Dual origin of tribosphenic mammals

@article{Luo2001DualOO,
  title={Dual origin of tribosphenic mammals},
  author={Zhe‐Xi Luo and Richard. Cifelli and Zofia Kielan-Jaworowska},
  journal={Nature},
  year={2001},
  volume={409},
  pages={53-57}
}
Marsupials, placentals and their close therian relatives possess complex (tribosphenic) molars that are capable of versatile occlusal functions. This functional complex is widely thought to be a key to the early diversification and evolutionary success of extant therians and their close relatives (tribosphenidans). Long thought to have arisen on northern continents, tribosphenic mammals have recently been reported from southern landmasses. The great age and advanced morphology of these new… 
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240 Citations

The Gondwanan Origin of Tribosphenida (Mammalia)

Abstract A review of the Southern Hemisphere Mesozoic tribosphenic mammal fossil record supports the hypothesis that Tribosphenida arose in the Southern Hemisphere during the Early Jurassic, around…

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Marsupial and monotreme evolution and biogeography

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The earliest known eutherian mammal

The skeleton of a eutherian (placental) mammal found in northeastern China has limb and foot features that are known only from scansorial and arboreal extant mammals, in contrast to the terrestrial or cursorial features of other Cretaceous eutherians.

A Jurassic eutherian mammal and divergence of marsupials and placentals

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