Rating: 
Summary: A good read
Review: Clever writing, fascinating scientific controversy. I loved it.
Rating:
Summary: Splendid Look At A New Controversial Theory of Geology
Review: Gabrielle Walker's "Snowball Earth" reads like a gripping detective tale and spellbinding memoir. Her relatively terse epic primarily tells the tale of arrogant, maverick Canadian geologist Paul Hoffman, and how his study of Precambrian geological formations in Namibia, Africa lead inexorably to a new, controversial theory in the geological sciences; "Snowball Earth". Possessed by a zeal equalled only by a religious fanatic, Hoffman, a professor of geology at Harvard University, gradually builds up an impressive theory explaining how the Earth was encased in ice, not once, but probably at least four times, over the course of two hundred million years (He believes it began around eight hundred million years ago.). Furthermore Hoffman has suggested that this was the event which triggered the evolution of metazoan life and the subsequent Cambrian explosion of metazoan phyla. Walker also introduces us to Caltech geologist Joe Kirschvink whose work in magnetostratigraphy supplied important clues that aided Hoffman in shaping his theory. But to her credit, she also spends considerable time discussing important critics such as Columbia University's Nicholas Christie-Blick and University of California, Riverside's Martin Kennedy and noting their substantial objections without sounding dismissive. Told in engaging lyrical prose, Walker's book will interest anyone fascinated with research done by field as well as laboratory geologists. Her book is a splendid little ode to exciting state-of-the-art geology and some of its most fascinating scholars, most notably Hoffman, himself. Without question, this is among the finest popular books on geology that I've come across.
Rating:
Summary: Splendid Look At A New Controversial Theory of Geology
Review: Gabrielle Walker's "Snowball Earth" reads like a gripping detective tale and spellbinding memoir. Her relatively terse epic primarily tells the tale of arrogant, maverick Canadian geologist Paul Hoffman, and how his study of Precambrian geological formations in Namibia, Africa lead inexorably to a new, controversial theory in the geological sciences; "Snowball Earth". Possessed by a zeal equalled only by a religious fanatic, Hoffman, a professor of geology at Harvard University, gradually builds up an impressive theory explaining how the Earth was encased in ice, not once, but probably at least four times, over the course of two hundred million years (He believes it began around eight hundred million years ago.). Furthermore Hoffman has suggested that this was the event which triggered the evolution of metazoan life and the subsequent Cambrian explosion of metazoan phyla. Walker also introduces us to Caltech geologist Joe Kirschvink whose work in magnetostratigraphy supplied important clues that aided Hoffman in shaping his theory. But to her credit, she also spends considerable time discussing important critics such as Columbia University's Nicholas Christie-Blick and University of California, Riverside's Martin Kennedy and noting their substantial objections without sounding dismissive. Told in engaging lyrical prose, Walker's book will interest anyone fascinated with research done by field as well as laboratory geologists. Her book is a splendid little ode to exciting state-of-the-art geology and some of its most fascinating scholars, most notably Hoffman, himself. Without question, this is among the finest popular books on geology that I've come across.
Rating: 
Summary: Ediacarans on Ice
Review: Gabrielle Walker's book, and her companion article in *New Scientist* (Ice Magic, 12 April 2003, p. 30) chronicle the debate surrounding Snowball Earth theory. Unfortunately, the writing in both suffers from flawed interpretations and credulousness on Walker's part. For example, Walker reports "bellyflop" structures associated with Ediacarans as evidence that the creatures were swimming animals. The putative evidence suggesting that Ediacarans were swimmers is extremely weak; a more reasonable interepretation is that the "bellyflop" structures are simply impressions made by otherwise motionless Ediacarans as part of their cohort was stripped off the sea floor by ocean currents.Walker's book would have benefitted from a more lucid rendering of the scientific uncertainties involved. Did the earth's surface really freeze solid? Were the Ediacarans animals or something else? The jury is not in on these questions and in her race to tell the story Walker has perpetuated fallacies that obscure what *really* happened. The book also suffers from a lack of illustrations. Geology is truly a visual science, and preparation of at least a few illustrations might have helped avoid some of the problems noted above.
Rating: 
Summary: A Snow job or a revelation?
Review: Gabrielle Walker's first book portrays the struggle of a renegade scientist to establish a theory of evolution's progress. Charles Lyell's established "uniformitarianism" in geology, followed by Charles Darwin's application of it in his theory of evolution by natural selection. The concept of gradual change in life as reflected in the fossil evidence is being challenged by some scientist. Paul Hoffman's research in Namibia indicated that Earth was subjected to an intense Ice Age prior to the Cambrian, severely interrupting life's progress. Walker introduces us to Hoffman and other major contestants in this game of reading the rocks. She presents him and the arguments with dynamic style, giving the book a certain panache. Even under Walker's admiring scrutiny, Hoffman doesn't appear as an endearing figure. Yet, the very characteristics some find irritating are the same drives that kept the theory of Snowball Earth alive. Walker shows how combative science can be, with contenders sniping and quarreling like feuding families. They all have fossils, climate mechanisms and glacial processes on show. Walker attempts to give them all a hearing, but the opponents make but cameo appearances. She gathered her evidence by extensive journeys - her travel budget must have been prodigious. Walker reveals their peccadilloes and their strengths. When you are done, you feel a sense of identity, even intimacy with them. Whether you are convinced of the thesis remains problematic. Walker's own sketchy knowledge forces a pause, wondering about the validity of her presentation. Her admission of being a "Snowball Earth groupie" erodes credibility. She offers many assertions as givens, such as the asteroid dinosaur extinction thesis. Theory popularity is good journalism, but sketchy science. Her journalist role leads her to overuse of buzzwords - "Slimeworld", the habit of bacteria to form mats - achieves fatiguing redundancy. The predominant question, which Walker addresses only superficially, examines what process life underwent under these conditions. There was life before the Cambrian - clearly multi-cellular. How complex was it, and how resistant to the environmental crisis evoked by the Snowball Earth hypothesis? Ediacaran life was shallow sea bottom or surface dwelling. An ice blanket a kilometre or more thick would have been devastating to this population. Walker and her "group" are unable to form a coherent thesis of how life achieved complexity after the Snowball's meltdown, only that it must have happened - otherwise "we wouldn't be here". A valid statement, but one needing further support for how it might have occurred. Walker's personalised account makes engaging reading, presenting a new idea needing more attention. While various modifications of the Snowball Earth notion have been offered, final judgment remains deferred. This is a good, but limited, overview of the debate and the participants. At some point, someone qualified will enlighten us further. [stephen a. haines - Ottawa, Canada]
Rating:
Summary: A Snow job or a revelation?
Review: Gabrielle Walker's first book portrays the struggle of a renegade scientist to establish a theory of evolution's progress. Charles Lyell's established "uniformitarianism" in geology, followed by Charles Darwin's application of it in his theory of evolution by natural selection. The concept of gradual change in life as reflected in the fossil evidence is being challenged by some scientist. Paul Hoffman's research in Namibia indicated that Earth was subjected to an intense Ice Age prior to the Cambrian, severely interrupting life's progress. Walker introduces us to Hoffman and other major contestants in this game of reading the rocks. She presents him and the arguments with dynamic style, giving the book a certain panache. Even under Walker's admiring scrutiny, Hoffman doesn't appear as an endearing figure. Yet, the very characteristics some find irritating are the same drives that kept the theory of Snowball Earth alive. Walker shows how combative science can be, with contenders sniping and quarreling like feuding families. They all have fossils, climate mechanisms and glacial processes on show. Walker attempts to give them all a hearing, but the opponents make but cameo appearances. She gathered her evidence by extensive journeys - her travel budget must have been prodigious. Walker reveals their peccadilloes and their strengths. When you are done, you feel a sense of identity, even intimacy with them. Whether you are convinced of the thesis remains problematic. Walker's own sketchy knowledge forces a pause, wondering about the validity of her presentation. Her admission of being a "Snowball Earth groupie" erodes credibility. She offers many assertions as givens, such as the asteroid dinosaur extinction thesis. Theory popularity is good journalism, but sketchy science. Her journalist role leads her to overuse of buzzwords - "Slimeworld", the habit of bacteria to form mats - achieves fatiguing redundancy. The predominant question, which Walker addresses only superficially, examines what process life underwent under these conditions. There was life before the Cambrian - clearly multi-cellular. How complex was it, and how resistant to the environmental crisis evoked by the Snowball Earth hypothesis? Ediacaran life was shallow sea bottom or surface dwelling. An ice blanket a kilometre or more thick would have been devastating to this population. Walker and her "group" are unable to form a coherent thesis of how life achieved complexity after the Snowball's meltdown, only that it must have happened - otherwise "we wouldn't be here". A valid statement, but one needing further support for how it might have occurred. Walker's personalised account makes engaging reading, presenting a new idea needing more attention. While various modifications of the Snowball Earth notion have been offered, final judgment remains deferred. This is a good, but limited, overview of the debate and the participants. At some point, someone qualified will enlighten us further. [stephen a. haines - Ottawa, Canada]
Rating:
Summary: An Argumentative Champion for a Revolutionary Theory
Review: Geologists since the eighteenth century have advocated "uniformitarianism," the concept that what is going on to the Earth now is essentially the same as what has gone on before. It is a good rule of thumb, but like most rules of thumb, it requires intelligent neglect or violation, and working geologists do so to form an accurate picture of Earth history. There has sometimes been resistance to violation of the rule; the wipeout of the dinosaurs by an asteroid hit 65 million years ago is now generally accepted, but was not when it was proposed. But even without extraordinary outside forces, our globe used to be a very different place. Between 750 and 590 million years ago, there were sudden lurches in climate that froze even lands at the equator. Or so goes the Snowball Earth Theory. _Snowball Earth: The Story of the Great Global Catastrophe that Spawned Life as We Know It_ (Crown Publishers) by Gabrielle Walker describes the theory and its importance, but the current importance may not be merely its scientific significance. What makes the theory particularly interesting right now is that it is being championed by a colorful Harvard geologist who is attempting to make it accepted geological thought. Walker's surprisingly exciting book is thus not just a summary of ancient geology, but also an entertaining examination of personalities involved. The snowball Earth theory is not entirely new, but the book is largely the story of Paul Hoffman, a brilliant, driven geologist who was eager to make some sort of difference in his field. Argumentative, energetic, and brilliant, he has a strong reputation as a geologist and as a difficult character. Disputes by him are not objective quibbles published in obscure journals, but stand-up, screaming fights. Partially because Hoffman has taken up a sort of gladiatorial grandstanding for the theory (he has made his own contributions and confirmations), there are equally adamant anti-snowballers. The combative nature of science is on display here; Walker writes, "Science works at its best when somebody puts forward a theory and everyone else tries to pull it down." She is good at describing the pains of field work (something at which Hoffman is adept), but academic battles are the emphasis in her book. Of course Hoffman hopes his ideas share the same fate as those of Alfred Wegener, whose ideas about Plate Tectonics were originally ridiculed; so far, they have survived the challenges about which Walker reports. Particularly valuable in the theory is the light it might throw on the bloom of life into complex multicellular creatures. Of course a deep freeze would have been disastrous for all the simple slimes that were found all over the Earth when the freeze came. There might have escaped, however, pockets of cells that, according to the theory, were the precursors for the famous Cambrian explosion in the trilobite times. Perhaps the snowball produced the complexity, although this is far from clear. It is one of the many details that is going to have to be argued over. Walker winds up with a description of the Earth's future; if we are still around in a few hundred million years, we might well have to deal with a return of the snowball. It is too hard to think about time lengths of such spans, but geologists routinely do so, although the spans are back in the past. Walker's book is a good introduction to serious thought about such times, and to the very human way such science is done.
Rating: 
Summary: Snowballs and egos on the loose
Review: Great writing for the layperson interested in pre-quaternary climate change theory, but some of the geoscientists researching the 'snowball earth' appear to have personalities verging on the psychotic. Would make an excellent case study for psychiatrists studying the obsessions of the geoscientific research community. Some of these geologists should've had their egotistical butts coldly rocked when they were being raised. I feel sorry for their students.
Rating:
Summary: Great look at an exciting theory!
Review: I first heard about the Snowball Earth theory when I saw a documentary about it on the Discovery Channel. I'm usually more of an astronomy fan, but that documentary fascinated me. I picked up this book following that on a chance sighting, and it did NOT disappoint. The book covers the theory, in layman's terms, and the personalities behind the theory, both for and against. I think that the few poor reviews here are due to a misinterpretation of the book's purpose. Taken as a book meant to actually make a profit by interesting everyday readers, it was excellent. "Science snobs" who feel their points of view under-represented may take offense, but for the rest of us, thank you Miss Walker.
Rating:
Summary: One really has to work for the information
Review: I first heard about the theory of snowball earth in Ward and Brownlee's book Rare Earth and decided I wanted to read more about it, so when I ran across Walker's book Snowball Earth, I got it. The title and cover blurb suggested it was tailor made for me. Unfortunately I learned more about the egos of academe than I really wanted to know, and very little more about the geological theory than I had learned in Ward and Brownlee.
It's not that I don't have an interest in the personalities of men of science and history, nor do I expect them to be less "human" and more "above it all" than other people. Goodness knows Newton was a little crazy and more than a little petty, Di Vinci and Michelangelo were both difficult people, Pasteur was a patent scene stealer, and Tycho Brahe and Kepler both more than a little eccentric. It all makes interesting reading and reassures one that no matter how goofy one thinks oneself to be, there are others who are far worse and even more productive despite it all! Unfortunately Ms Walker's style is a bit "over the back fence" gossip. She seems to have an opinion about each of the characters about whom she writes and puts that opinion front and center. One comes away from the book wondering if the character of the players was more important to her than the subject of their discoveries and differences. As a result, one has to really work to get the information one bought the book for. Like Tolstoy, she exacts her price!
I'm not too sure to whom I'd recommend the book. I might suggest it for adolescents interested in the sciences and possibly in geology as a career, but I'm not too sure that the childish behavior of the scientists involved would be very encouraging to a young person. It would certainly be a reality orientation though: adults, even educated ones, can act immature; field geology and geologic theory are careers for the solitary and socially inept, so there's hope for the most introverted student; to achieve in academia, one must be as competitive as a barracuda, etc. On second thought, maybe the book isn't so good for kids.
As far as those interested in a topic that is fairly complex, the information about geology that the author interlaces into her text is quite accurate and comprehendible to even the most uninitiated on the subject, so the theory should make abundant sense. The book might even encourage such an individual to do a follow up on the field itself. Certainly there are a number of books on geology and earth history on offer on the Amazon.com web site.
For those with a background in geology and an interest in the topic of global glaciation, I think one would be better off with the journals: Science, Geology, Scientific American, and others. Most of these will be available in any university library, and some of them should be available in large urban libraries. Hitting a reference section should help one to find the relevant topic and reprints are often available.
|
