Ammonites are used as index fossils for this period in which reptiles dominated the vertebrates, and which featured ferns, ginkgos, conifers, brachiopods, bivalves, and echinoids.
During this geologic period the first flying reptiles, the pterosaurs, appears, as did Archaeopteryx, the first primitive bird. Ammonites are used as index fossils for this period in which reptiles dominated the vertebrates, and which featured ferns, ginkgos, conifers, brachiopods, bivalves, and echinoids. Named in 1829 by A. Brongniart for a mountain range on the French-Swiss border, it extended from 190 to 139 million years ago. FTP, what is this period of the Mesozoic era between the Triassic and Cretaceous Periods?
During this geologic period the first flying reptiles, the pterosaurs, appears, as did Archaeopteryx, the first primitive bird.
Jurassic Period