Upside Down Babies

Willis and Reynolds, the team behind I'm Sure I Saw a Dinosaur and other stories, imagine a (gentle) global cataclysm that jumbles the natural order: "Once when the world tipped upside down,/ The earth went blue and the sky went brown./ All the baby animals tumbled out of bed/ And ended up with very funny moms instead." Willis's bouncy nursery-rhyme cadence propels readers through several funny fish-out-of-water scenarios that see a baby pig landing "ker-plonk in a parrot's nest," a baby lion howling "I want meat!" when offered grass by Mommy Cow, and mutual puzzlement on the parts of Mrs. Cheetah and Mrs. Sloth, who end up with each other's slow and speedy offspring. Reynolds's characteristically exuberant illustrations revel in the comedic possibilities, from a baby polar bear's dismay at being stuck in the desert with Mommy Camel to a mother owl's early morning shock when Baby Rooster starts crowing. A second out-of-the-blue occurrence sets things right, but Willis and Reynolds conclude with a punchline that will tickle any readers who already think of their younger siblings as being part ape. Ages 4%E2%80%939. (Mar.)