Information AboutTherapsid |
| CATEGORIES ABOUT THERAPSIDA | |
| therapsids | |
Therapsids, previously known as the " Mammal-like Reptile s", are an Order of Synapsid s. Traditionally, synapsids were referred to as Reptile s, however when the term is used Cladistically the Taxon also includes the Mammal s, which are descended from the Cynodont therapsids. Therapsids evolved from Sphenacodontia eupelycosaur group, they appeared Early Permian . Therapsids became the dominant land animals during the Middle Permian , and consisted of three major Clades , the Dinocephalia ns, the herbivorous Anomodont s, and the mostly carnivorous Theriodont s, with the carnivorous Biarmosuchia ns as a Paraphyletic assemblage of primitive forms. After a brief burst of evolutionary diversity, the dinocephalians died out in the later Middle Permian ( Guadalupian ), but the anomodont Dicynodont s and the theriodont Gorgonopsia ns and Therocephalia ns flourished, and were joined at the very end of the Permian by the first Cynodont s. Like all land animals, the therapsids were seriously affected by the End Permian Extinction Event , with the very successful gorgonopsians dying out altogether, and the remaining groups being represented by only one or two families of a few species each surviving into the Triassic . Of these, the dicynodonts, now represented by a single family of large stocky Herbivore s, the Kannemeyeridae , and the medium-sized cynodonts (including both carnivorous and herbivorous forms), flourished worldwide throughout the Early and Middle Triassic, but then died out across much of Pangea at the end of the Carnian (Late Triassic), although they continued for some time longer in the wet equatorial band and the south. Some exceptions were the yet still further derived Eucynodonts . At least three groups of them survived. # The extremely mammal-like family, Tritylodontidae , survived into the Early Cretaceous . # An extremely mammal-like family, Tritheledontidae , are unknown later than the Early Jurassic . # The third group, '' Morganucodon '' and similar animals, were Stem-mammals . TAXONOMY
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