The Pelvis and Femur of Ardipithecus ramidus: The Emergence of Upright Walking

@article{Lovejoy2009ThePA,
  title={The Pelvis and Femur of Ardipithecus ramidus: The Emergence of Upright Walking},
  author={C. Owen Lovejoy and Gen Suwa and Linda B. Spurlock and Berhane Abrha Asfaw and Tim D. White},
  journal={Science},
  year={2009},
  volume={326},
  pages={71 - 71e6}
}
The femur and pelvis of Ardipithecus ramidus have characters indicative of both upright bipedal walking and movement in trees. Consequently, bipedality in Ar. ramidus was more primitive than in later Australopithecus. Compared with monkeys and Early Miocene apes such as Proconsul, the ilium in Ar. ramidus is mediolaterally expanded, and its sacroiliac joint is located more posteriorly. These changes are shared with some Middle and Late Miocene apes as well as with African apes and later… 

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