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Genomic versus morphologic rates of evolution: influence of morphologic complexity

Published online by Cambridge University Press:  08 April 2016

Thomas J. M. Schopf
Affiliation:
Dept. Geophys. Sci., Univ. Chicago, Chicago, Ill., 60637
David M. Raup
Affiliation:
Dept. Geol. Sci., Univ. Rochester, Rochester, New York, 14627
Stephen Jay Gould
Affiliation:
Dept. Geology, Harvard Univ., Cambridge, Mass., 02138
Daniel S. Simberloff
Affiliation:
Florida State Univ., Tallahassee, Florida, 32306

Abstract

The degree of perceived taxonomic change in various lineages may be directly related to their general morphologic complexity: more complex forms appear to change more rapidly. “Rates of evolution” as customarily reported by paleontologists may therefore be a poor indication of evolutionary changes in the underlying genome. Two approaches were used to examine this problem. (1) We have estimated the degree of morphologic complexity by using the number of descriptive terms per genus, and per family, for 12 major groups of animals. Three general levels of complexity occur: (i) gastropods, bivalves and ectoprocts have relatively few terms; (ii) echinoids, foraminiferans, ostracodes, nautiloids, corals, trilobites, and brachiopods have an intermediate number of terms; (iii) mammals and ammonoids appear to have a relatively large number of terms. These 3 levels of complexity also increase in rate of taxonomic turnover; i.e., an increasing rate of evolution. (2) Using a cluster analysis based on morphologic similarity, we grouped 200 lineages of a computer-generated phylogenetic sequence according to 4 phenetic bases: 3, 5, 10 and 20 morphologic traits. Groups based on a few characters are longer lived and are commonly polyphyletic in comparison with groups based on many characters. In both the real world and the computer simulation, the bias of differential morphologic complexity may account for the observation that “only complicated animals evolve.” Most paleontologic studies of the “rate of evolution” may tell us more about morphologic complexity than about evolutionary rates of genomes.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Boucot, A. J. 1974. Why ‘Communities’?: Comment. Geology. 2:204.Google Scholar
Durazzi, J. T., and Stehli, F. G. 1972. Average generic age, the planetary temperature gradient, and pole location. Syst. Zool. 21:384389.CrossRefGoogle Scholar
Eldredge, N., and Gould, S. J. 1972. Punctuated equilibria: an alternative to phyletic gradualism. In, Schopf, T. J. M., ed. Models in Paleobiology, Freeman, Cooper. San Francisco. p. 82115.Google Scholar
Frick, C. 1937. Horned ruminants of North America. Bull. American Mus. Nat. Hist. 69:1669.Google Scholar
Hecht, M. K. 1965. The role of natural selection and evolutionary rates in the origin of higher levels of organization. Syst. Zool. 14:301317.Google Scholar
King, M-C., and Wilson, A. C. 1975. Evolution at two levels: Molecular similarities and biological differences between humans and chimpanzees. Science: (In Press).Google Scholar
Larwood, G. P., Medd, A. W., Owen, D. E., and Tavener-Smith, R. 1967. Bryozoa. In, Harland, W. B., et al., eds., The Fossil Record. Geol. Soc. London. London. p. 379395.Google Scholar
Lewontin, R. C. 1974. The Genetic Basis of Evolutionary Change. 346 pp. Columbia Univ. Press. New York, N. Y.Google Scholar
Loeblich, A. R. Jr., and Tappan, H. 1964. Foraminiferal facts, fallacies, and frontiers. Geol. Soc. America Bull. 75:367392.Google Scholar
Maxson, L. R., and Wilson, A. C. 1974. Convergent morphological evolution detected by studying proteins of tree frogs in the Hyla eximia species group. Science. 185:6668.CrossRefGoogle ScholarPubMed
Raup, D. M. 1975. Taxonomic Survivorship Curves and Van Valen's Law. Paleobiology 1:8296.Google Scholar
Raup, D. M., and Gould, S. J. 1974. Stochastic simulation and the evolution of morphology—towards a nomothetic paleontology. Syst. Zool. 23:305322.Google 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. Jour. Geology. 81:525542.CrossRefGoogle Scholar
Romer, A. S. 1966. Vertebrate Paleontology. 468 pp. Univ. Chicago Press. Chicago, Illinois.Google Scholar
Schopf, T. J. M. 1974a. Permo-Triassic extinctions: relation to sea-floor spreading. Jour. Geology. 82:129143.CrossRefGoogle Scholar
Schopf, T. J. M. 1974b. Survey of genetic differentiation in a coastal zone invertebrate: the ectoproct Schizoporella errata. Bio. Bull. 145:7887.Google Scholar
Sepkoski, J. J. Jr., and Rex, M. A. 1974. Distribution of freshwater mussels: coastal rivers as biogeographic islands. Syst. Zool. 23:165188.Google Scholar
Simberloff, D. S. 1974. Permo-Triassic extinctions: effects of area on biotic equilibrium. Jour. Geology. 82:267274.Google Scholar
Simpson, G. G. 1953. The Major Features of Evolution. 434 pp. Columbia Univ. Press. New York, N. Y.CrossRefGoogle Scholar
Stanley, S. M. 1973. Effects of competition on rates of evolution with special reference to bivalve mollusks and mammals. Syst. Zool. 22:486506.Google Scholar
Stehli, F. G., and Wells, J. W. 1971. Diversity and age patterns in hermatypic corals. Syst. Zool. 20:115126.Google Scholar
Stehli, F. G., Douglas, R. G., and Kafescioglu, I. A. 1972. Models for the evolution of planktonic Foraminifera. In, Schopf, T. J. M., ed. Models in Paleobiology. Freeman, Cooper. San Francisco. p. 116128.Google Scholar
Stehli, F. G., Douglas, R. G., and Newell, N. D. 1969. Generation and maintenance of gradients in taxonomic diversity. Science. 164:947949.Google Scholar
Van Valen, L. 1973a. Are categories in different phyla comparable? Taxon. 22:333373.Google Scholar
Van Valen, L. 1973b. A new evolutionary law. Evolutionary Theory. 1:130.Google Scholar
Wallace, D. G., King, M-C., and Wilson, A. C. 1973. Albumin differences among ranid frogs: taxonomic and phylogenetic implications. Systematic Zoology. 22:113.Google Scholar
Williams, A. 1957. Evolutionary rates of brachiopods. Geol. Mag. 94:201211.CrossRefGoogle Scholar
Wilson, E. O. 1955. A monographic revision of the ant genus Lasius. Bull. Mus. Comp. Zool. Harvard. 113:1204.Google Scholar