This engaging nonfiction picture book instructs young readers on the opposite of wintry hibernation: summery estivation, a more recently discovered seasonal sleep cycle engaged in by certain animal and insect species, including convergent ladybugs, the African lungfish, and the pixie frog. Stewart's prose balances a conversational tone with easily absorbed facts about estivating beings across several continents ("At the first hint of summer, a yellowbellied marmot heads underground for some serious shut-eye"), with some pages including additional information in a smaller font. Inset diagrams with species details plus near-photorealistic illustrations by Brannen make the subject matter more accessible for visual learners. Budding biologists will especially appreciate this intriguing primer on a lesser-known process. Back matter includes more about the animals depicted, suggested further reading, author's and illustrator's notes, and selected resources. Ages 6–9. (Apr.)

K-Gr 3—This picture book provides an appealing survey of a dozen animals that estivate. Brannen's simple, adept illustration on the cover introduces a pleasing pictorial scheme. The brief text highlights different places where animals sleep, including tree crevices, muddy hollows, and empty rodent holes. Ladybugs, fish, butterflies, lizards, and the yellow-bellied marmot are featured. Each spread depicts two views of the resting animal. Gentle watercolor scenes include a small black-and-white page that resembles a guidebook entry, which offers a sketch of the animal, its name, and brief facts. Readers learn that scientists have recently given more attention to the study of estivation. End material offers more details about each animal. Author and illustrator notes, a bibliography, and a substantial list of print and online resources are included. VERDICT A well-crafted and attractive text for animal fans, and a suitable introduction to the scientific concept of estivation.—Margaret Bush, Simmons Coll., Boston