Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-16T14:48:17.775Z Has data issue: false hasContentIssue false

Shape disassociation and inferred heterochrony in a clade of pachypleurosaurs (Reptilia, Sauropterygia)

Published online by Cambridge University Press:  08 February 2016

F. Robin O'Keefe
Affiliation:
Committee on Evolutionary Biology, University of Chicago, Chicago, Illinois 60637. E-mail: frokeefe@midway.uchicago.edu
Olivier Rieppel
Affiliation:
Department of Geology, Field Museum of Natural History, Chicago, Illinois 60605
P. Martin Sander
Affiliation:
Institut für Paläontologie der Universität Bonn, Nussallee 8, D-53115 Bonn, Germany

Abstract

In this paper we analyze the ontogenies of four species of pachypleurosaur (Reptilia: Sauropterygia) occurring in Triassic-age deposits in the Monte San Giorgio region, Switzerland. Preservation of multiple complete specimens representing a growth series from each taxon allows the comparison of ontogenetic trajectories through a space composed of nine variables important in the evolution of the clade. Trajectories are characterized using the multivariate generalization of the allometry equation and then compared through calculations of the angles between allometry vectors. Individual coefficients of vectors are compared after calculation of bootstrapped confidence intervals. Pachypleurosaur ontogeny is found to be allometric and generally conserved, although significant differences between taxa exist. Shape-disassociated allometric changes characterize the transition between Serpianosaurus and Neusticosaurus, while allometric changes within Neusticosaurus are less significant. N. edwardsii is inferred to have arisen through hypermorphosis. Interpretation of whole-body heterochrony in multivariate analysis is discussed.

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

Airoldi, J. P., and Flury, B. K. 1988. An application of common principal component analysis to cranial morphometry of Microtus californicus and M. ochrogaster (Mammalia, Rodentia). Journal of Zoology 216:2136.CrossRefGoogle Scholar
Alberch, P. S., Gould, S. J., Oster, G. F., and Wake, D. B. 1979. Size and shape in ontogeny and phylogeny. Paleobiology 5:296317.CrossRefGoogle Scholar
Anderson, T. W. 1963. Asymptotic theory for principal component analysis. Annals of Mathematical Statistics 34:122148.CrossRefGoogle Scholar
Arnold, S. J., and Bennett, A. F. 1988. Behavioral variation in natural populations. V. Morphological correlates of locomotion in the garter snake (Thomnophis radix). Biological Journal of the Linnean Society 34:175190.CrossRefGoogle Scholar
Bookstein, F., Chernoff, B., Elder, R., Humphries, J., Smith, G., and Strauss, R. 1985. Morphometrics in evolutionary biology. Academy of Natural Sciences of Philadelphia Special Publication 15.Google Scholar
Bürgin, T., Eichenberger, U., Furrer, H., and Tschanz, K. 1991. Die Prosanto-Formation—eine fischreiche Fossil-Lagerstätte in der Mitteltrias der Silvretta-Decke (Kanton Gaubünden, Schweiz). Eclogae Geologicae Helvetiae 84:921990.Google Scholar
Carroll, R. L., and Gaskill, P. 1985. The nothosaur Pachypleurosaurus and the origin of plesiosaurs. Philosophical Transactions of the Royal Society of London B 309:343393.Google Scholar
Efron, B., and Tibshirani, R. 1986. Bootstrap methods for standard errors, confidence intervals, and other measures of statistical accuracy. Statistical Science 1:5477.Google Scholar
Felsenstein, J. 1988. Phylogenies and quantitative characters. Annual Review of Ecology and Systematics 19:445471.CrossRefGoogle Scholar
Fink, W. L. 1982. The conceptual relationship between ontogeny and phylogeny. Paleobiology 8:254264.CrossRefGoogle Scholar
Fink, W. L. 1988. Phylogenetic analysis and the detection of ontogenetic patterns. Pp. 7191in McKinney, 1988.Google Scholar
Furrer, H. 1995. The Kalkschieferzone (Upper Meride Limestone; Ladinian) near Meride (Canton Ticino, Southern Switzerland) and the evolution of a Middle Triassic intraplatform basin. Eclogae Geologicae Helvetiae 88:827852.Google Scholar
Gaetani, M., Gnaccolini, M., Poliasni, G., Grignani, D., Gorza, M., and Matrellini, L. 1992. An anoxic intraplatform basin in the Middle Triassic of Lombardy (southern Alps, Italy): anatomy of a hydrocarbon source. Revista de Italiano Paleontology y Stratigraphy 97:329354.Google Scholar
Godfrey, L. R., and Sutherland, M. R. 1995a. Flawed inference: why size-based tests of heterochronic processes do not work. Journal of Theoretical Biology 172:4361.CrossRefGoogle Scholar
Godfrey, L. R., and Sutherland, M. R. 1995b. What's growth got to do with it? Process and product in the evolution of ontogeny. Journal of Human Evolution 29:405431.CrossRefGoogle Scholar
Godfrey, L. R., and Sutherland, M. R. 1996. Paradox of peramorphic paedomorphosis: heterochrony and human evolution. American Journal of Physical Anthroplogy 99:1742.CrossRefGoogle ScholarPubMed
Gould, S. J. 1977. Ontogeny and phylogeny. Harvard University Press, Cambridge.Google Scholar
Hafner, J. C., and Hafner, M. S. 1988. Heterochrony in rodents. Chapter 12 inMcKinney, 1988.Google Scholar
Jolicoeur, P. 1963a. The multivariate generalization of the allometry equation. Biometrics 19:497499.CrossRefGoogle Scholar
Jolicoeur, P. 1963b. The degree of generality of robustness in Martes americana. Growth 27:127.Google Scholar
Klingenberg, C. P. 1996. Multivariate allometry. Pp. 2349in Marcus, L. F., Corti, M., Loy, A., Slice, D., and Naylor, G., eds. Advances in morphometrics. Plenum, New York.CrossRefGoogle Scholar
Klingenberg, C. P., and Zimmermann, M. 1992. Static, ontogenetic, and evolutionary allometry: a multivariate comparison in nine species of water striders. American Naturalist 140:601620.CrossRefGoogle Scholar
Long, J. A., and McNamara, K. J. 1995. Heterochrony in dinosaur evolution. Pp. 151168in McNamara, K. J., ed. Evolutionary change and heterochrony. Wiley,.Google Scholar
Marcus, L. F. 1990. Traditional morphometrics. Pages 77122in Rohlf, F. J. and Bookstein, F. L., eds. Proceedings of the Michigan morphometrics workshop. University of Michigan Museum of Zoology Special Publication No. 2. Ann Arbor.Google Scholar
McKinney, M. L. 1986. Ecological causation of heterochrony: a test and implications for evolutionary theory. Paleobiology 12:282289.CrossRefGoogle Scholar
McKinney, M. L., ed. 1988. Heterochrony in evolution. Plenum, New York.CrossRefGoogle Scholar
McKinney, M. L., and McNamara, K. J. 1991. Heterochrony: the evolution of ontogeny. Plenum, New York.CrossRefGoogle Scholar
O'Keefe, F. R., and Sander, P. M. 1999. Paleontological paradigms and inferences of phylogenetic pattern: a case study. Paleobiology 25:xxxxxxCrossRefGoogle Scholar
Pimentel, R. A. 1979. Morphometrics: the multivariate analysis of biological data. Kendall/Hunt, Dubuque, Iowa.Google Scholar
Raff, R. A., and Wray, G. A. 1989. Heterochrony: developmental mechanisms and evolutionary results. Journal of Evolutionary Biology 2:409434.CrossRefGoogle Scholar
Reilly, S. M., Wiley, E. O., and Meinhardt, D. J. 1997. An integrative approach to heterochrony: the distinction between interspecific and intraspecific phenomena. Biological Journal of the Linnean Society 60:119143.CrossRefGoogle Scholar
Rice, S. H. 1997. The analysis of ontogenetic trajectories: when a change in size or shape is not heterochrony. Proceedings of the National Academy of Sciences USA 94:907912.CrossRefGoogle Scholar
Rieppel, O. 1989. A new pachypleurosaur (Reptilia: Sauropterygia) from the Middle Triassic of Monte San Giorgio, Switzerland. Philosophical Transactions of the Royal Society of London B 323:173.Google Scholar
Rieppel, O. 1994. Middle Triassic reptiles from Monte San Giorgio: recent results and future potential for analysis. In Mazin, J.-M. and Pinna, G., eds. Evolution, ecology, and biogeography of the Triassic reptiles. Paleontologia Lombarda, Milano, new series 2:131144.Google Scholar
Sander, P. M. 1989. The pachypleurosaurids (Reptilia: Nothosauria) from the Middle Triassic of Monte San Giorgio (Switzerland), with the description of a new species. Philosophical Transactions of the Royal Society of London B 325:561670.Google Scholar
Sander, P. M. 1990. Skeletochronology in the small Triassic reptile Neusticosaurus. Annales des Sciences Naturelles, Zoologie, Paris 13e Série 11:213217.Google Scholar
Schoch, R. 1995. Heterochrony in the development of the amphibian head. Pp. 107124in McNamara, K. J., ed. Evolutionary change and heterochrony. Wiley, New York.Google Scholar
Schweitzer, P. N., Kaesler, R. L., and Lohman, G. P. 1986. Ontogeny and heterochrony in the ostracode Cavellina Coryell from the Lower Permian rocks in Kansas. Paleobiology 12:290301.CrossRefGoogle Scholar
Shea, B. T. 1985. Bivariate and multivariate growth allometry: statistical and biological considerations. Journal of Zoology series A 206:367390.CrossRefGoogle Scholar
Sokal, R. R., and Rohlf, F. J. 1995. Biometry, 3d ed.W. H. Freeman, New York.Google Scholar
Stefani, M., Arduini, P., Garassino, A., Pinna, G., Teruzzi, G., and Trombetta, G. L. 1992. Paleoenvironment of extraordinary fossil biotas from the Upper Triassic of Italy. Atti della Società Italiana di Scienze Naturali 132:309335.Google Scholar
Tissot, B. N. 1988. Multivariate analysis. Chapter 3 inMcKinney, 1988.Google Scholar
Zelditch, M. L., and Fink, W. L. 1996. Heterochrony and heterotopy: stability and innovation in the evolution of form. Paleobiology 22:241254.CrossRefGoogle Scholar
Zangerl, R. 1935. Die Triasfauna der Tessiner Kalkalpen. 9. Pachypleurosaurus edwardsi Cornalia sp., Osteologie—Variationsbreite—Biologie. Abhandlungen der schweizerischen Paläontologischen Gesellschaft 56:180.Google Scholar