Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-26T19:54:00.011Z Has data issue: false hasContentIssue false
  • English
  • Français

Disparity as an evolutionary index: a comparison of Cambrian and Recent arthropods

Published online by Cambridge University Press:  08 February 2016

Matthew A. Wills ,
Derek E. G. Briggs  and
Richard A. Fortey
Matthew A. Wills
Affiliation:
Department of Geology, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, United Kingdom
Derek E. G. Briggs
Affiliation:
Department of Geology, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, United Kingdom
Richard A. Fortey
Affiliation:
Department of Palaeontology, Natural History Museum, Cromwell Road, South Kensington, London SW7 5BD, United Kingdom
Get access Rights & Permissions [Opens in a new window]

Abstract

Disparity is a measure of the range or significance of morphology in a given sample of organisms, as opposed to diversity, which is expressed in terms of the number (and sometimes ranking) of taxa. At present there is no agreed definition of disparity, much less any consensus on how to measure it. Two possible categories of metric are considered here, one independent of any hypothesis of relationship (phenetics), the other constrained within an evolutionary framework (cladistics).

The Early Cambrian radiation was clearly a period of significant morphologic and taxonomic diversification. However, we question the interpretation of its first generation products as numerous body plans at the highest level. Four phenetic and two cladistic measures have been used to compare disparity among Cambrian arthropods with that in the living fauna. Phenetic methods assessing character-state variability and the amount of morphological attribute space occupied yield similar results for Cambrian and Recent arthropods. Assessments of disparity within a taxonomic framework rely on the identification of particular characters that delineate higher level body plans. This requires a phylogenetic interpretation, a cladistic investigation of hierarchical structure in the data. Both sets of arthropods fall within the same major clades, and within this cladistic framework the amount of character-state evolution in the two groups is comparable. None of these methods identifies markedly greater disparity among the Cambrian compared with the Recent taxa.

Although measures of disparity are applied here to a consideration of the Cambrian radiation, the metrics clearly have a much wider potential for estimating macroevolutionary trends independently from existing taxonomic frameworks. Geometric morphometry is ideal for measuring morphological variety at lower taxonomic levels, but it requires the recognition of homologous landmarks in all the forms under comparison, or the identification of entire homologous structures. Conventional phenetics has much wider application as it can operate on data coded as discrete homologous character states (this facility is also a requirement of cladistics), which are a more appropriate basis for comparing disparity in markedly dissimilar forms.

Type
Articles
Information
Paleobiology , Volume 20 , Issue 2 , Spring 1994 , pp. 93 - 130
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

Anderson, D. T. 1973. Embryology and phylogeny of the annelids and arthropods. Pergamon, Oxford.Google Scholar
Archie, J. W. 1989a. A randomization test for phylogenetic information in systematic data. Systematic Zoology 38:239–252.CrossRefGoogle Scholar
Archie, J. W. 1989b. Homoplasy excess ratios: new indices for measuring levels of homoplasy in systematics and a critique of the consistency index. Systematic Zoology 38:253–269.CrossRefGoogle Scholar
Archie, J. W. 1989c. Phylogenies of plant families: a demonstration of phylogenetic randomness in DNA sequence data derived from proteins. Systematic Zoology 38:239–252.CrossRefGoogle Scholar
Ballard, J. W. O., Olsen, G. J., Faith, D. P., Odgers, W. A., Rowell, D. M., and Atkinson, P. W. 1992. Evidence from 12S ribosomal RNA that onychophorans are modified arthropods. Science 258:1345–1348.CrossRefGoogle ScholarPubMed
Bard, J. 1990. The fifth day of creation. Bioessays 12:303–306.CrossRefGoogle Scholar
Bergström, J. 1976. Early arthropod morphology and relationships. Twenty-fifth International Geological Congress Abstracts, p. 289.Google Scholar
Bergström, J. 1979. Morphology of fossil arthropods as a guide to phylogenetic relationships. Arthropod phylogeny. Pp. 3–56in Gupta, 1979.Google Scholar
Bergström, J. 1981. Morphology and systematics of early arthropods. Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg 23:7–42.Google Scholar
Bergström, J. 1992. The oldest arthropods and the origin of the Crustacea. Acta Zoologica 73:287–291.CrossRefGoogle Scholar
Bookstein, F. L., Chernoff, B., Elder, R. L., Humphries, J. M., Smith, G. R., and Strauss, R. E. 1985. Morphometrics in evolutionary biology. Academy of Natural Sciences, Philadelphia, Special Publication 15.Google Scholar
Boudreaux, H. B. 1979a. Significance of intersegmental tendon systems in arthropod phylogeny, and a monophyletic classification of the Arthropoda. Pp. 551–586in Gupta, 1979.Google Scholar
Boudreaux, H. B. 1979b. Arthropod phylogeny, with special reference to insects. Wiley, New York.Google Scholar
Briggs, D. E. G. 1981. The arthropod Odaraia alata Walcott, Middle Cambrian, Burgess Shale, British Columbia. Transactions of the Royal Society, London B 291:541–585.Google Scholar
Briggs, D. E. G. 1983. Affinities and early evolution of the Crustacea: the evidence of the Cambrian fossils. Pp. 1–22in Schram, F. R., ed. Crustacean phylogeny. Balkema, Rotterdam.Google Scholar
Briggs, D. E. G. 1990. Early arthropods: dampening the Cambrian explosion. Pp. 24–43in Culver, S. J., ed. Arthropod paleobiology. Short courses in paleontology, no. 3. Paleontological Society, Knoxville, Tenn.Google Scholar
Briggs, D. E. G., and Collins, D. 1988. A Middle Cambrian chelicerate from Mount Stephen, British Columbia. Paleontology 31:71–73.Google Scholar
Briggs, D. E. G., and Fortey, R. A. 1989. The early radiation and relationships of the major arthropod groups. Science 246:241–243.CrossRefGoogle ScholarPubMed
Briggs, D. E. G., and Whittington, H. B. 1981. Relationships of arthropods from the Burgess Shale and other Cambrian sequences. Pp. 38–41in Taylor, M. E., ed. Short papers for the Second International Symposium on the Cambrian System. U.S. Geological Survey, Open File Report 81-743.Google Scholar
Briggs, D. E. G., and Whittington, H. B. 1985. The mode of life of the Burgess Shale arthropods. Transactions of the Royal Society of Edinburgh; Earth Sciences 76:149–160.CrossRefGoogle Scholar
Briggs, D. E. G., Fortey, R. A., and Wills, M. A. 1992a. Morphological disparity in the Cambrian. Science 256:1670–1673.CrossRefGoogle ScholarPubMed
Briggs, D. E. G., Fortey, R. A., and Wills, M. A. 1992b. Cambrian and Recent morphological disparity. (Response to Foote and Gould, and Lee). Science 258:1817–1818.CrossRefGoogle Scholar
Briggs, D. E. G., Fortey, R. A., and Wills, M. A. 1993. How big was the Cambrian explosion? A taxonomic and morphologic comparison of Cambrian and Recent arthropods. Pp. 33–44in Lees, D. R. and Edwards, D., eds. Evolutionary patterns and processes. Linnean Society Symposium Series. Linnean Society of London.Google Scholar
Brusca, R. C., and Brusca, G. J. 1990. Invertebrates. Sinauer, Mass.Google Scholar
Bruton, D. L., and Whittington, H. B. 1983. Emeraldella and Leanchoilia, two arthropods from the Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society, London B 300:553–585.Google Scholar
Butterfield, N. J. 1990. A reassessment of the enigmatic Burgess Shale fossil Wiwaxia corrugata (Matthew) and its relationship to the polychaete Canadia spinosa Walcott. Paleobiology 16:287–303.CrossRefGoogle Scholar
Calman, W. T. 1909. Crustacea. Pp. 1–346in Lankester, R., ed. Treatise on zoology VII (Appendiculata) (Fascicule 3). Adam & Black, 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 35:914–933.CrossRefGoogle Scholar
Cisne, J. L. 1974. Trilobites and the origins of arthropods. Science 186:13–18.CrossRefGoogle ScholarPubMed
Conway Morris, S. 1985. The Middle Cambrian metazoan Wiwaxia corrugata (Matthew) from the Burgess Shale and Ogygopsis Shale, British Columbia, Canada. Philosophical Transactions of the Royal Society of London B 307:507–586.Google Scholar
Conway Morris, S. 1986. The community structure of the Middle Cambrian phyllopod bed (Burgess Shale). Palaeontology 29:423–467.Google Scholar
Conway Morris, S. 1992. Burgess Shale-type faunas in the context of the “Cambrian explosion”: a review. Journal of the Geological Society of London 149:631–636.CrossRefGoogle Scholar
Donoghue, M. J., Doyle, J. A., Gauthier, J., Kluge, A. G., and Rowe, T. 1989. The importance of fossils in phylogeny reconstruction. Annual Review of Ecology and Systematics 20:431–460.CrossRefGoogle Scholar
Dunn, G., and Everitt, B. S. 1982. An introduction to mathematical taxonomy. Cambridge University Press, Cambridge.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 Cracraft, J. 1980. Phylogenetic patterns and the evolutionary process. Columbia University Press, New York.Google Scholar
Erwin, D. H. 1990. Carboniferous–Triassic gastropod diversity patterns and the Permo-Triassic mass extinction. Paleobiology 16:187–203.CrossRefGoogle Scholar
Erwin, D. H. 1992. A preliminary classification of evolutionary radiations. Historical Biology 6:133–147.CrossRefGoogle Scholar
Faith, D. P., and Cranston, P. S. 1991. Could a cladogram this short have arisen by chance alone? On permutation tests for cladistic structure. Cladistics 7:1–28.CrossRefGoogle Scholar
Field, K. G., Olsen, G. J., Lane, D. J., Giovannoni, S. J., Ghiselin, M. T., Raff, E. C., Pace, N. R., and Raff, R. A. 1988. Molecular phylogeny of the animal kingdom. Science 239:748–753.CrossRefGoogle ScholarPubMed
Foote, M. 1989. Perimeter-based Fourier analysis: a new morphometric method applied to the trilobite cranidium. Journal of Paleontology 63:880–885.CrossRefGoogle Scholar
Foote, M. 1990. Nearest-neighbor analysis of trilobite morphospace. Systematic Zoology 39:371–382.CrossRefGoogle Scholar
Foote, M. 1991a. Morphologic patterns of diversification: examples from trilobites. Palaeontology 34:461–485.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, the University of Michigan 28:101–140.Google Scholar
Foote, M. 1991c. Analysis of morphological data. Pp. 59–86in Gilinsky, N. L., and Signor, P. W., eds. Analytical paleobiology. Short courses in paleontology, no. 4. Paleontological Society, Knoxville, Tenn.Google Scholar
Foote, M. 1992a. Rarefaction analysis of morphological and taxonomic diversity. Paleobiology 18:17–29.CrossRefGoogle Scholar
Foote, M. 1992b. Paleozoic record of morphological diversity in blastozoan echinoderms. Proceedings of the National Academy of Science, USA 89:7325–7329.CrossRefGoogle ScholarPubMed
Foote, M. 1993. Discordance and concordance between morphological and taxonomic diversity. Paleobiology 19:185–204.CrossRefGoogle Scholar
Foote, M., and Gould, S. J. 1992. Cambrian and Recent morphological disparity. Science 258:1816.CrossRefGoogle ScholarPubMed
Fortey, R. A., and Owens, R. M. 1990. Trilobites. Pp. 121–142in McNamara, K. J., ed. Evolutionary trends. University of Arizona Press, Tucson.Google Scholar
Fryer, G. 1992. The origin of the Crustacea. Acta Zoologica 73:273–286.CrossRefGoogle Scholar
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 17:411–423.CrossRefGoogle Scholar
Gower, J. C. 1966. Some distance properties of latent root and vector methods used in multivariate analysis. Biometrika 53:325–338.CrossRefGoogle Scholar
Gower, J. C., and Ross, G. J. S. 1969. Minimum spanning trees and single-linkage cluster analysis. Applied Statistics 18:54–64.CrossRefGoogle Scholar
Gupta, A. P. 1979. Arthropod phylogeny. Van Nostrand, New York.Google Scholar
Hessler, R. R., and Newman, W. A. 1975. A trilobitomorph origin for the Crustacea. Fossils and Strata 4:437–459.CrossRefGoogle Scholar
Iwanoff, P. P. 1928. Die entwicklung der Larvalsegmente bei den anneliden. Zeitschrift für Morphologie und Ökologie der Tiere 10:62–161.CrossRefGoogle Scholar
Jeffers, J. N. R. 1967. Two case studies in the application of principal component analysis. Applied Statistics 16:225–236.CrossRefGoogle Scholar
Kovach, W. L. 1990. MVSP users' manual. Cambrian Printers, Aberystwyth.Google Scholar
Kruskal, J. B. 1964a. Multidimensional scaling by optimizing goodness of fit to a nonmetric hypothesis. Psychometrica 29:1–27.CrossRefGoogle Scholar
Kruskal, J. B. 1964b. Nonmetric multidimensional scaling: a numerical method. Psychometrica 29:1–27.CrossRefGoogle Scholar
Lee, M. S. Y. 1992. Cambrian and Recent morphological disparity. Science 258:1816–1817.CrossRefGoogle ScholarPubMed
McMenamin, M. A. S., and McMenamin, D. L. S. 1990. The emergence of animals, the Cambrian breakthrough. Columbia University Press, New York.CrossRefGoogle Scholar
Patterson, C., and Rosen, D. E. 1977. Review of ichthyodectiform and other Mesozoic teleost fishes and the theory and practice of classifying fossils. Bulletin of the American Museum of Natural History 158:81–172.Google Scholar
Pielou, E. C. 1975. Ecological diversity. Wiley, New York.Google Scholar
Pimentel, R. A., and Riggins, R. 1987. The nature of cladistic data. Cladistics 3:201–209.CrossRefGoogle Scholar
Ramsköld, L., and Edgecombe, G. D. 1991. Trilobite monophyly revisited. Historical Biology 4:267–283.CrossRefGoogle Scholar
Raup, D. M., and Gould, S. J. 1974. Stochastic simulation and evolution of morphology—towards a nonmothetic paleontology. Systematic Zoology 23:305–322.CrossRefGoogle Scholar
Ridley, M. 1990. Dreadful beasts. The London Review of Books, June 28:11–12.Google Scholar
Riedl, R. 1978. Order in living organisms. Wiley, New York.Google Scholar
Rohlf, F. J. 1973. Algorithm 76. Hierarchical clustering using the minimum spanning tree. Computer Journal 16:93–95.Google Scholar
Rohlf, F. J., and Sokal, R. R. 1965. Coefficients of correlation and distance in numerical taxonomy. University of Kansas Scientific Bulletin 45:3–27.Google Scholar
Runnegar, B. 1987. Rates and modes of evolution in the Mollusca. Pp. 39–60in Campbell, K. S. W. and Day, M. F., eds. Rates of evolution. Allen and Unwin, London.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 10:195–228.CrossRefGoogle Scholar
Schank, J. C., and Wimsatt, W. C. 1986. Generative entrenchment and evolution. Philosophy of Science Association 2:33–60.Google Scholar
Schram, F. R. 1978. Arthropods: a convergent phenomenon. Fieldiana: Geology 39:61–108.Google Scholar
Sepkoski, J. J. Jr., and Kendrick, D. C. 1993. Numerical experiments with model monophyletic and paraphyletic taxa. Paleobiology 19:168–184.CrossRefGoogle ScholarPubMed
Sharov, A. G. 1966. Basic arthropodan stock. Pergamon, New York.Google Scholar
Shepard, R. N. 1962. The analysis of proximities: multidimensional scaling with an unknown distance function, I and II. Psychometrika 27:125–140, 219-246.CrossRefGoogle Scholar
Shepard, R. N. 1966. Metric structures in oridinal data. Journal of Mathematical Psychology 3:287–315.CrossRefGoogle Scholar
Shergold, J. H. 1991. Protaspid and early meraspid growth stages of the eodiscoid trilobite Pagetia ocellata Jell, and their implications for classification. Alcheringa 15:65–86.CrossRefGoogle Scholar
Simonetta, A., and Delle Cave, L. 1975. The Cambrian non trilobite arthropods from the Burgess Shale of British Columbia. A study of their comparative morphology, taxonomy and evolutionary significance. Palaeontographica Italica 69:1–37.Google Scholar
Smith, A. B. 1994. Systematics and the fossil record: documenting evolutionary patterns. Blackwell Scientific, Boston.CrossRefGoogle Scholar
Sneath, P. H. A. 1962. The construction of taxonomic groups. Pp. 289–332in Ainsworth, G. C. and Sneath, P. H. A., eds. Microbial classification. Twelfth Symposium of the Society for General Microbiology. Cambridge University Press.Google Scholar
Sneath, P. H. A., and Sokal, R. R. 1973. Numerical taxonomy. W. H. Freeman, San Francisco.Google Scholar
Snodgrass, R. E. 1938. The evolution of the Annelida, Onychophora and Arthropoda. Smithsonian Miscellaneous Collections 97:1–59.Google Scholar
Snodgrass, R. E. 1950. Comparative studies of the jaws of mandibulate arthropods. Smithsonian Miscellaneous Collections 116:1–85.Google Scholar
Snodgrass, R. E. 1956. Crustacean metamorphosis. Smithsonian Miscellaneous Collections 131:1–78.Google Scholar
Snodgrass, R. E. 1958. Evolution of arthropod mechanisms. Smithsonian Miscellaneous Collections 138:1–77.Google Scholar
Sokal, R. R. 1961. Distance as a measure of taxonomic similarity. Systematic Zoology 10:70–79.CrossRefGoogle Scholar
Sokal, R. R., and Michener, C. D. 1958. A statistical method for evaluating systematic relationships. University of Kansas Scientific Bulletin 38:1409–1438.Google Scholar
Sokal, R. R., and Sneath, P. H. A. 1963. Princples of numerical taxonomy. W. H. Freeman, San Francisco.Google Scholar
Størmer, L. 1944. On the relationships and phylogeny of fossil and Recent Arachnomorpha. Skrifter utgitt av det Norske Vidensk Academi i Oslo 5:1–158.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 Zoological Society of London 115:145–162.Google Scholar
Swofford, D. L. 1990. PAUP: phylogenetic analysis using parsimony, version 3.0. Computer program distributed by the Illinois Natural History Survey, Champaign, Illinois.Google Scholar
Temple, J. T. 1980. A numerical taxonomic study of the Trinucleidae (Trilobita) from the British Isles. Transactions of the Royal Society of Edinburgh 71:213–233.CrossRefGoogle Scholar
Temple, J. T. 1982. Ordination of palaeontological data. Miscellaneous Papers of the Geological Society of London 14:224–236.Google Scholar
Temple, J. T., and Tripp, R. P. 1979. An investigation of the Encrinurinae (Trilobita) by numerical taxonomic methods. Transactions of the Royal Society of Edinburgh 70:223–250.CrossRefGoogle Scholar
Temple, J. T., and Wu, H.-J. 1990. Numerical taxonomy of Encrinurinae (Trilobita): additional species from China and elsewhere. Transactions of the Royal Society of Edinburgh 81:209–219.CrossRefGoogle Scholar
Turbeville, J. M., Pfeifer, D. M., Field, K. G., and Raff, R. A. 1991. The phylogenetic status of arthropods, as inferred from 18S RNA sequences. Journal of Molecular Evolution 8:669–686.Google Scholar
Valentine, J. W. 1969. Patterns of taxonomic and ecological structure of the shelf benthos during Phanerozoic time. Palaeontology 12:684–709.Google Scholar
Valentine, J. W. 1977. General patterns in Metazoan evolution. Pp. 27–57in Hallam, A., ed. Patterns of evolution as illustrated by the fossil record. Elsevier Scientific, Oxford.CrossRefGoogle Scholar
Valentine, J. W. 1989. Bilaterians of the Precambrian-Cambrian transition and the annelid-arthropod relationship. Proceedings of the National Academy of Sciences, USA. 86:2272–2275.CrossRefGoogle ScholarPubMed
Van Valen, L. 1974. Multivariate structural statistics in natural history. Journal of Theoretical Biology 45:235–247.CrossRefGoogle ScholarPubMed
Walcott, C. D. 1908. Mount Stephen rocks and fossils. Canadian Alpine Journal 1:232–248.Google Scholar
Walcott, C. D. 1911. Middle Cambrian Merostomata. Cambrian geology and palaeontology, II. Smithsonian Miscellaneous Collections 57:17–40.Google Scholar
Walcott, C. D. 1912. Middle Cambrian Branchiopoda, Malacostraca, Trilobita and Merostomata. Cambrian geology and palaeontology, II. Smithsonian Miscellaneous Collections 57:109–144.Google Scholar
Weygoldt, P. 1979. Significance of later embryonic stages and head development in arthropod phylogeny. Pp. 107–135in Gupta, 1979.Google Scholar
Whittington, H. B. 1985. The Burgess Shale. Yale University Press, New Haven.Google Scholar
Wiley, E. O. 1981. Phylogenetics: the theory and practice of phylogenetic systematics. Wiley, New York.Google Scholar
Wimsatt, W. C., and Schank, J. C. 1988. Two constraints on the evolution of complex adaptations and the means for their avoidance. Pp. 231–237in Nitecki, M. H., ed. Evolutionary progress. University of Chicago Press.Google Scholar