What is Eomaia?
{{italictitle}} {{Taxobox | name = ''Eomaia'' | fossil_range = [[Lower Cretaceous]], 125 mya | image = Eomaia scansoria.JPG | image_width = 250px | image_caption = ''Eomaia'' | regnum = [[Animal]]ia | phylum = [[Chordata]] | classis = [[Mammal]]ia | subclassis = [[Theria]] | infraclassis = [[Eutheria]] | genus = '''''Eomaia''''' | genus_authority = Ji ''et al.'', 2002 | subdivision_ranks = [[Species]] | subdivision = * '''''E. scansoria''''' <small>Ji ''et al.'', 2002 ([[Type species|type]])</small> }} [[Image:Eomaia NT.jpg|thumb|right|Restoration]] '''''Eomaia''''' ('dawn mother') is an early [[fossil]] [[eutheria]]n [[mammal]]. It is exceptionally well-preserved for a 125 million-year-old specimen. It was discovered in rocks of the [[Yixian Formation]], [[Liaoning]] Province, [[China]]. These [[strata|stratas]] date from the Late Jurassic to the Cretaceous about 125 million years ago (mya).<ref name=Ji>{{cite journal | author=Ji Q. |display-authors = etal | title=The earliest known eutherian mammal | journal=Nature | volume=416 | pages=816–822 | date=2002 | doi=10.1038/416816a | url=http://www.nature.com/nature/journal/v416/n6883/full/416816a.html | accessdate=2008-09-24 | pmid=11976675 | issue=6883 |s2cid = 4330626 }}</ref> The fossil is {{convert|10|cm|in}} in length and virtually complete. It weighed between {{convert|20|-|25|g|oz}}. Although the fossil's skull is squashed flat, its teeth, tiny foot bones, cartilages and even its fur are visible.<ref name=Ji/> ''Eomaia'' is a [[eutheria]]n. The eutherians are the [[placental mammal]]s plus some extinct [[mammal]]s which had not developed a [[placenta]]. What distinguishes the Eutheria from [[metatheria]]ns, a group that includes modern [[marsupial]]s, are various features of the feet, jaws and teeth.<ref name=Ji/> However ''Eomaia'' is not a true placental mammal as it lacks some features that are specific to placentals. ''Eomaia'' has: *variations in the shin and ankles.<ref name=Ji/> *an ancestral eutherian [[dental formula]].<ref name=Ji/><ref name