Eutheria (Greek: "true beasts") are a group of mammals consisting of placental mammals plus all extinct mammals that are more closely related to living placentals (such as humans) than to living marsupials (such as kangaroos). They are distinguished from non-eutherians by various features of the feet, ankles, jaws and teeth. One of the major differences between placental and non-placental eutherians is that placentals lack epipubic bones, which a...
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Eutheria (Greek: "true beasts") are a group of mammals consisting of placental mammals plus all extinct mammals that are more closely related to living placentals (such as humans) than to living marsupials (such as kangaroos). They are distinguished from non-eutherians by various features of the feet, ankles, jaws and teeth. One of the major differences between placental and non-placental eutherians is that placentals lack epipubic bones, which are present in all non-placental fossil and living mammals.
The earliest known fossil eutherian, Eomaia was found in Asia and is dated to the Early Cretaceous period, about 125 million years ago.
Eutherians are a group of mammals consisting of placental mammals plus all extinct mammals that are more closely related to living placentals (such as humans) than to living marsupials (such as kangaroos).
There are no living non-placental eutherians, and so knowledge of their synapomorphies ("defining features") is entirely based on a few fossils –...
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