The paleontologist Michael Benton describes a mass extinction event as a time when “vast swaths of the tree of life are cut short, as if by crazed, axe wielding madmen.” Elizabeth Kolbert‘s new book, The Sixth Extinction: An Unnatural History (Henry Holt, 2014), explores the five major mass extinction events that have occurred on the Earth over the last half billion years. Kolbert contrasts these Big Five, as they are known, to the sixth mass extinction event, which we are in the midst of today. This time, instead of a massive asteroid or a sudden glaciation event, humans are the culprit. Travelling with different scientists to remote ecosystems around the world, Kolbert sees evidence of the many ways humans are altering the planet – through climate change, ocean acidification, and the spread of invasive species. By the end of the century, scientists predict we will lose 20 to 50% of all living species. Kolbert also places this current extinction event in the context of human history: although the rate at which we are driving species extinct has reached an unprecedented pace, humans have been responsible for causing species loss for tens of thousands of years. As Kolbert comments, “We’ve been at this project for a very long time.” Her book also addresses the paradoxical relationship that humans have with the species we share the planet with, especially the large and charismatic megafauna. Kolbert contrasts our remarkable proclivity to kill off species with some touching examples of the inexplicable lengths we will go to save a species from extinction. Elizabeth Kolbert has been a staff writer with The New Yorker since 1999. She is also the author of Field Notes from a Catastrophe: Man, Nature, and Climate Change. Learn more about your ad choices. Visit megaphone.fm/adchoicesSupport our show by becoming a premium member! https://newbooksnetwork.supportingcast.fm/environmental-studies