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Dinosaur Taxonomy
Dinosaur classification began in 1842 when Sir Richard Owen placed ''Iguanodon'', ''Megalosaurus'', and ''Hylaeosaurus'' in "a distinct tribe or suborder of Saurian Reptiles, for which I would propose the name of Dinosauria." In 1887 and 1888 Harry Seeley divided dinosaurs into the two orders Saurischia and Ornithischia, based on their hip structure. These divisions have proved remarkably enduring, even through several seismic changes in the Taxonomy (biology), taxonomy of dinosaurs. The largest change was prompted by entomologist Willi Hennig's work in the 1950s, which evolved into modern cladistics. For specimens known only from fossils, the rigorous analysis of synapomorphy, characters to determine evolutionary relationships between different groups of animals (''clades'') proved incredibly useful. As computer-based cladistics matured in the 1990s, paleontology, paleontologists were among the first zoology, zoologists to broadly adopt the system. Progressive scrutiny and work ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution Of Dinosaurs EN
Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation. The scientific theory of evolution by natural selection was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace, in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book ''On the Origin of Species''. Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) phenotypic variatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
