Changes

This impressive concept book surveys changes in nature through lively photographs. With a simple, knowing style, Allen ( One, Two, Three -- Ah-Choo! ; Farley, Are You for Real? ) and Rotner study the growth and transformations of plants and animals. Piglets mature into large sows; fiddleheads uncurl into graceful ferns. ``All things go through changes,'' the author explains succinctly. In her first picture book, Rotner's photographs accompany the easily understood text: ``Spring blossoms yield summer fruit; in autumn, corn grows high.'' Juxtaposed photos of a speckled fawn and a grey-horned buck depict an animal's growth with the passage of time; pictures of a boy as he grows from infancy to preschool age show similar alterations. Readers will gain an important understanding of the many different faces of each living thing through this timely, engaging book. Ages 2-6. (Apr.)