“Types of Dinosaurs”: A Zoologist’s Field Guide to the Major Dinosaur Groups

1) What counts as a dinosaur (and what doesn’t)?“Dinosaur” is not a catch-all word for any big prehistoric reptile. Dinosaurs are a specific branch of archosaurs (the group that also includes crocodilians and birds) with a distinctive body plan—most famously, upright limbs held under the body ra...