Set in the Paleocene period when dinosaurs were dying out, Oppel chroni cles the early life of Dusk, a chiropter who, unlike the others in his colony, is missing a digit and fur on his sails. Over time, Dusk realizes how different he is as he tries to fit in with his gliding relatives, suppressing his strong impulse to fly like birds. When the colony is threatened by carnivores, Dusk’s ability to echolocate and fly becomes important as the chiropters evade predators on their migration to a new and safer home. Oppel ably drops the reader into the fascinating and evolving world as it could have been sixty-five million years ago. Prequel to Oppel’s bat trilogy Silverwing, Sunwing, and Firewing. 2008 Ruth and Sylvia Schwartz Children’s Book Award, 2008 CLA Book of the Year Award for Children (Shortlist). sc