A Jurassic mammaliaform and the earliest mammalian evolutionary adaptations

@article{Zhou2013AJM,
  title={A Jurassic mammaliaform and the earliest mammalian evolutionary adaptations},
  author={Chang-Fu Zhou and Shaoyuan Wu and Thomas Martin and Zhe‐Xi Luo},
  journal={Nature},
  year={2013},
  volume={500},
  pages={163-167}
}
The earliest evolution of mammals and origins of mammalian features can be traced to the mammaliaforms of the Triassic and Jurassic periods that are extinct relatives to living mammals. Here we describe a new fossil from the Middle Jurassic that has a mandibular middle ear, a gradational transition of thoracolumbar vertebrae and primitive ankle features, but highly derived molars with a high crown and multiple roots that are partially fused. The upper molars have longitudinal cusp rows that… 

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