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Chapter 14
Themes
Key
LitCharts assigns a color and icon to each theme in A Short History of Nearly Everything, which you can use to track the themes throughout the work.
Science, Discovery, and Mystery
Writing, Wonder, and Inspiration
Progress, Sexism, and Dogma
Existence, Awe, and Survival
Summary
Analysis
In the 1960s, a man named Bob Christiansen, who works for the United States Geological Survey, is confused to find no evidence of a volcano in Yellowstone National Park. This is odd because volcanic activity accounts for the park’s geysers and hot springs. When most people envision a volcano, they think of cone-shaped volcanoes like Japan’s Mount Fuji—but there’s another, more explosive type called a “caldera” which burst so quickly that they just leave a subsided pit behind. This kind of volcano is what Christiansen is looking for. By chance, NASA had recently sent some high-altitude pictures of Yellowstone to the park officials, and Caldera is shocked when he sees them—he realizes that the entire park is a caldera that’s 40 miles wide, making Yellowstone a supervolcano.
To emphasize how perilous life on Earth is, Bryson discusses calderas, or supervolcanoes, like Yellowstone, which are so massive that they can only be seen from space. Even if we think we’ve identified the dangerous spots on Earth—like active volcanoes and fault lines between tectonic plates—there are still many others that may not be visible to us. A eruption from a caldera the size of Yellowstone would likely have devastating impacts on Earth’s life forms, yet this volcano was only discovered in the 1960s. The fact that this discovery was so recent reinforces the idea that human knowledge about Earth is highly limited.
Themes
Bryson says that essentially, Yellowstone’s visitors are walking on something with the explosive power of an eight-mile-high pile of TNT the size of Rhode Island. Yellowstone sits on a “superplume”—a vast bowl of unstable magma that can burst explosively or pour out a fast-flowing “flood” of molten rock. There are about 30 active plumes on Earth, but the others are all in the ocean. They’re responsible for creating most of the world’s island chains, including Hawaii, the Galapagos, and the Canaries. Nobody knows why Yellowstone’s superplume is on land. It means that Earth’s crust is very thin there and that it will likely burst explosively rather than bubbling out slowly.
Bryson stresses the dangers of sites like Yellowstone by comparing them to massive bombs waiting to go off. He describes unstable magma and explosive molten rock floods to help the reader visualize that when Yellowstone next explodes, life around it will be completely defenseless. Furthermore, the fact that Yellowstone is on land instead of under the sea remains a mystery, showing how little scientists know about this phenomenon and the threat to life that it bears.
Themes
Scientists know that the Yellowstone supervolcano erupted 16.5 million years ago, and it’s blown up about 100 times altogether. There’s nothing comparable to this in human experience. The closest comparison to be made is with Krakatau in Indonesia, which erupts in 1883 with a bang that “reverberate[s] around the world for nine days” and ejects golf-ball sized lumps of molten rock. Yellowstone, however, would eject something more like car-sized molten rock chunks. 2 million years ago, a Yellowstone eruption expelled enough debris to bury New York State 67 feet deep in ash. The eruption covered nearly the entire United States, likely destroying the soil for years to come.
Bryson emphasizes that the scale of a supervolcano eruption far exceeds anything humans have experienced. He wants to show that even the worst catastrophes in human history so far come nowhere near to capturing the threats we face from volcanic activity at every passing moment of the day. Even if a person isn’t near the eruption site, the effects on soil and the atmosphere would make life even less sustainable than it already is. It really is a matter of luck that none of this has happened to us so far.
Themes
Another supervolcano eruption in Sumatra 4,000 years earlier triggered at least six years of “volcanic winter.” Scientists think that the altered climate probably all-but-destroyed humans then, probably reducing the global population to a few thousand. Some evidence suggests that it takes 20,000 years for the human population to grow larger again. In 1973, the park develops an “ominous bulge” before swelling and subsiding again over the next 20 years—and geologists realize that Yellowstone isn’t dormant but active. They estimate an eruption happens every 600,000 years. The last one was just over 600,000 years ago. “Yellowstone, it appears, is due,” Bryson warns.
Bryson emphasizes that although human life hasn’t witnessed a Yellowstone eruption, the threat is imminent because Yellowstone is active. Once again, it’s not a matter of chance (like an asteroid impact). Rather, it’s inevitable that Yellowstone will erupt (probably soon)—meaning that human life faces a very real, imminent threat. Bryson thus reinforces the idea that humans should be in awe of the planet’s power.
Themes
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Bryson asks Paul Doss, Yellowstone National Park’s geologist, when he thinks Yellowstone might erupt, but Paul Doss says it’s hard to know. Italy’s Mount Vesuvius was active for 300 years but stopped in 1944, and nobody knows why. There might be seismic shocks beforehand, but Yellowstone already gets about 1,200 of those a year. In 2000, an organization called “YVO” is created to study Yellowstone’s activity and draw up a “hazard plan” in case it blows. Doss hopes that they’ll come up with one soon. Of course, it might take another 10,000 years for Yellowstone to erupt, or it might not erupt at all.
Doss’s discussion with Bryson shows how unprepared humans are for such a catastrophe, meaning—as with potential asteroid impact—when the next one happens, we’ll have no defenses. Even when humans know a catastrophe is imminent, we are still highly vulnerable due to the insurmountable scale of the disaster. Bryson emphasizes that our knowledge is limited to knowing that Yellowstone is due to erupt, but on the geological scale this could mean tomorrow or in thousands of years. Thus, our knowledge in anticipating this event more specifically is also limited.
Themes
Bryson points out that there are also other dangers in Yellowstone: in 1959, for instance, a 7.5 magnitude earthquake collapses an entire mountainside, creating a massive landslide that kills 28 campers. Yellowstone, it turns out, it also an earthquake fault zone. To Bryson, the “grandeur and inexorable nature of geological process” is evident in the Teton mountains, just south of Yellowstone. They’ve been growing six feet per year from tectonic plate activity every 900 years. The last time that happened was 6,000 years ago, so they’re “overdue” as well. Hydrothermal explosions are also a concern: Yellowstone has 10,000 geysers, which is more than the rest of the world combined, and they explode without warning.
To reinforce the idea that humans face perpetual threats to our existence, Bryson lists other dangers—beyond a caldera explosion—that are evident in Yellowstone, citing seismic activity and hydrothermal explosions, both of which humans are highly vulnerable to. Worse still, scientists have little to no grasp on predicting when such events will happen, meaning that scientific knowledge about Earth’s interior is not just limited—it barely exists.
Themes
In 1965, husband-and-wife biologists Thomas and Louise Brock discover—to their surprise—living microbes in some of the scum around Emerald Pool, one of Yellowstone’s pools of boiling water. Before their discovery, scientists believed that no life could live in sumptuous, acidic environments at that temperature. Meanwhile, scientists begin finding even tougher microbes that need to live in very hot environments. Now, scientists are no longer sure what the upper limit to sustain life is. Life, it seems, is more “clever and adaptable than anyone had ever supposed.”
The Brocks’ discovery of microbes that can survive in conditions previously thought to be inhospitable to life shows that scientific knowledge in biology—as in physics and chemistry—is limited. The more creatures that scientists discover, the more they learn that their prior assumptions are false. The fact that microbes can exist in such conditions at all also shows that life’s ability to thrive is astounding: it continues to crop up in the most unlikely places.
Themes
