| Although the fossilized remains of dinosaurs are fairly common, their footprints, called trace fossils, are only occasionally found. Such fossils began as footprints in soft mud or clay that eventually hardened in the hot sun. Following hardening these impressions were covered over with fresh mud, sand, or clay during floods and eventually fossilized. Careful examination of such fossilized tracks can reveal useful information about the biology and general movements of dinosaurs. |