Growth-invariant Meristic Characters Tools to Reveal Phylogenetic Relationships in Nummulitidae (Foraminifera)

Morphological characters that are restricted to a few growth-independent characters (such as the embryonic apparatus of nummulitids) or measurements at arbitrarily chosen growth stages (such as the second whorl in planispiral tests) do not adequately explain the phylogenetic relationships of fossil forms. Molecular-genetic investigations enlighten phylogenetic relations, but have two main disadvantages. First, they are restricted to living forms, and second, these relations are based on an extremely small part of the DNA and never on developmental and structural genes that regulate morphology. Morphometric methods based on growth-invariant characters allow modelling the test shape for each growth stage and thus point to the underlying complex of regulatory and structural genes responsible for shape and size. They can therefore be used in fossil forms. Growth-independent and growth-invariant parameters were developed to model planispirally enrolled tests using living nummulitids from the West Pacific, where the molecular genetic relations are known. Discriminant analyses based on growth-invariant parameters demonstrate a perfect correlation with biological species. The taxonomic distances (Mahalanobis Distance) indicate phylogenetic relationships and agree well with molecular-genetic relations. The exception is the strong misclassification of the only living representative (Palaeonummulites) of the important fossil Nummulites-group by molecular genetic methods: that approach places this species with the morphologically completely distinct Planostegina-group. The close morphological relation between O. dicoidalis and O. ammonoides and between O. elegans and O. complanata, both supported by molecular genetic investigation, is an argument for being ecophenotypes of the two biological species O. ammonoides and O. complanata. The use of growth-invariant variables and characters can thus be today's strongest tool to shed light on phylogenetic relationships in fossil forms.

Growth-invariant Meristic Characters Tools to Reveal Phylogenetic Relationships in Nummulitidae (Foraminifera)

Morphological characters that are restricted to a few growth-independent characters (such as the embryonic apparatus of nummulitids) or measurements at arbitrarily chosen growth stages (such as the second whorl in planispiral tests) do not adequately explain the phylogenetic relationships of fossil forms. Molecular-genetic investigations enlighten phylogenetic relations, but have two main disadvantages. First, they are restricted to living forms, and second, these relations are based on an extremely small part of the DNA and never on developmental and structural genes that regulate morphology. Morphometric methods based on growth-invariant characters allow modelling the test shape for each growth stage and thus point to the underlying complex of regulatory and structural genes responsible for shape and size. They can therefore be used in fossil forms. Growth-independent and growth-invariant parameters were developed to model planispirally enrolled tests using living nummulitids from the West Pacific, where the molecular genetic relations are known. Discriminant analyses based on growth-invariant parameters demonstrate a perfect correlation with biological species. The taxonomic distances (Mahalanobis Distance) indicate phylogenetic relationships and agree well with molecular-genetic relations. The exception is the strong misclassification of the only living representative (Palaeonummulites) of the important fossil Nummulites-group by molecular genetic methods: that approach places this species with the morphologically completely distinct Planostegina-group. The close morphological relation between O. dicoidalis and O. ammonoides and between O. elegans and O. complanata, both supported by molecular genetic investigation, is an argument for being ecophenotypes of the two biological species O. ammonoides and O. complanata. The use of growth-invariant variables and characters can thus be today's strongest tool to shed light on phylogenetic relationships in fossil forms.

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  • Banner, F.T. & Hodgkinson, R.L. 1991. A Revision of the foraminferal subfamily Heterostegininae. Revista Espaňola de Micropaleontolgia 23, 101–140.
  • Drooger, C.W. & Roelofsen, J.W. 1982. Cycloclypeus from Ghar Hassan, Malta. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen (B) 85, 203–218.
  • Drooger, C.W., Marks, P. & Papp, A. 1971. Smaller radiate Nummulites of Northwestern Europe. Utrecht Micropaleontological Bulletin 5, 1–137.
  • Fermont, W.J.J. 1977a. Biometrical investigation of the genus Operculina in Recent Sediments of the Gulf of Elat. Utrecht Micropaleontological Bulletin 15, 111–147.
  • Fermont, W.J.J. 1977b. Depth-gradients in internal parameters of Heterostegina in the Gulf of Elat. Utrecht Micropaleontological Bulletin 15, 149–163.
  • Hammer, Ø., Harper, D.A.T. & Ryan, P.D. 2001. PAST: Paleontological Statistics Soft ware Package for Education and Data Analysis. Palaeontologia Electronica 4.
  • Hayward, B.W., Holzmann, M., Grenfell, H.R., Pawlowski, J. & Triggs, C.M. 2004. Morphological distinction of molecular types in Ammonia – towards a taxonomic revsion of the world’s most commonly misidentifi ed foraminifera. Marine Mixropaleontology 50, 237–271.
  • Hohenegger, J. 1990. On the way to the optimal suprageneric classifi cation of agglutinating Foraminifera. In: Hemleben, C., Kaminski, M., Kuhnt, W. & Scott, D.B. (eds), Paleoecology, Biostratigraphy, Paleoceanography and Taxonomy of Agglutinated Foraminifera. Kluwer Academic Publishers, Amsterdam, 77–104.
  • Hohenegger, J. 1994. Determination of Upper Triassic and Lower Jurassic Ichthyolarias using morphogenetic programs. Micropaleontology 39, 233–262.
  • Hohenegger, J. 2000. Coenoclines of larger foraminifera. Micropaleontology 46, supplement no. 1, 127–151.
  • Hohenegger, J. 2004. Depth coenoclines and environmental considerations of Western Pacifi c larger foraminifera. Journal of Foraminiferal Research 34, 9–33.
  • Hohenegger, J. & Tatzreiter, F. 1992. Morphometric methods in determination of ammonite species, exemplifi ed through Balatonites shells (Middle Triassic). Journal of Paleontology 66, 801–816.
  • Hohenegger, J., Yordanova, E. & Hatta, A. 2000. Remarks on West Pacifi c Nummulitidae (Foraminifera). Journal of Foraminiferal Research 30, 3–28.
  • Holzmann, M., Hohenegger, J. & Pawlowski, J. 2003. Molecular data reveal parallel evolution in nummulitid Foraminifera. Journal of Foraminiferal Research 33, 8–15.
  • Krzanowski, W.J. & Marriott, F.H.C. 1995. Multivariate Analysis. Part 2. Classifi cation, Covariance Structures and Repeated Measurements. Arnold, London.
  • Less, G., Özcan, E., Papazzoni, C.A. & Stockar, R. 2008. Th e middle to late Eocene evolution of nummulitid foraminifer Heterostegina in the Western Tethys. Acta Palaeontologica Polonica 53, 317–350.
  • Mayr, E. & Ashlock, P.D. 1991. Principles of Systematic Zoology. McGraw-Hill, New York.
  • Özcan, E., Less, G., Báldi-Beke, M., Kollányi, K. & Acar, F. 2009. Oligo–Miocene foraminiferal record (Miogypsinidae, Lepidocyclinidae and Nummulitidae) from the Western Taurides (SW Turkey): biometry and implications for the regional geology. Journal of Asian Earth Sciences 34, 740–760.
  • Pecheux, M.J.F. 1995. Ecomorphology of a recent large foraminifer, Operculina ammonoides. Geobios 28, 529–566.
  • Schaub, H. 1981. Nummulites et Assilines de la Tèthys paléogène. Taxinomie, phylogénese et biostratigraphie. Mémoires Suisses de Paléontologie 104-106.
  • Serra-Kiel, J., Hottinger, L., Caus, E., Drobne, K., Ferrandez, C., Jauhri, A.K., Less, G., Pavlovec, R., Pignatti, J.S., Samso, J.M., Schaub, H., Sirel, E., Strougo, A., Tambareau, Y., Tosquella, J. & Zakrevskaya, E. 1998. Biostratigraphy of the Tethyan Paleocene and Eocene. Bulletin Societe géologique de France 129, 1–19.
  • Sneath, P.H.A. & Sokal, R.R. 1973. Numerical Taxonomy. W.H. Freeman and Company, San Francisco.
  • SPSS 15.0.1 for Windows 2006.
  • Yordanova, E.K. & Hohenegger, J. 2004. Morphocoenoclines of living operculinid foraminifera based on quantitative characters. Micropaleontology 50, 149–177.