“The Sixth Extinction: An Unnatural History” is a book about extinction and the impact of humanity on a living planet. This article is a part of this month’s mini-theme, Extinction. For more articles in this theme, click here.

Over the past 500 million years, dramatic and catastrophic worldwide changes have completely reshaped the order of life.
Five major episodes of mass extinction are known to have taken place. The most recent and most familiar of these events occurred 66 million years ago, spelling the demise of the dinosaurs, among others.
Scientists today conclude that we have entered a sixth mass extinction period, with humans as the driving factor. Elizabeth Kolbert places this sixth extinction in the context of life’s history, as we know it, which demonstrates the fact that “life is extremely resilient but not infinitely so.”
Kolbert’s book, “The Sixth Extinction: An Unnatural History,” is a bridging of the past and present, of scientific history and current research that sheds light on the devastating effects of human activity and the impacts of climate change on global biodiversity, which a number of recent studies have shown.
Central to the book is the notion that industrialization and globalization have ushered in a new epoch, referred to by many as the Anthropocene. This term was popularized in 2000 by Paul Crutzen, a Dutch chemist who shared the Nobel Prize for his discovery of the depleting effects of certain compounds on atmospheric ozone. In short, now is a time when humans have become a major geological force, one “which has no analog in earth’s history,” Kolbert writes. We are significantly altering the Earth’s land, ocean, atmosphere, and life in a way that “no other creature has ever managed.” By doing so, we also are putting ourselves at risk.
In each chapter, Kolbert supplies vividly rendered firsthand experiences blended artfully with stories of the scientific past and accurate scientific information. She chronicles her travels to unique locations around the world: from the jungles of Panama to the Andes mountains, from a dirty creek in New Jersey to a remote isle off the coast of Iceland. She joins researchers of various disciplines, each providing important perspectives, insights, and evidence supporting the argument that a mass-extinction is taking place right before our eyes, even in our “own backyards.”
The book delivers intimate and tragic case studies of many individual species, some now gone, some facing a similar fate. The great auk, a bird known as the “original penguin,” falls victim to brutal exploitation by European settlers. A warming and acidifying ocean threatens coral reefs, making them likely “the first major ecosystem in the modern era to become ecologically extinct,” according to scientists. Hundreds of types of native Hawaiian snails are erased due to human introduced invasive species. The Sumatran rhino, once common in Asia, is reduced almost entirely as a result of habitat degradation and fragmentation.
The rise of extinction, and subsequently mass extinction, as accepted scientific ideas is another theme that persists throughout the work. This starts in the 17th century with Georges Cuvier, the French zoologist and paleontologist who irrefutably established the extinction of past life forms after examining fossil remains of large bygone mammals like the American mastodon and wooly mammoth. The “series of paradigm shifts” in the development of these ideas is a compelling story that enriches the narrative and provides valuable background to our understanding of extinction today.
As dire as the premise of the book is, Kolbert presents it in a way that is engaging and honest. She can be brazen and genuinely funny in the same passage. Her message is also not entirely devoid of hope. Even though “humans can be destructive and shortsighted” she writes, “they can also be forward-thinking and altruistic.”
She argues that time and again, people have demonstrated that they care and are willing to make sacrifices for other creatures. But the real point, she says, is “it doesn’t much matter whether people care or don’t care. What matters is that people change the world.”
“The Sixth Extinction: An Unnatural History” is an excellent exposition that forces the reader to think deeply about humanity, the value of life, and the “the problem of sharing our earth with other creatures.”
“Right now,” Kolbert declares, “we are deciding, without quite meaning to, which evolutionary pathways will remain open and which will forever be closed.” This may, she adds, “unfortunately, be our most enduring legacy.”