How can the tracks of dinosaurs best be interpreted and used to reconstruct them? In many Mesozoic sedimentary rock formations, fossilized footprints of bipedal, three-toed (tridactyl) dinosaurs are preserved in huge numbers, often with few or no skeletons. Such tracks sometimes provide the only clues to the former presence of dinosaurs, but their interpretation can be challenging: How different in size and shape can footprints be and yet have been made by the same kind of dinosaur? How similar can they be and yet have been made by different kinds of dinosaurs? To what extent can tridactyl dinosaur footprints serve as proxies for the biodiversity of their makers?
Profusely illustrated and meticulously researched, Noah's Ravens quantitatively explores a variety of approaches to interpreting the tracks, carefully examining within-species and across-species variability in foot and footprint shape in nonavian dinosaurs and their close living relatives. The results help decipher one of the world's most important assemblages of fossil dinosaur tracks, found in sedimentary rocks deposited in ancient rift valleys of eastern North America. Those often beautifully preserved tracks were among the first studied by palaeontologists, and they were initially interpreted as having been made by big birds – one of which was jokingly identified as Noah's legendary raven.
1. Introduction: Noah's Ravens
2. Intraspecific and Interspecific Variability in Pedal Phalangeal and Digital Dimensions and Proportions in Non-Avian Dinosaurs, Birds, and Crocodylians
3. Pedal Shape and Phylogenetic Relationships
4. Toe Tapering Profiles in Non-Avian Dinosaurs and Ground Birds
5. Ontogenetic and Across-Species Trends in Hindfoot and Hindlimb Proportions
6. Intraspecific Variability in Pedal Size and Shape in Alligator mississippiensis
7. Footprints of the Emu (Dromaius novaehollandiae) and Other Ground Birds
8. Summing Up the Comparative Analyses
9. Noah's Ravens: Interpreting the Makers of Tridactyl Dinosaur Footprints of the Newark Supergroup, Early Jurassic, Eastern North America
10. Final Thoughts
James O. Farlow is Emeritus Professor of Geology at Indiana-Purdue University, Fort Wayne. He is the author of The Complete Dinosaur, Second Edition.