The earliest known fully quadrupedal sirenian

@article{Domning2001TheEK,
  title={The earliest known fully quadrupedal sirenian},
  author={Daryl Domning},
  journal={Nature},
  year={2001},
  volume={413},
  pages={625-627}
}
  • D. Domning
  • Published 11 October 2001
  • Geography
  • Nature
Modern seacows (manatees and dugongs; Mammalia, Sirenia) are completely aquatic, with flipperlike forelimbs and no hindlimbs. Here I describe Eocene fossils from Jamaica that represent nearly the entire skeleton of a new genus and species of sirenian—the most primitive for which extensive postcranial remains are known. This animal was fully capable of locomotion on land, with four well-developed legs, a multivertebral sacrum, and a strong sacroiliac articulation that could support the weight of… 
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