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The Gobiconodonta are a group of extinct mammals known from the Middle Jurassic (klameliids)〔 to Early Cretaceous. ==Biology== Like many other non-therian mammals, gobiconodonts retained classical mammalian synapomorphies like epipubic bones (and likely the associated reproductive constrictions), venomous spurs and sprawling limbs. However, the forelimb and shoulder anatomy of at least some species like ''Jeholodens'' are similar to those of therian mammals, though the hindlimbs remain more conservative.〔 Some information on gobiconodont soft-tissues can be seen in ''Spinolestes'', which was very well preserved, showing evidence of fur and internal organs. ''Spinolestes'' shows hair similar to that of modern mammals, with compound hair follicles with primary and secondary hair, even preserving traces of a pore infection. It also possesses a clear thoracic diaphragm like modern mammals, as well as spines, dermal scutes and an ossified Meckel's cartilage.〔 〕 The gobiconodont triconodont dentition has no analogue among living mammals, so comparisons are difficult. However, its clear that most if not all gobiconodonts were primarily carnivorous, given the presence of long, sharp canines, premolars with trenchant main cusps that were well suited to grasp and pierce prey, strong development of the madibular abductor musculature, bone crushing ability in at least some species and several other features.〔 Gobiconodonts are often among the largest mammals in Mesozoic faunal assemblages, displaying a broad size range from small shrew-like insectivores to large forms like ''Repenomamus'' and ''Gobiconodon''. They were among the first mammals to be specialised for vertebrate prey, and likely occupied the highest trophic levels among mammals in their faunal communities. Several forms like ''Gobiconodon'' and ''Repenomamus'' show evidence of scavenging, being among the few Mesozoic mammals to have significantly exploited that.〔 At least in carnivorous niches, gobiconodonts were probably replaced by deltatheroidean metatherians, which are the dominant carnivorous mammals in Late Cretaceous faunal assemblages. At least ''Spinolestes'' had xenarthrous vertebrae and osseous scutes, convergent to those of modern xenarthrans and to a lesser extent the hero shrew.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gobiconodonta」の詳細全文を読む スポンサード リンク
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