Magnificent full dinosaur skeletons like Sue, the T. Rex specimen currently housed in Chicago’s Field Museum, have been invaluable to paleontologists in discovering how these reptilian behemoths moved and behaved many millions of years ago. Yet many dinosaur buffs may be surprised to learn just how little current information about these creatures is discovered in their bones. Instead much is learned via the little known field of ichnology, a branch of geology that studies animal burrows, tracks, trails, and feces. As veteran ichnologist Martin explains in this thorough overview of the CSI-like scientific discipline, particularly as it overlaps with paleontology, an astonishing number of features about dinosaur habits, diet, and even migration patterns can be gleaned from abundant “trace” fossils. Some recent, eye-opening discoveries include certain species’ penchant for building nests and, improbably, taking regular swims in rivers and lakes. Martin’s rigorous descriptions of his profession’s painstaking research techniques will probably not endear his work to mainstream audiences but paleontology and forensic science enthusiasts will undoubtedly find it fascinating.