Evidence for convergent evolution of ultrasonic hearing in toothed whales (Cetacea: Odontoceti)

  title={Evidence for convergent evolution of ultrasonic hearing in toothed whales (Cetacea: Odontoceti)},
  author={Rachel A. Racicot and Robert W. Boessenecker and Simon A. F. Darroch and Jonathan H Geisler},
  journal={Biology Letters},
Toothed whales (Cetacea: Odontoceti) are the most diverse group of modern cetaceans, originating during the Eocene/Oligocene transition approximately 38 Ma. All extant odontocetes echolocate; a single origin for this behaviour is supported by a unique facial source for ultrasonic vocalizations and a cochlea adapted for hearing the corresponding echoes. The craniofacial and inner ear morphology of Oligocene odontocetes support a rapid (less than 5 Myr) early evolution of echolocation. Although… 

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