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Comment on "An early Miocene extinction in pelagic sharks"
I Feichtinger1, S Adnet2, G Cuny3
1Geological-Palaeontological Department, Natural History Museum Vienna, 1010 Vienna, Austria.
Science (New York, N.Y.)
|December 9, 2021
Summary
This study challenges the identification of a major early Miocene shark extinction event. The authors argue that increased sedimentation and variation in shark denticles were overlooked, invalidating the proposed extinction event.
Area of Science:
- Paleontology
- Marine Biology
- Geology
Background:
- A recent study proposed a major extinction event for open-ocean sharks in the early Miocene.
- This event was based on interpretations of fossil records.
Purpose of the Study:
- To re-evaluate the evidence for a major early Miocene shark extinction event.
- To identify potential flaws in the experimental design of the original study.
Main Methods:
- Analysis of fossil shark denticle morphology.
- Consideration of sedimentation rates during the early Miocene.
- Re-examination of the experimental design used in the Sibert and Rubin study.
Main Results:
- The original study's conclusions may be invalidated by overlooking increased sedimentation rates.
- Intraspecific variation in shark denticle morphology was not adequately accounted for.
- The proposed major extinction event is questioned based on these factors.
Conclusions:
- The interpretation of a major early Miocene shark extinction event requires re-evaluation.
- Sedimentation rates and intraspecific variation are critical factors in paleontological interpretations.
- Further research is needed to accurately assess shark population dynamics in the early Miocene.
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