Pterosaurs, the prehistoric flying reptiles (some ""smaller than sparrows,"" some ""bigger than airplanes"") are usually classed with dinosaurs at this level, but treated separately here. Which allows Kaufman both to consider generally how (and why) their wings might have evolved from ""flaps of skin"" and how they worked in soaring and to describe, in turn, Pteranadon, Rhamphorhynchus, and a few other prominent pterosaurs. The result is a sound, inquiring introduction for young scientists who want more than the usual tour guide approach.