Hostname: page-component-7c8c6479df-94d59 Total loading time: 0 Render date: 2024-03-27T15:02:10.407Z Has data issue: false hasContentIssue false

Calibrating the Ordovician Radiation of marine life: implications for Phanerozoic diversity trends

Published online by Cambridge University Press:  14 July 2015

Arnold I. Miller
Affiliation:
Department of Geology (ML 13), University of Cincinnati, Cincinnati, Ohio 45221-0013
Mike Foote
Affiliation:
Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, Illinois 60637

Abstract

It has long been suspected that trends in global marine biodiversity calibrated for the Phanerozoic may be affected by sampling problems. However, this possibility has not been evaluated definitively, and raw diversity trends are generally accepted at face value in macroevolutionary investigations. Here, we analyze a global-scale sample of fossil occurrences that allows us to determine directly the effects of sample size on the calibration of what is generally thought to be among the most significant global biodiversity increases in the history of life: the Ordovician Radiation. Utilizing a composite database that includes trilobites, brachiopods, and three classes of molluscs, we conduct rarefaction analyses to demonstrate that the diversification trajectory for the Radiation was considerably different than suggested by raw diversity time-series. Our analyses suggest that a substantial portion of the increase recognized in raw diversity depictions for the last three Ordovician epochs (the Llandeilian, Caradocian, and Ashgillian) is a consequence of increased sample size of the preserved and catalogued fossil record. We also use biometric data for a global sample of Ordovician trilobites, along with methods of measuring morphological diversity that are not biased by sample size, to show that morphological diversification in this major clade had leveled off by the Llanvirnian. The discordance between raw diversity depictions and more robust taxonomic and morphological diversity metrics suggests that sampling effects may strongly influence our perception of biodiversity trends throughout the Phanerozoic.

Type
Articles
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Bambach, R. K. 1977. Species richness in marine benthic habitats through the Phanerozoic. Paleobiology 3:152167.CrossRefGoogle Scholar
Benton, M. J. 1993. The Fossil Record 2. Chapman and Hall, London.Google Scholar
Benton, M. J. 1995. Diversification and extinction in the history of life. Science 268:5258.CrossRefGoogle ScholarPubMed
Boucot, A. J. 1990. Phanerozoic extinctions: how similar are they to each other? pp. 530In Kauffman, E. G. and Walliser, O. H., eds. Extinction events in earth history. Springer, Berlin.CrossRefGoogle Scholar
Briggs, D. E. G., Fortey, R. A., and Wills, M. A. 1992. Morphological disparity in the Cambrian. Science 256:16701673.CrossRefGoogle ScholarPubMed
Erwin, D. H. 1993. The great Paleozoic crisis. Columbia University Press, New York.Google Scholar
Foote, M. 1991. Morphological patterns of diversification: examples from trilobites. Palaeontology 34:461485.Google Scholar
Foote, M. 1992. Rarefaction analysis of morphological and taxonomic diversity. Paleobiology 18:116.CrossRefGoogle Scholar
Foote, M. 1993. Discordance and concordance between morphological and taxonomic diversity. Paleobiology 19:185204.CrossRefGoogle Scholar
Harland, W. B., Armstrong, R. L., Cox, A. V., Craig, L. E., Smith, A. G., and Smith, D. G. 1990. A geologic time scale 1989. Cambridge University Press, Cambridge.Google Scholar
Hurlbert, S. H. 1971. The nonconcept of species diversity: a critique and alternative parameters. Ecology 52:577586.CrossRefGoogle ScholarPubMed
Miller, A. I., and Mao, S. 1995. Association of orogenic activity with the Ordovician radiation of marine life. Geology 23:305308.2.3.CO;2>CrossRefGoogle ScholarPubMed
Raup, D. M. 1975. Taxonomic diversity estimation using rarefaction. Paleobiology 1:333342.CrossRefGoogle Scholar
Raup, D. M. 1976a. Species diversity in the Phanerozoic: a tabulation. Paleobiology 2:279288.CrossRefGoogle Scholar
Raup, D. M. 1976b. Species diversity in the Phanerozoic: an interpretation. Paleobiology 2:289297.CrossRefGoogle Scholar
Raup, D. M. 1979. Biases in the fossil record of species and genera. Bulletin of the Carnegie Museum of Natural History 13:8591.Google Scholar
Sepkoski, J. J. Jr. 1981. A factor analytic description of the marine fossil record. Paleobiology 7:3653.CrossRefGoogle Scholar
Sepkoski, J. J. Jr. 1992. A compendium of fossil marine animal families, 2d. ed. Milwaukee Public Museum Contributions in Biology and Geology 83:1156.Google Scholar
Sepkoski, J. J. Jr. 1993. Ten years in the library: new data confirm paleontological patterns. Paleobiology 19:4351.CrossRefGoogle ScholarPubMed
Sepkoski, J. J. Jr. 1995. The Ordovician Radiations: diversification and extinction shown by global genus-level taxonomic data. pp. 393396In Cooper, J. D., Droser, M. L., and Finney, S. C., eds. Ordovician odyssey: short papers for the Seventh International Symposium on the Ordovician System. Pacific Section of the Society for Sedimentary Geology, Fullerton, Calif.Google Scholar
Sepkoski, J. J. Jr., Bambach, R. K., Raup, D. M., and Valentine, J. W. 1981. Phanerozoic marine diversity and the fossil record. Nature 293:435437.CrossRefGoogle Scholar
Signor, P. W. 1990. The geologic history of diversity. Annual Review of Ecology and Systematics 21:509539.CrossRefGoogle Scholar
Van Valen, L. 1974. Multivariate structural statistics in natural history. Journal of Theoretical Biology 45:235247.CrossRefGoogle ScholarPubMed
Wills, M. A., Briggs, D. E. G., and Fortey, R. A. 1994. Disparity as an evolutionary index: a comparison of Cambrian and Recent arthropods. Paleobiology 20:93130.CrossRefGoogle Scholar