See what a vampire bat has in common with a sperm whale. Find out what sets a vampire bat apart from a walrus or a groundhog. Readers will compare and contrast key traits of vampire bats--their appearance, behavior, habitat, and life cycle--to traits of other mammals. Charts and sidebars support key ideas and provide details. Through gathering information about similarities and differences, readers will make connections and draw conclusions about what makes this animal a mammal and how mammals are alike and different from each other.