The Panamanian town of El Valle de Antón, is located within a massive volcanic crater. Until very recently, golden frogs were an extremely common sight in El Valle. This species was known to be extremely toxic. Thus, when the golden frogs of El Valle began to disappear, few people saw it as a crisis.
Like the Prologue, Chapter One begins on a slightly mysterious note: what happened to the golden frogs of El Valle de Antón, a species that used to be ubiquitous in the community?
Kolbert herself found out about the golden frogs of El Valle in a children’s nature magazine. The magazine said that biologists in the town were trying to build a special facility to save the golden frogs; in the meantime, they captured a few dozen frogs and kept them in a “frog hotel,” where they pampered the frogs and fed them well. Around the same time, Kolbert came upon a scientific article arguing that the world was in the midst of a sixth mass extinction, which would be devastating for amphibians and many other life forms. According to the article, there had been five previous mass extinctions, the most recent of which took place during the Cretaceous period, when, famously, the dinosaurs died out. Kolbert was so struck by the article on mass extinction that she bought a ticket to Panama to learn more—surely a mass extinction, one of the rarest events in the history of life on Earth, was worth researching.
In this passage, Kolbert establishes herself as a kind of “character” in her own book. In addition to being a history of the science of extinction, The Sixth Extinction describes some of Kolbert’s travels around the world to learn about wildlife preservation and the vanishing natural world. The passage is also important because it emphasizes Kolbert’s role as an “interpreter” between the scientific community and the general public. Kolbert isn’t a researcher or an environmental specialist; however, she plays a crucial role—she interviews scientists and presents their ideas in a clear, understandable manner.
In El Valle, Kolbert visits the El Valle Amphibian Conservation Center, or EVACC, which is largely devoted to saving the golden frog, or Atelopus zeteki, from going extinct. Edgardo Griffith, the director of the EVACC, is a young man who has spent most of his adult life studying different amphibians. Griffith claims that the world is losing frog species before people even know they exist. Though this is a tricky claim to prove, the fringe-limbed tree frog (which was discovered in 2005 and went extinct in the wild a few years later) suggests that it’s possible, if not likely.
As Kolbert researches the disappearance of the golden frog, she begins to learn about the scope of the problem facing the world’s frog population: many different species (not just the golden frog) are dying out, for reasons that Kolbert doesn’t know yet.
The extinction of frog species is particularly noteworthy because, historically, frogs are some of nature’s most resilient animals, capable of surviving in many different environments. The earliest amphibians appeared millennia ago, when the Earth’s land was part of one landmass, now known as Pangaea. Today, there are at least 7,000 different frog species, which inhabit environments as different as the Arctic Circle and the Mojave Desert.
Different classes of animal go extinct at different rates, and, traditionally, frogs are an unusually resilient class of animal. Therefore, the fact that even frogs are going extinct doesn’t bode well for the other plants and animals of the Earth. What, the passage implicitly asks, could be killing frogs, given that they can survive in the Arctic and the Mojave?
Why are frogs going extinct in the 21st century? One might think that frogs are disappearing in areas where many human beings live; however, frogs that live in pristine areas, where no humans live, are also going extinct. One of the first clues about what was killing frogs came from the National Zoo of Washington, D.C. A few years ago, the zookeepers discovered that their population of blue poison-dart frogs was dying off, thanks to an unidentified fungus called Bactrachochytrium dendrobatidis, or Bd, for short. Kolbert learned that the same mysterious fungus, Bd, had killed off most of the golden frogs in El Valle. Bd has also spread to Colombia, Australia, and New Zealand, decimating the frog populations.
The literal cause of the golden frogs’ extinction is the arrival of Bd in El Valle. But, of course, in light of Kolbert’s central concern with the impact of human activity and the ominous notion that frogs are dying where there are no humans, this passage raises the stakes beyond Bd in El Valle. It suggests that El Valle is symptomatic of a larger pattern of extinctions that is a ripple effect from human activity.
The distinction between “mass extinction” and “background extinction” is crucial to understanding the significance of mass extinction. Over millennia, scientists can expect a few species to go extinct—this is “background extinction.” During a mass extinction, however, a huge number of species go extinct in a far shorter time period. One could say that the history of life on Earth consists of “long periods of boredom” (background extinction), punctuated by “panic” (mass extinction).
Here, Kolbert introduces the idea that, at different points in planetary history, the Earth’s life forms have faced the threat of mass-extinction caused by changing environmental factors. Also notice the way that Kolbert alternates between passages on specific species and places (like the golden frogs in El Valle) and a more general analysis of extinction theory. Kolbert will use a similar technique throughout the book, using her investigations into specific species to illuminate her general analysis, and vice versa.
In the modern era, amphibians are the world’s most endangered class of animal—they seem to be going extinct at a rate 45,000 times higher than the background rate. However, there are many other classes of life, including corals, mollusks, sharks, rays, birds, and mammals, that are going extinct at a roughly comparable speed.
Traditionally, amphibians are one of the most resilient (and, in a sense, “extinction-proof”) kinds of animals. But now, it would seem, amphibians are more endangered than any other kind of animal—demonstrating that useful evolutionary traits don’t always remain useful over time (a point that Kolbert will make again in later chapters).
Returning to Bd, Kolbert explores the mystery of why the fungus has spread around the world so quickly. Some argue that humans unintentionally spread Bd around the world in the 1960s, since it was an ingredient in a popular pregnancy test. Others speculate that North American bullfrogs spread Bd to other continents after human beings spread bullfrogs to Asia, Africa, and South America. In either case, the reason for the spread of Bd is the same: human travel, which has produced an “intercontinental reshuffling” that is “unprecedented in the … history of life.”
Having identified Bd as the cause of frog extinction, Kolbert explores a deeper cause of this problem: humans altering their environments. Humans travel around the world, taking new microbes, fungi, and animals with them wherever they go. As Kolbert will show, humans are interfering with the natural “equilibrium” of the Earth, accelerating the process of mass-extinction.
One day, Kolbert goes with Griffith to explore the El Valle area for frogs. They drive through the rainforest and wait for night to fall (most amphibians are nocturnal). After a while, Griffith spots a San Jose Cochran frog, which he scoops up with gloves, and swabs to test for Bd. Griffith continues, swabbing many different species of frog. He brings two species back to EVACC: a blue-bellied poison frog, and a pale salamander, whose species he was unable to identify. Kolbert realizes that the two creatures Griffith took back to EVACC would never live in the rainforest again—they’d probably die in glass tanks.
Although the human race as a whole seems to be driving golden frogs (and other creatures) into extinction, there are individual human beings, like Griffith, who are trying to save species from extinction. Even so, Kolbert notes the small scale of the gesture—even if Griffith can save individual frogs from extinction, he can’t preserve their natural rainforest habitat.