Whales originated from aquatic artiodactyls in the Eocene epoch of India

@article{Thewissen2007WhalesOF,
  title={Whales originated from aquatic artiodactyls in the Eocene epoch of India},
  author={J. G. M. Thewissen and Lisa Noelle Cooper and Mark T. Clementz and Sunil Bajpai and Brahma Nand Tiwari},
  journal={Nature},
  year={2007},
  volume={450},
  pages={1190-1194}
}
Although the first ten million years of whale evolution are documented by a remarkable series of fossil skeletons, the link to the ancestor of cetaceans has been missing. It was known that whales are related to even-toed ungulates (artiodactyls), but until now no artiodactyls were morphologically close to early whales. Here we show that the Eocene south Asian raoellid artiodactyls are the sister group to whales. The raoellid Indohyus is similar to whales, and unlike other artiodactyls, in the… 
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