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Where did the earliest marsupials originate according to fossil evidence?
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marsupial
Red kangaroo (Macropus rufus). The home range of this species spans much of Australia's interior, and it is the largest member of the family Macropodidae.
Fossil evidence indicates that marsupials originated in the New World. The oldest known marsupial fossils, dating back approximately 125 million years to the Cretaceous Period, have been discovered in both North America and China.1
While some early mammals like the extinct Ambondro possessed features such as tribosphenic dentitionâwhich is also found in the ancestors of marsupials and placental mammalsâthese specimens date to the Middle Jurassic and are distinct from the earliest true marsupials. Following their origin in the New World, ancestral marsupials eventually migrated to Australia via Antarctica and South America, where they later evolved into diverse forms in isolation.21