In this young readers edition of the New York Times bestselling, Pulitzer Prize-winning The Sixth Extinction, Elizabeth Kolbert tells us why and how human beings have altered life on the planet in a way no species has before.Over the last half a billion years, there have been five mass extinctions, when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs. Adapting from her New York Times bestselling, Pulitzer Prize-winning adult nonfiction, Elizabeth Kolbert explores how humans are altering life on Earth