Summary

In "The Sixth Extinction: An Unnatural History," Elizabeth Kolbert explores the ongoing sixth mass extinction event, driven by human activity. The book weaves together personal anecdotes from Kolbert's travels to research sites around the globe, scientific discussions with leading experts, and profiles of specific species that have either disappeared or are teetering on the brink.

Kolbert begins by explaining the concept of mass extinction, emphasizing its rarity and catastrophic impact on the planet's biodiversity. She then dives into the past, examining the "Big Five" mass extinctions that have previously reshaped life on Earth, highlighting the theories behind these events, like the asteroid impact that wiped out the dinosaurs. These historical accounts serve as a backdrop for understanding the devastating consequences of rapid environmental change.

The book then shifts its focus to the present, documenting the various ways human actions are pushing species toward oblivion. Kolbert investigates habitat destruction, climate change, ocean acidification, invasive species, and the ripple effects of these forces on delicate ecosystems. Through her travels, she encounters dying frogs in Panama, disappearing bats in the northeastern United States, struggling corals on the Great Barrier Reef, and dwindling rhino populations, illustrating the global scale of the crisis.

Kolbert also explores the ways humans have fundamentally altered the natural order, rearranging the biota of the planet and creating a "New Pangaea" through global trade and travel. She discusses the challenges and ethical dilemmas of captive breeding programs and the increasing reliance on technological interventions, like the Frozen Zoo, to preserve genetic material in the face of extinction.

Finally, Kolbert reflects on the implications of the Sixth Extinction for humanity itself. She argues that by disrupting Earth's systems, we are jeopardizing our own future. The book concludes with a haunting image of the Hall of Biodiversity at the American Museum of Natural History, where visitors unknowingly walk over the remains of past extinction victims, standing on the very spot where the casualties of the sixth extinction will soon be placed. Kolbert leaves the reader with the stark realization that human actions are not only driving other species to extinction but are also busy sawing off the limb on which we perch.