Ultrasonic hearing and echolocation in the earliest toothed whales.
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ABSTRACT:
SUBMITTER: Park T
PROVIDER: S-EPMC4881348 | biostudies-literature | 2016 Apr
REPOSITORIES: biostudies-literature
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Ultrasonic hearing and echolocation in the earliest toothed whales.
Park Travis T Fitzgerald Erich M G EM Evans Alistair R AR
Biology letters 20160401 4
The evolution of biosonar (production of high-frequency sound and reception of its echo) was a key innovation of toothed whales and dolphins (Odontoceti) that facilitated phylogenetic diversification and rise to ecological predominance. Yet exactly when high-frequency hearing first evolved in odontocete history remains a fundamental question in cetacean biology. Here, we show that archaic odontocetes had a cochlea specialized for sensing high-frequency sound, as exemplified by an Oligocene xenor ...[more]
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