Cretaceous Period Dinosaur Fossils Paleobiology Triassic Period Footprint Analysis Excavation Jurassic Period Cyanobacteria Fossils Footprints Dental Analysis Microfossils Sedimentary Rock Oldest Fossils Thylakoid Membranes Ancient Organisms Fossil Preservation Discovery Opal Fossils Marine Fossils Opalization Fossil Record Late Cretaceous Pterosaur Fossils Carboniferous Period Rock Identification Paleoecology