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Draft:Mammal (rewrite)

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Mammals are vertebrate tetrapods of the class Mammalia. They are synapsids, as opposed to birds and other reptiles, which are sauropsids. They are named after the mammary glands, which mammals use to feed their young via lactation.[1] Other traits that distinguish them from sauropsids are the presence of fur, a neocortex in their brain, and three middle ear bones. As of 2018, there are around 6,400 known extant mammal species.[2]

Traits[edit]

Mammary glands[edit]

Fur[edit]

Neocortex[edit]

Middle ear bones[edit]

Types of mammals[edit]

Protomammals/stem mammals[edit]

See the main article on this topic: Synapsid

Monotremes[edit]

Marsupials[edit]

Placental mammals[edit]

Atlantogenata[edit]

Xenarthra[edit]

Armadillos, sloths, anteaters

Afrotheria[edit]

Aardvarks, elephant shrews, hyraxes, elephants, manatees, etc.

Boreoeutheria[edit]

Euarchontoglires[edit]

Rodents, lagomorphs, primates, etc.

Laurasiatheria[edit]

Hedgehogs, bats, ungulates, pangolins, carnivores, etc.

Notes[edit]

References[edit]

  1. The Evolution of Lactation in Mammalian Species, Olav T. Oftedal, Nestle Nutr Inst Workshop Ser. 2020;94:1-10 doi: 10.1159/000505577 Epub 10 Mar 20 20 PMID: 32155641
  2. How many species of mammals are there?, Nathan Upham, Journal of Mammalogy 99 1-14 10.1093/jmammal/gyx147