Grallator variabilis, dinosaur track (negative) Iguanodon Eoraptor was found in the

Eoraptor was found in the same rock formation that yielded Herrerasaurus

The gas caused the crinoid to float and could probably be regulated to allow the crinoid to move up and down in the water column

Dromaeosaurus resembles the tyrannosaurs

an eel-like tail

rather than preying primarily upon eggs as had been traditionally thought

Grallator variabilis, dinosaur track (negative) Iguanodon Eoraptor was found in theThe study of fossilized footprints, Ichnology, has become an important branch of paleontology. Footprints are trace fossils. They are considered trace fossils because they contain no fossil material, only the impressions left by the animal which made them. It is often difficult to determine with certainty which animal made a given print and therefore they are usually attributed to a group rather than a specific animal. Grallator is an ichnogenus,