The Sixth Extinction Summary and Analysis

Prologue and Chapter 1 Summary

A new species emerges, adapting, innovating and traveling. It overcomes bigger animals and learns to travel across water. This “young species” encounters a similar older species to interbreed with and then, “by one means or another, kill[s] them off.” Homo sapiens begins to change Earth’s atmosphere, climate and oceans. The impact of humans on Earth closely mirrors events that led to the other “Big Five“ extinctions, ushering in a sixth.

Amphibians have existed since before the dinosaurs but now are nearing extinction. In the past 30 years, the endangerment of frogs has increased, which is particularly evident through the near elimination of Panama’s golden frogs. This situation leads some researchers to state that the “Sixth Extinction” is underway. A die-out of blue poison-dart frogs has been caused by the fungus Batrachochytrium dendrobatidis (Bd), which limits amphibians’ ability to absorb electrolytes. Bd has spread throughout the world and can live in areas even where no more amphibians survive, which paints a bleak picture for their future.

There are two types of extinction. “Background extinction” occurs constantly. Scientists measure it using fossils and believe it has a rate of one species every 700 years. “Mass extinction” occurs when a species disappears in a geologically short period of time. If a mass extinction is underway, amphibians aren’t the only species at risk.

Prologue and Chapter 1 Analysis

From a narrative perspective, Kolbert separates herself from her own species to describe the emergence of humans on Earth as they survived poor odds. She portrays them as both savage and industrious. Kolbert’s vivid description of how homo sapiens interbreed with similar species, then “by one means or another, kill them off,” paints them as brutal. She shows how humans inherently alter Earth’s systems, setting up humans as the antagonist in her story. It should come as no surprise, then, that in Chapter 1, humans are identified as the cause of the Sixth Extinction.

Kolbert’s discussion of the dangers facing the Panama golden frog and the blue poison-dart frog reveals that the world is on the brink of disaster—an idea she’ll continue to explore throughout the text. She begins to understand that the amphibian crisis isn’t isolated but that the scope of the issue is massive. Amphibians have historically been able to survive in difficult habitats. The reader can infer: if amphibians can’t survive, what else might be in danger?

Each chapter in The Sixth Extinction follows a pattern in which Kolbert interviews experts, travels the globe to witness and report on scientific events, and claims that humans are causing irreversible damage to the planet.