An early Miocene extinction in pelagic sharks

  title={An early Miocene extinction in pelagic sharks},
  author={Elizabeth C. Sibert and Leah D. Rubin},
  pages={1105 - 1107}
Mysterious mass extinction The term “shark” inspires predictable images of stealthy and streamlined marine predators that are key components of modern ecosystems. Studying shark teeth buried in deep sea sediment, Sibert and Rubin reveal that current shark diversity is a small remnant of a much larger array of forms that were decimated by a previously unidentified major ocean extinction event (see the Perspective by Pimiento and Pyenson). The extinction led to a reduction in shark diversity by… 

Response to Comment on “An early Miocene extinction in pelagic sharks”

It is shown that species-level shark diversity would have to decrease by >90% to account for the observed >70% denticle extinction, implying that the early Miocene shark extinction was larger than previously recognized.

Comment on “An early Miocene extinction in pelagic sharks”

An early Miocene extinction in pelagic sharks is reported based on the loss of shark denticle diversity in two widely separated deep-sea sediment cores but it is asserted that the pattern observed is not a consequence of extinction but results from shifting species ranges induced by global current reorganization.

Comment on “An early Miocene extinction in pelagic sharks”

It is argued that Sibert and Rubin's interpretations of a previously unidentified, major extinction event of open-ocean sharks in the early Miocene are based on an experimental design that does not account for a considerable rise in the sedimentation rate coinciding with the proposed event, nor for intraspecific variation in denticle morphology.

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