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Discordance and concordance between morphological and taxonomic diversity

Published online by Cambridge University Press:  08 February 2016

Mike Foote*
Affiliation:
Museum of Paleontology and Department of Geological Sciences, The University of Michigan, Ann Arbor, Michigan 48109

Abstract

Morphological and taxonomic diversity each provide insight into the expansion and contraction of major biological groups, while the nature of the relationship between these two aspects of diversity also has important implications for evolutionary mechanisms. In this paper, I compare morphological and taxonomic diversity within the classes Blastoidea and Trilobita, and within the trilobite clades Libristoma, Asaphina, Proetida, Phacopida, and Scutelluina. Blastoid morphology is quantified with homologous landmarks on the theca, and trilobite form is measured with a Fourier description of the cranidium. Morphological diversity is measured as the total variance among forms in morphological space (proportional to the mean squared distance among forms). Blastoid taxonomic diversity is based on published compilation of stratigraphic ranges of genera. The Zoological Record was used to determine the number of new species of trilobites described since the publication of the Treatise; temporal patterns in species richness are similar to those for generic richness based on the Treatise, suggesting a common underlying signal.

Morphological variety and taxonomic richness often increase together during the initial diversification of a clade. This pattern is consistent with diffusion through morphospace, although some form of adaptive radiation cannot be ruled out. Morphological diversity varies little throughout much of the history of Proetida, a pattern that may suggest major constraints on the magnitude and direction of evolution, and that agrees with the perception of Proetida as a morphologically conservative group. Two major patterns are seen during the decline of clades. In Blastoidea, Trilobita, Libristoma, and Asaphina, morphological diversity is maintained at substantial levels, and in fact continues to increase, even in the face of striking reductions in taxonomic richness. This pattern suggests continued diffusion through morphospace and taxonomic attrition that is effectively non-selective with respect to morphology. In Phacopida, Scutelluina, and to some extent in Proetida, morphological diversity decreases along with taxonomic diversity. This pattern suggests heterogeneities such as elevated extinction and/or reduced origination in certain regions of morphospace. As found previously for the echinoderm subphylum Blastozoa, all studied clades of trilobites except Proetida show maximal morphological diversity in the Mid–Late Ordovician and maximal taxonomic diversity sometime during the Ordovician, suggesting some degree of common control on diversification patterns in these groups.

Type
Articles
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Anstey, R. L., and Pachut, J. F. 1992. Cladogenesis and speciation in early bryozoans. Geological Society of America Abstracts with Programs 24:A139.Google Scholar
Bambach, R. K., and Sepkoski, J. J. Jr. 1992. Historical evolutionary information in the traditional Linnean hierarchy. P. 16in Lidgard, S. and Crane, P. R., eds. Fifth North American Paleontological Convention abstracts and program (Paleontological Society Special Publication No. 6). The University of Tennessee, Knoxville.Google Scholar
Breimer, A., and Macurda, D. B. Jr. 1972. The phylogeny of the fissiculate blastoids. Verhandelingen der Koninklijke Nederlandse Akademie van Wetenschappen, Afdeling Natuurkunde, Erste Reeks 26:1390.Google Scholar
Briggs, D. E. G., Fortey, R. A., and Wills, M. A. 1992. Morphological disparity in the Cambrian. Science 256:16701673.CrossRefGoogle ScholarPubMed
Broadhead, T. W. 1984. Macurdablastus, a middle Ordovician blastoid from the southern Appalachians. University of Kansas Paleontological Contributions, Paper 110:110.Google Scholar
Campbell, K. S. W., and Marshall, C. R. 1987. Rates of evolution among Palaeozoic echinoderms. Pp. 61100in Campbell, K. S. W. and Day, M. F., eds. Rates of evolution. Allen and Unwin, London.Google Scholar
Cherry, L. M., Case, S. M., Kunkel, J. G., Wyles, J. S., and Wilson, A. C. 1982. Body shape metrics and organismal evolution. Evolution 36:914933.CrossRefGoogle ScholarPubMed
Compston, W., Williams, I. S., Kirschvink, J. L., Zichao, Z., and Guogan, M. 1992. Zircon U-Pb ages for the Early Cambrian timescale. Journal of the Geological Society, London 149:171184.CrossRefGoogle Scholar
Cooper, J. A., Jenkins, R. J. F., Compston, W., and Williams, I. S. 1992. Ion-probe zircon dating of a mid-Early Cambrian tuff in South Australia. Journal of the Geological Society, London 149:185192.CrossRefGoogle Scholar
Cowie, J. W., and Harland, W. B. 1989. Chronometry. Pp. 186198in Cowie, J. W. and Brasier, M. D., eds. The Precambrian-Cambrian boundary. Clarendon, Oxford.Google Scholar
Efron, B. 1982. The jackknife, the bootstrap, and other resampling plans. Society for Industrial and Applied Mathematics, Philadelphia.CrossRefGoogle Scholar
Eldredge, N., and Braniša, L. 1980. Calmoniid trilobites of the Lower Devonian Scaphiocoelia Zone of Bolivia, with remarks on related species. Bulletin, American Museum of Natural History 165:181289.Google Scholar
Erwin, D. H. 1992. A preliminary classification of evolutionary radiations. Historical Biology 6:133147.CrossRefGoogle Scholar
Fisher, D. C. 1986. Progress in organismal design. Pp. 99117in Raup, D. M. and Jablonski, D., eds. Patterns and processes in the history of life. Springer, Berlin.CrossRefGoogle Scholar
Foote, M. 1988. Survivorship analysis of Cambrian and Ordovician trilobites. Paleobiology 14:258271.CrossRefGoogle Scholar
Foote, M. 1989. Perimeter-based Fourier analysis: a new morphometric method applied to the trilobite cranidium. Journal of Paleontology 63:880885.CrossRefGoogle Scholar
Foote, M. 1990. Nearest-neighbor analysis of trilobite morphospace. Systematic Zoology 39:371382.CrossRefGoogle Scholar
Foote, M. 1991a. Morphologic patterns of diversification: examples from trilobites. Palaeontology 34:461485.Google Scholar
Foote, M. 1991b. Morphological and taxonomic diversity in a clade's history: the blastoid record and stochastic simulations. Contributions from the Museum of Paleontology, University of Michigan 28:101140.Google Scholar
Foote, M. 1992a. Rarefaction analysis of morphological and taxonomic diversity. Paleobiology 18:116.CrossRefGoogle Scholar
Foote, M. 1992b. Paleozoic record of morphological diversity in blastozoan echinoderms. Proceedings, National Academy of Sciences, USA 89:73257329.CrossRefGoogle ScholarPubMed
Foote, M., and Gould, S. J. 1992. Cambrian and Recent morphological disparity. Science 258:1816.CrossRefGoogle ScholarPubMed
Fortey, R. A. 1990. Ontogeny, hypostome attachment and trilobite classification. Palaeontology 33:529576.Google Scholar
Fortey, R. A., and Chatterton, B. D. E. 1988. Classification of the trilobite suborder Asaphina. Palaeontology 31:165222.Google Scholar
Fortey, R. A., and Owens, R. M. 1975. Proetida—a new order of trilobites. Fossils and Strata 4:227239.CrossRefGoogle Scholar
Fortey, R. A. 1990a. Trilobites. Pp. 121142in McNamara, K. J., ed. Evolutionary trends. University of Arizona Press, Tucson.Google Scholar
Fortey, R. A. 1990b. Evolutionary radiations in the Trilobita. Pp. 139164in Taylor, P. D. and Larwood, G. P., eds. Major evolutionary radiations. Clarendon, Oxford.Google Scholar
Fortey, R. A., and Whittington, H. B. 1989. The Trilobita as a natural group. Historical Biology 2:125138.CrossRefGoogle Scholar
Gilinsky, N. L., Gould, S. J., and German, R. Z. 1989. Asymmetries of clade shape and the direction of evolutionary time. Science 243:16131614.CrossRefGoogle ScholarPubMed
Gould, S. J. 1989. Wonderful life: the Burgess Shale and the nature of history. Norton, New York.Google Scholar
Gould, S. J. 1991. The disparity of the Burgess Shale arthropod fauna and the limits of cladistic analysis: why we must strive to quantify morphospace. Paleobiology 17:411423.CrossRefGoogle Scholar
Gould, S. J., Gilinsky, N. L., and German, R. Z. 1987. Asymmetry of lineages and the direction of evolutionary time. Science 236:14371441.CrossRefGoogle ScholarPubMed
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 3:2340.CrossRefGoogle Scholar
Guensburg, T. E., and Sprinkle, J. 1992. Rise of echinoderms in the Paleozoic evolutionary fauna: significance of paleoenvironmental controls. Geology 20:407410.2.3.CO;2>CrossRefGoogle Scholar
Hallam, A. 1973. Atlas of palaeobiogeography. Elsevier, New York.Google 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, New York.Google Scholar
Harrington, H. J. et al. 1959. Systematic descriptions. Pp.O170–O539 in R. C. Moore, ed. Treatise on invertebrate paleontology, Part O, Arthropoda 1. The Geological Society of America and The University of Kansas Press, Boulder, Colo. and Lawrence, Kans.Google Scholar
Horowitz, A. S., Blakely, R. F., and Macurda, D. B. Jr. 1985. Taxonomic survivorship within the Blastoidea (Echinodermata). Journal of Paleontology 59:543550.Google Scholar
Jablonski, D. 1986. Mass and background extinctions: the alternation of macroevolutionary regimes. Science 231:129133.CrossRefGoogle ScholarPubMed
Kitchell, J. A., and MacLeod, N. L. 1988. Macroevolutionary interpretations of symmetry and synchroneity in the fossil record. Science 240:11901193.CrossRefGoogle ScholarPubMed
Kitchell, J. A. 1989. Asymmetries of clade shape and the direction of evolutionary time. Science 243:16141615.CrossRefGoogle ScholarPubMed
Kitchell, J. A., Clark, D. L., and Gombos, A. M. Jr. 1986. Biological selectivity and extinction: a link between background and mass extinction. Palaios 1:504511.CrossRefGoogle Scholar
Knoll, A. H., and Walter, M. R. 1992. Latest Proterozoic stratigraphy and Earth history. Nature 356:673678.CrossRefGoogle ScholarPubMed
Lane, P. D., and Thomas, A. T. 1983. A review of the trilobite suborder Scutelluina. Special Papers in Palaeontology 30:141160.Google Scholar
Lochman, C. 1956. The evolution of some upper Cambrian and Lower Ordovician trilobite families. Journal of Paleontology 30:445462.Google Scholar
Müller, A. H. 1955. Der Grossablauf der stammesgeschichtlichen Entwicklung. Fischer, Jena.Google Scholar
Müller, A. H. 1970. Eine phylogenetische Regel. Monatsberichte der deutschen Akademie der Wissenschaften zu Berlin 12:521531.Google Scholar
Müller, A. H. 1974. Regelhafte und systemgebundene Verlagerung der Formenmaxima sich stammesgeschictlich ablösender gleichrangiger Taxa, zweiter Nachtrag. Biologisches Zentralblatt 93:265288.Google Scholar
Pearson, E. S. 1926. Further note on the distribution of range in samples taken from a normal population. Biometrika 18:173194.CrossRefGoogle Scholar
Raup, D. M. 1966. Geometric analysis of shell coiling: general problems. Journal of Paleontology 40:11781190.Google Scholar
Raup, D. M. 1972. Taxonomic diversity during the Phanerozoic. Science 177:10651071.CrossRefGoogle ScholarPubMed
Raup, D. M. 1976. Species diversity in the Phanerozoic: a tabulation. Paleobiology 2:279288.CrossRefGoogle Scholar
Raup, D. M. 1978. Approaches to the extinction problem. Journal of Paleontology 52:517523.Google Scholar
Raup, D. M. 1992. Large-body impact and extinction in the Phanerozoic. Paleobiology 18:8088.CrossRefGoogle ScholarPubMed
Raup, D. M., and Gould, S. J. 1974. Stochastic simulation and evolution of morphology—towards a nomothetic paleontology. Systematic Zoology 23:305322.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. Journal of Geology 81:525542.CrossRefGoogle Scholar
Romer, A. S. 1949. Time series and trends in animal evolution. Pp. 103120in Jepsen, G. L., Mayr, E., and Simpson, G. G., eds. Genetics, paleontology, and evolution. Princeton University Press, Princeton, N.J.Google Scholar
Saunders, W. B., and Swan, A. R. H. 1984. Morphology and morphologic diversity of mid-Carboniferous (Namurian) ammonoids in time and space. Paleobiology 10:195228.CrossRefGoogle 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
Simpson, G. G. 1953. The major features of evolution. Columbia University Press, New York.CrossRefGoogle Scholar
Sloan, R. E. 1991. A chronology of North American Ordovician trilobite genera. Geological Society of Canada, Paper 90–9:165177.CrossRefGoogle Scholar
Sloss, L. L. 1950. Rates of evolution. Journal of Paleontology 24:131139.Google Scholar
Sokal, R. R., and Rohlf, F. J. 1981. Biometry, 2d ed. W. H. Freeman, San Francisco.Google Scholar
Sprinkle, J. 1980. Early diversification. Pp. 8691in Broadhead, T. W. and Waters, J. A., eds. Echinoderms: notes for a short course. University of Tennessee, Knoxville.Google Scholar
Stanley, S. M. 1968. Post-Paleozoic adaptive radiation of infaunal bivalve molluscs—a consequence of mantle fusion and siphon formation. Journal of Paleontology 42:214229.Google Scholar
Stanley, S. M. 1979. Macroevolution: pattern and process. W. H. Freeman, San Francisco.Google Scholar
Stubblefield, C. J. 1960. Evolution in trilobites. Quarterly Journal of the Geological Society of London 115:145162.CrossRefGoogle Scholar
Valentine, J. W. 1969. Patterns of taxonomic and ecological structure of the shelf benthos during Phanerozoic time. Palaeontology 12:684709.Google Scholar
Valentine, J. W. 1980. Determinants of diversity in higher taxonomic categories. Paleobiology 6:444450.CrossRefGoogle Scholar
Valentine, J. W. 1986. Fossil record of the origin of Baupläne and its implications. Pp. 209222in Raup, D. M. and Jablonski, D., eds. Patterns and processes in the history of life. Springer, Berlin.CrossRefGoogle Scholar
Valentine, J. W., and Erwin, D. H. 1987. Interpreting great developmental experiments: the fossil record. Pp. 71107in Raff, R. A. and Raff, E. C., eds. Development as an evolutionary process. Liss, New York.Google Scholar
Valentine, J. W., and Walker, T. D. 1987. Extinctions in a model taxonomic hierarchy. Paleobiology 13:193207.CrossRefGoogle Scholar
Van Valen, L. 1971. Adaptive zones and the orders of mammals. Evolution 25:420428.CrossRefGoogle ScholarPubMed
Van Valen, L. 1974. Multivariate structural statistics in natural history. Journal of Theoretical Biology 45:235247.CrossRefGoogle ScholarPubMed
Waters, J. A. 1988. The evolutionary palaeoecology of the Blastoidea. Pp. 215233in Paul, C. R. C. and Smith, A. B., eds. Echinoderm phylogeny and evolutionary biology. Clarendon, Oxford.Google Scholar
Whittington, H. B. 1966. Phylogeny and distribution of Ordovician trilobites. Journal of Paleontology 40:696737.Google Scholar
Whittington, H. B. 1980. The significance of the fauna of the Burgess Shale, Middle Cambrian, British Columbia. Proceedings of the Geologists' Association 91:127148.CrossRefGoogle Scholar
Whittington, H. B., and Hughes, C. P. 1972. Ordovician geography and faunal provinces deduced from trilobite distribution. Philosophical Transactions of the Royal Society of London B 263:235278.Google Scholar
Williams, A. 1957. Evolutionary rates of brachiopods. Geological Magazine 94:201211.CrossRefGoogle Scholar