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Cited by 974

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Periodicity of extinctions in the geologic past.

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Raup, D M, Sepkoski, J J·1984·Proceedings of the National Academy of Sciences

Abstract

The temporal distribution of the major extinctions over the past 250 million years has been investigated statistically using various forms of time series analysis. The analyzed record is based on variation in extinction intensity for fossil families of marine vertebrates, invertebrates, and protozoans and contains 12 extinction events. The 12 events show a statistically significant periodicity (P less than 0.01) with a mean interval between events of 26 million years. Two of the events coincide with extinctions that have been previously linked to meteorite impacts (terminal Cretaceous and Late Eocene). Although the causes of the periodicity are unknown, it is possible that they are related to extraterrestrial forces (solar, solar system, or galactic).

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Metadata

Authors
Raup, D. M., & Sepkoski, J. J.
Venue
Proceedings of the National Academy of Sciences
Published
1984-02
Volume
81
Issue
3
Pages
801-805
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2036995861
Cited by
974
References
0
FWCI
84.14
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Periodicity of extinctions in the geologic past. https://app.cochat.ai/papers/10.1073/pnas.81.3.801
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Raup, D. M., & Sepkoski, J. J. (1984). Periodicity of extinctions in the geologic past. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.81.3.801

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Bibliographic data: Semantic Scholar, OpenAlex, Crossref.

Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.