mammal wiki:
>Subclass Multituberculata (extinct)PlagiaulacidaCimolodontaSubclass Palaeoryctoides (extinct)Subclass Triconodonta (extinct)Subclass Eutheria (includes extinct ancestors)/Placentalia (excludes extinct ancestors)AfrosoricidaArtiodactylaCarnivoraCetaceaChiropteraCimolesta (extinct)Creodonta (extinct)Condylarthra (extinct)DermopteraDesmostylia (extinct)Embrithopoda (extinct)HyracoideaInsectivoraLagomorphaLitopterna (extinct)MacroscelideaMesonychia (extinct)Notoungulata (extinct)PerissodactylaPholidotaPlesiadapiformes (extinct)PrimatesProboscideaRodentiaScandentiaSireniaTaeniodonta (extinct)Tillodontia (extinct)TubulidentataXenarthraSubclass MarsupialiaDasyuromorphiaDidelphimorphiaDiprotodontiaMicrobiotheriaNotoryctemorphiaPaucituberculataPeramelemorphiaSubclass MonotremataMonotremata The mammals are the class of vertebrate animals characterized by the presence of mammary glands, which in females produce milk for the nourishment of young; the presence of hair or fur; and which have endothermic or "warm-blooded" bodies. The brain regulates endothermic and circulatory systems, including a four-chambered heart. Mammals encompass some 5500 species, distributed in about 1200 genera, 152 families and up to 46 orders, though this varies depending on the classification scheme adopted.
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