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Thyreophorans
Thyreophora ("shield bearers", often known simply as "armored dinosaurs") is a group of Armour (zoology), armored ornithischian dinosaurs that lived from the Early Jurassic until the end of the Cretaceous. Thyreophorans are characterized by the presence of body armor lined up in longitudinal rows along the body. Primitive forms had simple, low, keeled scutes or osteoderms, whereas more derived forms developed more elaborate structures including spikes and plates. Most thyreophorans were Herbivore, herbivorous and had relatively small brains for their body size. Thyreophora includes two major subgroups, Ankylosauria and Stegosauria. In both clades, the forelimbs were much shorter than the hindlimbs, particularly in stegosaurs. Thyreophora has been defined as the group consisting of all species more closely related to ''Ankylosaurus'' and ''Stegosaurus'' than to ''Iguanodon'' and ''Triceratops''. It is the sister group of Cerapoda within Genasauria. Characteristics Members of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Jurassic
The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic–Jurassic extinction event, 201.3 Ma (million years ago), and ends at the start of the Middle Jurassic 174.7 ±0.8 Ma. Certain rocks of marine origin of this age in Europe are called "Lias Group, Lias" and that name was used for the period, as well, in 19th-century geology. In southern Germany rocks of this age are called Black Jurassic. Origin of the name Lias There are two possible origins for the name Lias: the first reason is it was taken by a geologist from an England, English quarryman's dialect pronunciation of the word "layers"; secondly, sloops from north Cornwall, Cornish ports such as Bude would sail across the Bristol Channel to the Vale of Glamorgan to load up with rock from coastal limestone quarries (lias and Carbonif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
