Fossil Evidence for the Origin of Aquatic Locomotion in Archaeocete Whales

@article{Thewissen1994FossilEF,
  title={Fossil Evidence for the Origin of Aquatic Locomotion in Archaeocete Whales},
  author={J. G. M. Thewissen and S. Taseer Hussain and Muhammad Arif},
  journal={Science},
  year={1994},
  volume={263},
  pages={210 - 212}
}
Recent members of the order Cetacea (whales, dolphins, and porpoises) move in the water by vertical tail beats and cannot locomote on land. Their hindlimbs are not visible externally and the bones are reduced to one or a few splints that commonly lack joints. However, cetaceans originated from four-legged land mammals that used their limbs for locomotion and were probably apt runners. Because there are no relatively complete limbs for archaic archaeocete cetaceans, it is not known how the… 

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