(Ji, Q. et al., 2002)

    Eomaia scansoria is a shrew-sized insectivore, a fast little predator of the spiny invertebrates that scuttle about the forest floor and among the branches of the trees.  E. scansoria is well-equipped to pursue its prey, possessing nimble clawed paws, and an array of needle-sharp teeth.  In fact, this little mammal is an adept climber, and spends much of its time in the trees.

  E. scansoria is the earliest known of the eutherians (a group that will include the great majority of mammalian species by the beginning of the Cenozoic).  However, this 25-gram, shrew-like creature can be distinguished from all post-Creataceous eutherians by the fact that it possesses epipubes, a pair of bones attached to the hips that are usually associated with the pouch of a marsupial.  E. scansoria's hips are too narrow to allow fully-developed young to pass through them, and the babies are born half-developed, little more than mobile embryos that then must find their own way to their mother's pouch, where they will continue to grow until they can leave and fend for themselves.  This entire arrangement is quite reminiscent of a marsupial, and yet E. scansoria is more closely related to the placental mammals, possessing the diagnostic teeth of this group.

    The kin of E. scansoria may be destined for greatness, but this particular species is only one of many small, furry creatures running about in early Cretaceous China.  Aside from a few like E. scansoria, most of these creatures represent clades that have no future past the end of the Cretaceous.  In fact, although the mammals of the Cretaceous are restricted to only a few niches by the more flamboyant dinosaurs, they actually exist in an astonishing diversity that will never be matched in the post-Cretaceous world.

Thanks to Ray Stanford for telling me the mass of this "little animal".
Other sites containing pertinent information:

• Carnegie Museum's Eomaiapage (with pictures, although the text is dumbed-down)
• Trevor Dykes's Eutheria internet directory Eomaia (very nice information, if few pictures)
• National Geographic's Eomaia article
• Dinosaurier.org's Eomaia (the text is German, but the page includes a very good skeletal reconstruction)
• The Evolution Papers' Eomaia (same pic as above, English text)
• Sinofossa's Eomaia
• Boban Filipovic's Sinosauropteryx and Eomaia
• Wikipedia's Eomaia article (the text is clunky, but good taxonomy)

© Daniel Bensen 2002
Watercolor, pen, and Adobe Photoshop
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