Hostname: page-component-7479d7b7d-68ccn Total loading time: 0 Render date: 2024-07-10T11:26:17.096Z Has data issue: false hasContentIssue false

Detecting changes in morphospace occupation patterns in the fossil record: characterization and analysis of measures of disparity

Published online by Cambridge University Press:  20 May 2016

Charles N. Ciampaglio
Affiliation:
Department of Biology, Duke University, Durham, North Carolina 27708. CNC2@duke.edu
Matthieu Kemp
Affiliation:
Department of Biology, Duke University, Durham, North Carolina 27708. CNC2@duke.edu
Daniel W. McShea
Affiliation:
Department of Biology, Duke University, Durham, North Carolina 27708. CNC2@duke.edu

Abstract

Recently, there has been much interest in detecting and measuring patterns of change in disparity. Although most studies have used one or two measures of disparity to quantify and characterize the occupation of morphospace, multiple measures may be necessary to fully detect changes in patterns of morphospace occupation. Also, the ability to detect morphological trends and occupation patterns within morphospace depends on using the appropriate measure(s) of disparity. In this study, seven measures were used to determine and characterize sensitivity to sample size of the data, number of morphological characters, percentage of missing data, and changes in morphospace occupation pattern. These consist of five distance measures—sum of univariate variances, total range, mean distance, principal coordinate analysis volume, average pairwise dissimilarity—and two non-distance measures—participation ratio and number of unique pairwise character combinations. Evaluation of each measure with respect to sensitivity to sample size, number of morphological characters, and percentage of missing data was accomplished by using both simulated and Ordovician crinoid data. For simulated data, each measure of disparity was evaluated for its response to changes of morphospace occupation pattern, and with respect to simulated random and nonrandom extinction events. Changes in disparity were also measured within the Crinoidea across the Permian extinction event.

Although all measures vary in sensitivity with respect to species sample size, number of morphological characters, and percentage of missing data, the non-distance measures overall produce the lowest estimates of variance (in bootstrap analyses). The non-distance measures appear to be relatively insensitive to changes in morphospace occupation pattern. All measures, except average pairwise dissimilarity, detect changes in occupation pattern in simulated nonrandom extinction events, but all measures, except number of unique pairwise character combinations and principal coordinate analysis volume, are relatively insensitive to changes in pattern in simulated random extinction events. The distance measures report similar changes in disparity over the Permian extinction event, whereas the non-distance measures differ. This study suggests that each measure of disparity is designed for different purposes, and that by using a combination of techniques a clearer picture of disparity should emerge.

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

Eble, G. J. 2000. Contrasting evolutionary flexibility in sister groups: disparity and diversity in Mesozoic atelostomate echinoids. Paleobiology 26:5679.Google Scholar
Economou, E. N. 1983. Green's functions in quantum physics. Springer, Heidelberg.Google Scholar
Efron, B. 1982. The jacknife, the bootstrap, and other resampling plans. Society for Industrial and Applied Mathematics, Philadelphia.Google Scholar
Erwin, D. H. 1994. Early introduction of major morphological innovations. Acta Palaeontologica Polonica 38:281294.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.Google Scholar
Foote, M. 1993. Discordance and concordance between morphological and taxonomic diversity. Paleobiology 19:185204.Google Scholar
Foote, M. 1994. Morphological disparity in Ordovician-Devonian crinoids and the early saturation of morphological space. Paleobiology 20:320344.Google Scholar
Foote, M. 1995. Analysis of morphological data. In Gilinsky, N. L.Signor, P. W., eds. Analytical paleobiology. Short Courses in Paleontology 14:5986. Paleontological Society, Knoxville, Tenn.Google Scholar
Foote, M. 1996. Ecological controls on the evolutionary recovery of post-Paleozoic crinoids. Science 274:14921495.Google Scholar
Foote, M. 1997. The evolution of morphological disparity. Annual Review of Ecology and Systematics 28:129152.CrossRefGoogle Scholar
Foote, M. 1999. Morphological diversity in the evolutionary radiation of Paleozoic and Post-Paleozoic crinoids. Paleobiology Memoirs No. 1. Paleobiology 25(Suppl. to No. 2).Google Scholar
Gould, S. J. 1989. Wonderful life. 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.Google Scholar
Gould, S. J.Raup, D. M.Sepkoski, J. J. Jr.Schopf, T. J. M.Simberloff, D. S. 1977. The shape of evolution: a comparison of real and random clades. Paleobiology 3:2340.Google Scholar
Lupia, R. 1999. Discordant morphological disparity and taxonomic diversity during the Cretaceous angiosperm radiation: North American pollen record. Paleobiology 25:128.Google Scholar
O'Keefe, F. R.Sander, P. M. 1999. Paleontological paradigms and inferences of phylogenetic pattern: a case study. Paleobiology 25:518533.Google Scholar
Raup, D. M. 1977. Stochastic models in evolutionary paleontology. Pp. 5978in Hallam, A., ed. Patterns of evolution as illustrated by the fossil record: developments in paleontology and stratigraphy. Elsevier, Amsterdam.Google Scholar
Raup, D. M.Gould, S. J. 1974. Stochastic simulation and evolution of morphology—towards a nomothetic paleontology. Systematic Zoology 23:305322.Google Scholar
Smith, A. B. 1994. Systematics and the fossil record: documenting evolutionary patterns. Blackwell Scientific, Oxford.Google Scholar
Smith, L. H.Bunje, P. M. 1999. Morphologic diversity of inarticulate brachiopods through the Phanerozoic. Paleobiology 25:396408.Google Scholar
Smith, L. H.Lieberman, B. S. 1999. Disparity and constraint in olenelloid trilobites and the Cambrian radiation. Paleobiology 25:459470.Google Scholar
Sneath, P. H. A.Sokal, R. R. 1973. Numerical taxonomy. W. H. Freeman, San Francisco.Google Scholar
Thomas, R. D. K.Reif, W. E. 1993. The skeleton space: a finite set of organic designs. Evolution 47:341360.Google Scholar
Thomas, R. D. K.Shearman, R. M.Stewart, G. W. 2000. Evolutionary exploitation of design options by the first animals with hard skeletons. Science 288:2391242.Google Scholar
Valentine, J. W. 1986. Fossil record of the origin of Bauplane and its implications. Pp. 209232in Raup, D. M.Jablonski, D., eds. Patterns and processes in the history of life. Springer, Berlin.CrossRefGoogle Scholar
Valentine, J. W.Erwin, D. H. 1985. Interpreting great developmental experiments: the fossil record. Pp. 71108in Raff, R. A.Raff, E. C., eds. Development as an evolutionary process. Alan R. Liss, New York.Google Scholar
Van Valen, L. 1974. Multivariate structural statistics in natural history. Journal of Theoretical Biology 45:235247.Google Scholar
Wagner, P. J. 1995. Systematics and the fossil record. Palaios 10:383388.Google Scholar
Wagner, P. J. 1997. Patterns of morphologic diversification among the Rostroconchia. Paleobiology 23:115150.Google Scholar
Wills, M. A.Briggs, D. E. G.Fortey, R. A. 1994. Disparity as an evolutionary index: a comparison of Cambrian and Recent arthropods. Paleobiology 20:93130.Google Scholar