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Clams and brachiopods—ships that pass in the night

Published online by Cambridge University Press:  08 February 2016

Stephen Jay Gould  and
C. Bradford Calloway
Stephen Jay Gould
Affiliation:
Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138
C. Bradford Calloway
Affiliation:
Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138
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Abstract

The presumed geometry of clam and brachiopod clades (brachiopod declines matched closely by clam increases) has long served as primary data for the classic case of gradual replacement by competition in geological time. Agassiz invoked the geometric argument to assert the general superiority of clams, and it remains the standard textbook illustration today. Yet, like so many classic stories, it is not true. The supposed replacement of brachiopods by clams is not gradual and sequential. It is a product of one event: the Permian extinction (which affected brachiopods profoundly and clams relatively little). When Paleozoic and post-Paleozoic times are plotted separately, numbers of clam and brachiopod genera are positively correlated in each phase. Each group pursues its characteristic and different history in each phase—clams increasing, brachiopods holding their own. The Permian extinction simply reset the initial diversities. The two groups seem to track each other in each phase and a plot of brachiopod vs. clam residuals (each from their own within-phase regressions against time) yields significantly positive association. Some of this tracking may be an artifact of available rock volumes; we could, however, detect no effect of stage lengths. Passive extrapolation of microevolutionary theory into the vastness of geological time has often led paleontologists astray. Competitive interaction may rule in local populations, but differential response to mass extinctions (surely not a matter of conventional competition) may set the relative histories of large groups through geological time. Similarly, adaptive superiority in design cannot, in the usual sense of optimal engineering, have much to do with the macroevolutionary success of clams. The interesting question lies one step further back: what in the inherited Bauplan of a clam permits flexibility in design and why are other groups, however successful in their own domain, unable to alter their basic design.

Type
Articles
Information
Paleobiology , Volume 6 , Issue 4 , Fall 1980 , pp. 383 - 396
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Agassiz, L. 1857. Essay on Classification (reprinted 1962, Harvard Univ. Press, 268 pp.).Google Scholar
Ager, D. V. 1971. Space and time in brachiopod history. In: Middlemiss, F. A., Rawson, P. F., and Newall, G., eds. Faunal Provinces in Space and Time. Geol. J. Special Issue. 4:95–110.Google Scholar
Andrewartha, H. G. and Birch, L. C. 1954. The Distribution and Abundance of Animals. 782 pp. Univ. Chicago Press; Chicago, Illinois.Google Scholar
Bambach, R. K. 1977. Species richness in marine benthic habitats through the Phanerozoic. Paleobiology. 2:152–167.CrossRefGoogle Scholar
Bretsky, P. W. 1969. Evolution of Paleozoic benthic marine invertebrate communities. Palaeogeogr. Palaeoclimatol. Palaeoecol. 6:45–59.CrossRefGoogle Scholar
Brouwer, A. 1967. General Palaeontology. 216 pp. Univ. Chicago Press; Chicago, Illinois.Google Scholar
Cooper, G. A. and Grant, R. E. 1972–1977. Permian brachiopods of West Texas, I–VI. Smithsonian Contrib Paleontol. Nos. 14, 15, 19, 21, 24, and 32.Google Scholar
Ezekiel, M. and Fox, K. A. 1959. Methods of Correlation and Regression Analysis. 548 pp. John Wiley; New York.Google Scholar
Goldschmidt, R. 1940. The Material Basis of Evolution. 436 pp. Yale Univ. Press; New Haven, Connecticut.Google Scholar
Gould, S. J. and Eldredge, N. 1977. Punctuated equilibria: the tempo and mode of evolution reconsidered. Paleobiology. 3(2):115–151.CrossRefGoogle Scholar
Gould, S. J., Raup, D. M., Sepkoski, J. J. Jr., Schopf, T. J. M., and Simberloff, D. S. 1977. The shape of evolution: a comparison of real and random clades. Paleobiology. 3(1):23–40.CrossRefGoogle Scholar
Gregory, W. K. 1951. Evolution Emerging. 2 Vols. 736 and 1013 pp. Macmillan; New York.Google Scholar
Harland, W. B. et al. 1967. The Fossil Record. 827 pp. Geol. Soc.; London.Google Scholar
Harper, C. H. Jr. 1975. Standing diversity of fossil groups in successive intervals of geologic time: a new measure. J. Paleontol. 49:752–757.Google Scholar
Mayr, E. 1959. The emergence of evolutionary novelties. Reprinted in Mayr, E. 1976. Evolution and the Diversity of Life. pp. 88–113. Harvard Univ. Press; Cambridge, Massachusetts.Google Scholar
Raup, D. M. 1972. Taxonomic diversity during the Phanerozoic. Science. 177:1065–1071.CrossRefGoogle ScholarPubMed
Raup, D. M. 1978. Cohort analysis of generic survivorship. Paleobiology. 4:1–15.CrossRefGoogle Scholar
Raup, D. M. 1980. Size of the Permo-Triassic bottleneck and its evolutionary implications. Science. 206:217–218.CrossRefGoogle Scholar
Raup, D. M. and Gould, S. J. 1974. Stochastic simulation and evolution of morphology—towards a nomothetic paleontology. Syst. Zool. 23(3):305–322.CrossRefGoogle Scholar
Raup, D. M., Gould, S. J., Schopf, T. J. M., and Simberloff, D. S. 1973. Stochastic models of phylogeny and the evolution of diversity. J. Geol. 81(5):525–542.CrossRefGoogle Scholar
Roger, J. 1977. Paléoécologie. 170 pp. Masson; Paris.Google Scholar
Ronov, A. B. 1959. On the post-Precambrian geochemical history of the atmosphere and hydrosphere. Geochemistry. 5:493–506.Google Scholar
Ronov, A. B., Khain, V., Baluknovskiy, A. N., and Seslavinskiy, K. B. 1977. Changes in distribution, volumes, and rates of deposition of sedimentary and volcanogenic deposits during the Phanerozoic (within the present continents). Int. Geol. Rev. 19:1297–1304.CrossRefGoogle Scholar
Rudwick, M. J. S. 1970. Living and Fossil Brachiopods. 199 pp. Hutchinson and Co.; London.Google Scholar
Sepkoski, J. J. Jr. 1978. A kinetic model of Phanerozoic taxonomic diversity I. Analysis of marine orders. Paleobiology. 4(3):223–251.CrossRefGoogle Scholar
Sepkoski, J. J. Jr. 1979. A kinetic model of Phanerozoic diversity II. Paleobiology. 5(3):222–251.CrossRefGoogle Scholar
Shrock, R. R. and Twenhofel, W. H. 1953. Principles of Invertebrate Paleontology. 816 pp. McGraw-Hill; New York.Google Scholar
Simpson, G. G. 1953. Life of the Past. 198 pp. Yale Univ. Press; New Haven, Connecticut.Google Scholar
Stanley, S. M. 1968. Post-Paleozoic adaptive radiation of infaunal bivalve molluscs—a consequence of mantle fusion and siphon formation. J. Paleontol. 42:214–229.Google Scholar
Stanley, S. M. 1972. Functional morphology and evolution of byssally attached bivalve mollusks. J. Paleontol. 46:165–212.Google Scholar
Stanley, S. M. 1974. What has happened to the articulate brachiopods? Abstr. Geol. Soc. Am. Annu. Meeting, Miami Beach, Florida.Google Scholar
Stanley, S. M. 1975. Adaptive themes in the evolution of the Bivalvia (Mollusca). Annu. Rev. Earth Planet. Sci. 3:361–385.CrossRefGoogle Scholar
Stauffer, R. C., ed. 1975. Charles Darwin's Natural Selection. Being the Second Part of his Big Species Book Written From 1856–1858. 694 pp. Cambridge Univ. Press; New York.Google Scholar
Steele-Petrović, H. M. 1979. The physiological differences between articulate brachiopods and filter-feeding bivalves as a factor in the evolution of marine level-bottom communities.Google Scholar
Thomas, R. D. K. 1975. Functional morphology, ecology, and evolutionary conservatism in the Glycymerididae (Bivalvia). Paleontology. 18:217–254.Google Scholar
Thomas, R. D. K. 1976. Constraints of ligament growth, form and function on evolution in the Arcoida (Mollusca: Bivalvia). Paleobiology. 2:64–83.CrossRefGoogle Scholar
Thomas, R. D. K. 1978. Shell form and the ecological range of living and extinct Arcoida. Paleobiology. 4:181–194.CrossRefGoogle Scholar
Vermeij, G. J. 1973. Adaptation, versatility and evolution. Syst. Zool. 22:466–477.CrossRefGoogle Scholar
Yule, G. V. 1926. Why do we sometimes get nonsense-correlations between time series?—A study in sampling and the nature of time series. J. R. Stat. Soc. 89:1–64.CrossRefGoogle Scholar