immense waves of lava over the land near the North Pole. This area, now known as Siberia, is still covered by the remnants of the outburst. With the lava came noxious gas, mostly carbon dioxide and sulfur dioxide. These "greenhouse" gases warmed the seas, releasing life-killing methane. The catastrophe may have killed off up to 96% of all living things.

This is not simply an arcane analysis of events in the ancient past. It's a book that should gain a wide readership, since the events of all those millions of years ago have implications for today. Benton notes the sediments at the bottom of our seas contain a build-up of methane equalling or exceeding that of the Permian. Today's human-spurred global warming may be leading to the same scenario. Extinction, Benton reminds us, isn't limited to dinosaurs or other ancient life. It is clear that we must learn how these mechanisms work to make rational decisions about our dealings with the biosphere. [stephen a. haines - Ottawa, Canada]

The earth has been visited by no less than five massive extinctions of life during its nearly one billion years of recorded life. In WHEN LIFE NEARLY DIED, Michael Benton describes in terms that an educated layman can grasp of the processes behind such a troublesome concept. Benton divides such extinctions into three types: minor, intermediate, and major. His book title implies that the thrust of his interest will be with one that was the largest, the one that closed out the Permian, nearly 250 million years ago. Yet, most of his focus is on an overview of the development of the controversy between catastrophism versus steady statism as to which one better clarifies the whys and hows of the growth and near death of life on this planet. Had Benton added an "s" after "extinction" to his subtitle: The Greatest Mass Extinction of All Time, then he would have placed his text on a firmer footing. But I quibble. What he has accomplished is a well-researched and eminently readable account of what mass extinction means, how it could have come about, and how our planet possessed the resiliency to repopulate itself, even after the colossal near extinction of life at the end of the Permian. The first ten chapters prepare the reader for the biggest, baddest ruination of life that ever struck Earth. Benton spends considerable time in assessing the damage of a one time event--like the asteroid that slammed into this planet and wiped out the dinosaurs 65 million years ago. He notes that as bad as that one was--and it was plenty bad--that life reinvented itself in an amazingly short period of time. But it was the one that occurred 250 million years ago that proved the most interesting and paradoxically the least known mass extinction. Benton had the great good fortune to possess the most recent geological evidence that pointed a firm finger of blame at the Siberian Traps. These Traps were massive volcanoes that began to erupt more or less simultaneously and continued to do so for approximately ten thousand years. As these Traps began to erupt, they emitted a witches' brew of obnoxious sulphur dioxide gas that settled slowly around the globe. The consequences of these eruptions were a combination of greenhouse gases and warming in some parts of the earth, global cooling in others, acid rain nearly everywhere, and most pernicious of all a life deadening increase of global anoxia, a loss of oxygen that wiped out nearly ninty percent of terrestrial and oceanic life. Benton personalizes this impossibly complex series of geological crises by zeroing in on how these crises affected a family of Diocynodons, a reptilian ancestor of the dinosaurs. The Diocynodons are hungry, which is no surprise since their food supply has steadily eroded since the Traps began to eradicate the world's food supply millenia ago. They are also finding it increasingly difficult to breathe, again no surprise since the amount of breathable oxygen has also plummeted. The rain that covers the blighted landscape is acidic. The food chain from the smallest plankton to the biggest predator has collapsed. Only the lucky few life forms that can withstand these pummeling blows survive. But the Diocynodons, like the vast majority of earth's creatures, cannot. They die, and life on earth needs more than one hundred million years to rediversify to include the later dinosaurs who will rule until they in turn are wiped out by an asteroid slamming into the Earth 65 million years ago. And so the process continues until today. Benton closes with a timely warning that we are very much like the proud, if unthinking dinosaurs who think that yesterday will be like today, and today like tomorrow. WHEN LIFE NEARLY DIED is a much needed wake up call to shake us out of that fatal complacency.

The apparent central purpose of this book was to explain what it submits as the greatest worldwide mass extinction ever, the "Permian-Triassic Event", 252 million years ago, more or less. Though it doesn't convincingly achieve that goal, it is nevertheless an awfully goof read. There isn't enough known about the core subject to fill a book this size. So for background, Benton gives an excellent history of Geology and Paleontology, over the past 3 centuries, more or less. To bring it all to life in human terms, this includes personal histories of those who have made the greatest contributions to we know what we presume to know of the distant past. It covers the often bitter ideological split between "uniformitarianism," which holds that all natural history is the result of knowable, on-going natural processes, and "catastrophism," which claims that only major, unpredictable catastrophic events cause periods of accelerated change in the patterns of life on Earth.
Working up to the present, the story finally includes the travels and adventures of recent field researchers, Benton himself included, mainly in southern Africa and Russia, where most of the evidence of this "cold case" can be found, The book explains an impressive array of hypothetical events that might have caused mass extinctions, in enough detail so that the reader can judge their credibility. Everything is explained in appealing, down-to-earth terms - even possible personal experiences of some of the long dead victims
Comparing the development of this case to a trial, it puts forensic experts on the stand from a wide range of geological specialties, presenting specific - and often contradictory evidence - for different hypothetical causes of death. The span of estimates of the time of death range from within a year to possibly 10,000,000 years, more or less. From a juror's point of view, Benton does not prove his case "beyond reasonable doubt," nor even "within a preponderance of evidence." So the result must be a "hung jury," but its members are left with a knowledge of all the factors in the case that they might never have acquired, except perhaps by sitting thru a few paleontology courses, for future enjoyment of the subject.
Consistent with its structure as a good mystery, Benton's presentation of the complex but possible mechanism of the Permian-Triassic extinction is deferred until the final chapter. So I will not ruin the suspense and reveal it here, except to say that he, refreshingly, does not pontificate that a massive meteor impact was required to explain it. All in all, for anyone with an interest in anything that lived before there were dinosaurs, this book is a good read. I recommend it.

The best book yet written on the Permian extinction, "When Life Nearly Died" explores all of the possible mechanisms, and then provides the only quantifiable theory ever put forward. Benton's description and data on a rapid global warming followed by an enormous polar methane release of multi-billion tonnage is actually supported by some math that looks sound.

The meteor theory of the Permian extinction is unequivocally dismantled and others like continental drift are given deft handling. The relevance of the Permian extinction is startling to us now. If we warm the planet too much more, a huge gaseous release could erupt from beneath the oceans and wipe out 90% of all life.

There's nothing I can really say about this book which hasn't been more elequently stated elsewhere. Suffice it to say that the reader will become familiar with many of the early scientists which formulated current theory and recent advances in theories once thought absurd but are now considered pro forma, such as plate tectonics and catastrophism. While the title does imply unique focus on the Permian extinction (still its primary focus), it actually deals with the 5 largest extinction events. The book is not technical in nature at all, and should appeal to anyone who has a lay interest in the Permian period and similar epochs.

This is a masterfully written book on a little-known topic, the Permian "event" that caused the extinction of perhaps 90% of terrestrial and marine metazoa 251 million years ago. And what was that "event"? The author, Michael J. Benton, comes down on the side of the "Siberian Traps" a long episode of volcanism in what is now Siberia. I was sort of cheering for the asteroid, but we must go where the evidence leads, and it leads toward the traps. This is the best and most comprehensive book I have encountered on the subject of the Permian extinction. Much of the research the author cites is very recent and the work is still being conducted. Stay tuned.