Vestibular evidence for the evolution of aquatic behaviour in early cetaceans

  title={Vestibular evidence for the evolution of aquatic behaviour in early cetaceans},
  author={Fred Spoor and Sunil Bajpai and S. Taseer Hussain and K Ravi Kumar and J. G. M. Thewissen},
Early cetaceans evolved from terrestrial quadrupeds to obligate swimmers, a change that is traditionally studied by functional analysis of the postcranial skeleton. Here we assess the evolution of cetacean locomotor behaviour from an independent perspective by looking at the semicircular canal system, one of the main sense organs involved in neural control of locomotion. Extant cetaceans are found to be unique in that their canal arc size, corrected for body mass, is approximately three times… 

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