Eutheria - Video Learning - WizScience.com

• published: 08 Sep 2015
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"Eutheria" is one of two mammalian clades with extant members that diverged in the Early Cretaceous or perhaps the Late Jurassic. The other is the Metatheria, which includes marsupials, most of whom accommodate their offspring in their mothers pouches. Except for the Virginia opossum, from North America, which is a metatherian, all mammals indigenous to Europe, Africa, Asia, and North America north of Mexico are eutherians. Extant eutherians, their last common ancestor, and all extinct descendants of that ancestor are placentals, in the group Placentalia. Eutherians are distinguished from noneutherians by various phenotypic traits of the feet, ankles, jaws and teeth. One of the major differences between placental and nonplacental eutherians is that placentals lack epipubic bones, which are present in all other fossil and living mammals . The oldest known eutherian species is "Juramaia sinensis", dated at from the Jurassic in China. Eutheria was named in 1872 by Theodore Gill; in 1880 Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia. Distinguishing features are: Eutheria contains several extinct genera as well as larger groups, many with complicated taxonomic histories still not fully undertood. Members of the Adapisoriculidae, Cimolesta and Leptictida have been previously placed within the out-dated placental group Insectivora, while Zhelestids have been considered primitive ungulates. However, more recent studies have suggested these enigmatic taxa represent stem group eutherians, more basal to Placentalia. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Eutheria, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.