Puffins and penguins may look funny sometimes, but they really aren't silly at all,"" says Gustafson in closing her five-page chapter on those particular burrowers--but her attempts to be cute can be silly. There's the ""calendar of the Wilson's Storm-Petrol,"" which consists of the following monthly entries: ""Gather at breeding grounds in the Antarctic. Lay one egg. Feed baby. Keep feeding baby. Feed baby some more. Leave baby. Fly. Fly. Fly. Fly. Fly. Fly to gather at breeding grounds in the Antarctic."" (Some of these entries have parenthetical elaborations, from one to seven lines in length, and some have none.) Then there is the chapter on the Fairy Prion's ""weird guests""--""prehistoric monsters"" called Tuataras who share their burrows. ""What do you suppose a baby Prion thinks each morning when a Tuatara slouches in? Would you leave your little sister with a three-eyed monster all day long?"" When not being silly, the book simply describes the lives and peculiarities of one burrowing bird after another. Significant biological concepts, when encountered, are not explained: Will elementary readers understand why, when the mother kingfisher comes through the tunnel entrance with food, ""the shadow makes the babies gape?"" Only at the end of the book does Gustafson make any general statements about the evolutionary background and advantages of burrowing. Till then, this is merely an aimless sampling of a seemingly arbitrary cross-section of creation.