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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Selected References
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- Alvarez L. W., Alvarez W., Asaro F., Michel H. V. Extraterrestrial cause for the cretaceous-tertiary extinction. Science. 1980 Jun 6;208(4448):1095–1108. doi: 10.1126/science.208.4448.1095. [DOI] [PubMed] [Google Scholar]
- Alvarez W., Asaro F., Michel H. V., Alvarez L. W. Iridium anomaly approximately synchronous with terminal eocene extinctions. Science. 1982 May 21;216(4548):886–888. doi: 10.1126/science.216.4548.886. [DOI] [PubMed] [Google Scholar]
- Dalrymple G. B. Geologic time: a geologic time scale. Science. 1983 Sep 2;221(4614):944–945. doi: 10.1126/science.221.4614.944. [DOI] [PubMed] [Google Scholar]
- Ganapathy R. Evidence for a major meteorite impact on the Earth 34 million years ago: implication for eocene extinctions. Science. 1982 May 21;216(4548):885–886. doi: 10.1126/science.216.4548.885. [DOI] [PubMed] [Google Scholar]
- Raup D. M., Sepkoski J. J., Jr Mass extinctions in the marine fossil record. Science. 1982 Mar 19;215(4539):1501–1503. doi: 10.1126/science.215.4539.1501. [DOI] [PubMed] [Google Scholar]
- Raup D. M. Size of the permo-triassic bottleneck and its evolutionary implications. Science. 1979 Oct 12;206(4415):217–218. doi: 10.1126/science.206.4415.217. [DOI] [PubMed] [Google Scholar]