Gr 4-6 This intriguing book explores both the history of extinction-dating back to the mass extinction of the Ordovician period 450 million years ago and the extinction of the dinosaurs 65 million years ago-as well as the possibility of the extinction of species in existence today. It is reminiscent of Don Lessem's Dinosaurs to Dodos (Scholastic, 1999), although Extinction! is less a gallery of extinct animals and more a fascinating exposition of what the majority of scientists think our planet's future holds. In addition to describing the history of mass extinctions on Earth and smaller-scale extinctions of individual species, whether brought about by human action or not, Newland considers possible scenarios that might end life on Earth: an asteroid colliding with our planet, a supervolcano, a deadly virus, or an exploding nuclear bomb that blocks out the sun. Children will find the chapters on the extinction of species of the past fascinating on their own. However, the most thought-provoking aspect of this book that makes it stand out from others on the same topic is the attention given to the interconnectedness that the extinction of one species from one ecosystem has with another ecosystem, and how this, if continued, might contribute to the eventual extinction of human life on Earth. This title is a solid contribution to any collection on paleontology and life sciences. Anne Barreca, New York Public Library