Skip to main content
Log in

New Studies of Enamel Microstructure in Mesozoic Mammals: A Review of Enamel Prisms as a Mammalian Synapomorphy

  • Published:
Journal of Mammalian Evolution Aims and scope Submit manuscript

Abstract

Characters from enamel microstructure have not been used in recent phylogenetic analyses of Mesozoic Mammalia. Reasons are that enamel characters have been perceived as (A) variable without regard to systematic position of taxa, (B) inconsistently reported within the literature, and (C) simply scored as either prismatic or not prismatic in earlier mammals. Our work on Mesozoic mammals such as Sinoconodon, Gobiconodon, Triconodontidae, Docodon, Laolestes, and others suggests that synapsid columnar enamel (SCE) structure was easily transformed into plesiomorphic prismatic enamel (PPE) and that PPE may be described with at least five independent character states. Two PPE characters—a flat, open prism sheath and a planar prism seam—were present in the cynodont Pachygenelus and in several Jurassic and Cretaceous mammals. We propose that appearance of a prism sheath transforms SCE into PPE and that reduction and loss of a prism sheath reverse PPE into SCE, in both phylogeny and ontogeny. We further propose that no amniote vertebrates other than the trithelodontid cynodont, Pachygenelus, plus Mammalia have ever evolved an ameloblastic Tomes process capable of secreting PPE and that the genetic potential to secrete PPE is a synapomorphy of Pachygenelus plus Mammalia, whether or not all lineages of the clade have expressed that potential.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

LITERATURE CITED

  • Birkhead, D., and Heinz, U. (1989). Salivary secretion rate, buffer capacity, and pH. In: Human Saliva: Clinical Chemistry and Microbiology, Vol. I, J. O. Tenovuo, ed., pp. 26–73, CRC Press, Boca Raton, FL.

    Google Scholar 

  • Boyde, A. C. (1964). The Structure and Development of Mammalian Enamel, Ph.D. thesis, University of London, London.

    Google Scholar 

  • Boyde, A. C. (1969). Correlation of ameloblast size with enamel prism pattern: Use of scanning electron microscope to make surface measurements. Zeitsch. Zellforsch. 93: 583–593.

    Google Scholar 

  • Boyde, A. C. (1976a). Amelogenesis and the structure of enamel. In: Scientific Foundations of Dentistry, B. Cohen and I. R. Kramer, eds., pp. 335–352, Heinemann Medical Books, London.

    Google Scholar 

  • Boyde, A. C. (1976b). Enamel structure and cavity margins. Oper. Dent. 1: 13–28.

    Google Scholar 

  • Boyde, A. C. (1980). Histological studies of the dental tissues of odontocetes. Reports Int. Whaling Comm. Spec. Issue 3: 65–87.

    Google Scholar 

  • Boyde, A. C. (1984a). Airpolishing effects on enamel, dentine, cement and bone. Br. Dent. J. 156: 287–291.

    Google Scholar 

  • Boyde, A. C. (1984b). Dependence of rate of physical erosion on orientation and density in mineralised tissues. Anat. Embryol. 170: 57–62.

    Google Scholar 

  • Caldwell, R. C., Muntz, M. L., Gilmore, R. W., and Pigman, W. (1957). Microhardness studies of intact surface enamel. J. Dent. Res. 36: 732–738.

    Google Scholar 

  • Carlson, S. J. (1990). Vertebrate dental structures. In: Skeletal Biomineralization: Patterns, Processes, and Evolutionary Trends, J. G. Carter, ed., pp. 531–556, Van Nostrand Reinhold, New York.

    Google Scholar 

  • Carlson, S. J., and Krause, D. W. (1985). Enamel ultrastructure of multituberculate mammals: An investigation of variability. Contrib. Mus. Paleo. Univ. Mich. 27: 1–50.

    Google Scholar 

  • Cifelli, R. L. (1993). Early Cretaceous mammal from North America and the evolution of marsupial dental characters. Proc. Natl. Acad. Sci. USA 90: 9413–9416.

    Google Scholar 

  • Cifelli, R. L., Wible, J. R., and Jenkins, F. A., Jr. (1998). Triconodont mammals from the Cloverly Formation (Lower Cretaceous), Montana and Wyoming. J. Vert. Paleo. 18: 237–241.

    Google Scholar 

  • Clemens, W. A. (1979). Marsupialia. In: Mesozoic Mammals: The First Two-Thirds of Mammalian History, J. A. Lillegraven, Z. Kielan-Jaworowska, and W. A. Clemens, eds., pp. 192–220, University of California Press, Berkeley.

    Google Scholar 

  • Clemens, W. A. (1997). Characterization of enamel microstructure and application of the origins of prismatic structures in systematic analyses. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 85–112, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Cooper, J. S., and Poole, D. F. G. (1973). The dentition and dental tissues of the agamid lizard, Uromastyx. J. Zool. 169: 85–100.

    Google Scholar 

  • Crompton, A. W. (1972). Postcanine occlusion in cynodonts and tritylodontids. Bull. Br.Mus. Nat. Hist. Geol. 21: 27–71.

    Google Scholar 

  • Crompton, A. W. (1995). Masticatory function in nonmammalian cynodonts and early mammals. In: Functional Morphology in Vertebrate Paleontology, J. J. Thomason, ed., pp. 55–75, Cambridge University Press, Cambridge.

    Google Scholar 

  • Crompton, A. W., and Jenkins, F. A., Jr. (1968). Molar occlusion in late Triassic mammals. Biol. Rev. 43: 427–458.

    Google Scholar 

  • Crompton, A. W., and Luo, Z. (1993). Relationships of the Liassic mammals, Sinoconodon, Morganucodon oehleri, and Dinnetherium. In: Mammal Phylogeny, F. S. Szalay, M. J. Novacek, and M. C. McKenna, eds., pp. 30–44, Springer-Verlag, New York.

    Google Scholar 

  • Crompton, A. W., Wood, C. B., and Stern, D. N. (1994). Differential wear of enamel: A mechanism for maintaining sharp cutting edges. In: Advances in Comparative and Environmental Physiology, 18, V. L. Bels, M. Chardon, and P. Vandewalle, eds., pp. 321–346, Springer-Verlag, Berlin, Heidelberg.

    Google Scholar 

  • Dumont, E. R. (1993). Functional and Phyletic Features of Mammalian Dental Enamel: A Key to Primate Higher-Level Relationships, Ph.D. thesis, State University of New York, Stony Brook.

    Google Scholar 

  • Dumont, E. R. (1997). Salivary pH and buffering capacity in frugivorous and insectivorous bats. J. Mamm. 78: 1210–1219.

    Google Scholar 

  • Dumont, E. R., Strait, S. G., and Overdorff, D. J. (1997). Oral pH in fruit, leaf and insect-feeding primates and bats. Am. J. Phys. Anthropol. Suppl. 24: 103.

    Google Scholar 

  • Fortelius, M. (1985). Ungulate cheek teeth: Developmental, functional and evolutionary interrelations. Acta. Zool. Fenn. 180: 1–76.

    Google Scholar 

  • Fosse, G., Kielan-Jaworowska, Z., and Skalle, S. (1985). The microstructure of tooth enamel in multituberculate mammals. Palaeontology 28: 435–449.

    Google Scholar 

  • Frank, R. M. (1990). Structural events in the caries process in enamel, cementum and dentine. J. Dent. Res. Spec. Issue 69: 559–566.

    Google Scholar 

  • Frank, R. M., Sigogneau-Russell, D., and Hemmerle, J. (1988). Ultrastructural study of triconodont (Prototheria, Mammalia) teeth from the Rhaeto-Liassic. Teeth Revisited: Proceedings of the VIIth International Symposium on Dental Morphology, Paris 1986, D. Russell, J. Santoro, and D. Sigogneau-Russell, eds., pp. 101–108, Mem. Mus. Nat. Hist. Nat., Paris (Ser. C), 53.

  • Gibbons, A. (1998). Genes put mammals in Age of Dinosaurs. Science 280: 675–676.

    Google Scholar 

  • Grine, F. E. (1986). Effects of different etching agents on bovid tooth enamel. S. Afr. J. Sci. 82: 265–270.

    Google Scholar 

  • Grine, F. E., and Vrba, E. S. (1980). Prismatic enamel: A pre-adaptation for mammalian diphyodonty? S. Afr. J. Sci. 76: 139–141.

    Google Scholar 

  • Grine, F. E., Krause, D. W., Fosse, G., and Jungers, W. L. (1987). Analysis of individual, intraspecific and interspecific variability in quantitative parameters of caprine tooth enamel structure. Acta. Odontol. Scand. 45: 1–23.

    Google Scholar 

  • Grobler, S. R. (1991). The effect of a high composition of citrus fruit and a mixture of other fruits on dental caries in man. Clin. Prev. Dent. 13: 13–17.

    Google Scholar 

  • Gwinnett, A. J. (1967). The structure of the “prismless” enamel of permanent human teeth. Arch. Oral Biol. 12: 381–387.

    Google Scholar 

  • Gwinnett, A. J. (1992). Structure and composition of enamel. Oper. Dent. Suppl. 5: 10–17.

    Google Scholar 

  • Haikel, Y., Frank, R. M., and Voegel, J. C. (1983). Scanning electron microscopy of the human enamel surface layer of incipient carious lesions. Caries Res. 17: 1–13.

    Google Scholar 

  • Hodge, H. C., and McKay, J. H. (1933). The microhardness of human teeth. J. Am. Dent. Assoc. 20: 227–233.

    Google Scholar 

  • Hu, Y., Wang, Y., Luo, Z., and Li, C. (1997). A new symmetrodont mammal from China and its implications for mammalian evolution. Nature 390: 137–142.

    Google Scholar 

  • Ichijo, T., Yamashita, Y., and Terashima, T. (1992). Observations on the structural features and characteristics of biological apatite crystals. 2. Observations on the structure of human enamel crystals. Bull. Tokyo Med. Dent. Univ. 39: 71–80.

    Google Scholar 

  • Ishiyama, M. (1984). Comparative histology of tooth enamel in several toothed whales. In: Tooth Enamel IV, R. W. Fearnhead and S. Suga, eds., pp. 432–436, Elsevier Science, Amsterdam.

    Google Scholar 

  • Ishiyama, M. (1987). Enamel structure in odontocete whales. Scann. Microsc. 1: 1071–1079.

    Google Scholar 

  • Jenkins, F. A., Jr. (1969). Occlusion in Docodon (Mammalia, Docodonta). Postilla Yale Peabody Mus. 139: 1–24.

    Google Scholar 

  • Jenkins, F. A., Jr., and Schaff, C. R. (1988). The early Cretaceous mammal Gobiconodon (Mammalia, Triconodonta) from the Cloverly Formation in Montana. J. Vert. Paleo. 8: 1–24.

    Google Scholar 

  • Jenkins, F. A., Jr., Gatesy, S. M., Shubin, N. H., and Amaral, W. W. (1997). Haramiyids and Triassic mammalian evolution. Nature 385: 715–718.

    Google Scholar 

  • Kielan-Jaworowska, Z. (1977). Results of the Polish-Mongolian palaeontological expeditions. Part VII. Evolution of the therian mammals in the Late Cretaceous of Asia. Part II. Postcranial skeleton in Kennalestes and Asioryctes. Palaeo. Polonica 37: 65–83.

    Google Scholar 

  • Kielan-Jaworowska, Z. (1979). Results of the Polish-Mongolian palaeontological expeditions. Part VII. Evolution of the therian mammals in the Late Cretaceous of Asia. Part III. Postcranial skeleton in Zalambdalestidae. Palaeo. Polonica 38: 3–41.

    Google Scholar 

  • Kielan-Jaworowska, Z., and Nessov, L. (1990). On the metatherian nature of the Deltatheroida, a sister group of the marsupials. Lethaia 23: 1–10.

    Google Scholar 

  • Koenigswald, W. (1980). Schmelzstruktur und Morphologie in den Molaren der Avricolidae (Rodentia). Abh. Senck. Naturf. Gesells. Frankfurt 539: 1–129.

    Google Scholar 

  • Koenigswald, W. (1988). Enamel modification in enlarged front teeth among mammals and the various possible reinforcements of the enamel. In: Teeth Revisited: Proceedings of the VIIth International Symposium on Dental Morphology, D. E. Russell, J. P. Santoro, and D. Sigogneau-Russell, eds., pp. 147–167, Mem. Mus. Nat. Hist. Nat. C53, Paris.

  • Koenigswald, W. (1994). Differenzierungen im Zahnschmelz der Marsupialia im Vergleich zu den Verhaeltnissen bei den Placentalia (Mammalia). Berl. Geowis. Abh. Krebs Festschr. E13: 45–81.

    Google Scholar 

  • Koenigswald, W. (1997). Evolutionary trends in the differentiation of mammalian enamel ultrastructure. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 203–231, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Koenigswald, W., and Clemens, W. A. (1992). Levels of complexity in the microstructure of mammalian enamel and their application in studies of systematics. Scann. Microsc. 6: 195–218.

    Google Scholar 

  • Koenigswald, W., and Sander, P. M. (eds.) (1997a). Tooth Enamel Microstructure, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Koenigswald, W., and Sander, P. M. (1997b). Glossary of terms used for enamel microstructures. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 267–280, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Koenigswald, W., Martin, T., and Pfretzschner, H. U. (1993). Phylogenetic interpretations of enamel structures in mammalian teeth: Possibilities and problems. In: Mammalian Phylogeny 2, F. S. Szalay, M. J. Novacek, and M. C. McKenna, eds., pp. 303–314, Springer Verlag, New York/Berlin.

    Google Scholar 

  • Krause, D. W., and Carlson, S. J. (1986). The enamel ultrastructure of multituberculate mammals—A review. Scann. Elec. Microsc. IV: 1591–1607.

    Google Scholar 

  • Krebs, B. (1991). Das Skelett von Henkelotherium guimarotae gen. et sp. nov. (Eupantotheria, Mammalia) aus dem Oberen Jura von Portugal. Berl. Geowis. Abh. R. A B. 133: 1–110.

    Google Scholar 

  • Lester, K. S. (1989). Procerberus enamel—A missing link. Scann. Microsc. 3: 639–644.

    Google Scholar 

  • Lester, K. S., and Boyde, A. (1986). Scanning electron microscopy of platypus teeth. Anat. Embryol. 174: 15–26.

    Google Scholar 

  • Lester, K. S., Boyde, A., Gilkeson, C., and Archer, M. (1987). Marsupial and monotreme enamel. Scann. Microsc. 1: 401–420.

    Google Scholar 

  • Lester, K. S., and Hand, S. J. (1987). Chiropteran enamel structure. Scann. Microsc. 1: 421–436.

    Google Scholar 

  • Lester, K. S., Hand, S. J., and Vincent, F. (1988). Adult phyllostomid (bat) enamel by scanning electron microscopy—With a note on dermopteran enamel. Scann. Microsc. 2: 371–383.

    Google Scholar 

  • Lester, K. S., and Koenigswald, W. (1989). Crystallite orientation discontinuities, and the evolution of mammalian enamel—or, when is a prism? Scann. Microsc. 3: 645–663.

    Google Scholar 

  • Lillegraven, J. A., and Krusat, G. (1991). Cranio-mandibular anatomy of Haldanodon exspectatus (Docodonta; Mammalia) from the Late Jurassic of Portugal and its implications to the evolution of mammalian characters. Contrib. Geol. Univ. Wyo. 28: 39–138.

    Google Scholar 

  • Lillegraven, J. A., Kielan-Jaworowska, Z., and Clemens, W. A. (eds.) (1979). Mesozoic Mammals: The First Two-Thirds of Mammalian History, University of California Press, Berkeley.

    Google Scholar 

  • Lucas, S. G., and Luo, Z. (1993). Adelobasileus from the Upper Triassic of West Texas: The oldest mammal. J. Vert. Paleo. 13: 309–334.

    Google Scholar 

  • Luo, Z. (1994). Sister-group relationships of mammals and transformations of diagnostic mammalian characters. In: In the Shadow of the Dinosaurs—Early Mesozoic Tetrapods, N. C. Fraser and H.-D. Sues, eds., pp. 98–128, Cambridge University Press, Cambridge.

    Google Scholar 

  • Maas, M. C. (1991). Enamel structure and microwear: An experimental study of the response of enamel to shearing force. Am. J. Phys. Anthropol. 85: 31–49.

    Google Scholar 

  • Maas, M. C. (1993). Enamel microstructure and molar wear in the greater galago, Otolemur crassicaudatus (Mammalia, Primates). Am. J. Phys. Anthropol. 92: 217–233.

    Google Scholar 

  • Maas, M. C. (1994). Enamel microstructure in Lemuridae (Mammalia, Primates): Assessment of variability. Am. J. Phys. Anthropol. 95: 221–241.

    Google Scholar 

  • Maas, M. C., and Thewissen, J. G. M. (1995). Enamel microstructure of Pakicetus (Mammalia: Archaeoceti). J. Paleontol. 69: 1154–1163.

    Google Scholar 

  • Marshall, L., and Kielan-Jaworowska, Z. (1992). Relationships of the dog-like marsupials, deltatheroidans, and early tribosphenic mammals. Lethaia 25: 1–15.

    Google Scholar 

  • Martin, L. M. (1983). The Relationships of the Later Miocene Hominoidea, Ph.D. thesis, University College London, London.

    Google Scholar 

  • Martin, L. M., Boyde, A. C., and Grine, F. E. (1988). Enamel structure in primates: A review of scanning electron microscope studies. Scann. Microsc. 2: 1503–1526.

    Google Scholar 

  • Meurman, J. H., and ten Cate, J. M. (1996). Pathogenesis and modifying factors of dental erosion. Eur. J. Or. Sci. 104: 199–206.

    Google Scholar 

  • Moss, M. L. (1969). Evolution of mammalian dental enamel. Am. Mus. Novit. 2360: 1–39.

    Google Scholar 

  • Nelson, D. G. A. (1990). Backscattered electron imaging of partially-demineralized enamel. Scann. Microsc. 4: 31–42.

    Google Scholar 

  • Newbrun, E. (1989). Cardiology, 3rd ed., Quintessence Books, Chicago.

    Google Scholar 

  • Newbrun, E., and Pigman, W. (1960). The hardness of enamel and dentine. Austr. Dent. J. 5: 210–217.

    Google Scholar 

  • Novacek, M. J., Rougier, G. W., Wible, J. R., McKenna, M. C., Dashzeveg, D., and Horovitz, I. (1997). Epipubic bones in eutherian mammals from the late Cretaceous of Mongolia. Nature 389: 483–486.

    Google Scholar 

  • Nunn, J. H. (1996). Prevalence of dental erosion and implications for oral health. Eur. J. Or. Sci. 104: 156–161.

    Google Scholar 

  • Owen, R. (1845). Odontography, 2 vols. Hippolyte Bailiere, London.

    Google Scholar 

  • Pfretzschner, H. U. (1992). Enamel structure and hypsodonty in large mammals. In: Structure, Function, and Evolution of Teeth, P. Smith and E. Tchernov, eds., pp. 147–162, Freund, London/Tel Aviv.

    Google Scholar 

  • Pfretzschner, H. U. (1994). Biomechanik der Schmelzmikrostruktur in den Backenzahne ihren von Grossaugern. Palaeontographica A 234: 1–88.

    Google Scholar 

  • Poole, D. F. G. (1971). An introduction to the phylogeny of calcified tissues. In: Dental Morphology and Evolution, A. A. Dahlberg, ed., pp. 65–79, University of Chicago Press, Chicago.

    Google Scholar 

  • Prothero, D. R. (1981). New Jurassic mammals from Como Bluff, Wyoming, and the interrelationships of non-tribosphenic Theria. Bull. Am. Mus. Nat. Hist. 167(5): 281–325.

    Google Scholar 

  • Reig, O. A., Kirsch, J. A. W., and Marshall, L. G. (1987). Systematic relationships of the living and Neocenozoic American “opossum-like” marsupials (Suborder Didelphimorphia), with comments on the classification of these and of the Cretaceous and Paleogene New World and European metatherians. In: Possums and Opossums: Studies in Evolution, Vol. 1, Royal Zoological Society of New South Wales, M. Archer, ed., pp. 1–89, Surrey Beatty and Sons, Sydney.

    Google Scholar 

  • Rensberger, J. M. (1992). Relationship of chewing stress and enamel microstructure in rhinoceratoid cheek teeth. In: Structure, Function, and Evolution of Teeth, P. Smith and E. Tchernov, eds., pp. 163–183, Freund, London/Tel Aviv.

    Google Scholar 

  • Rensberger, J. M. (1995). Determination of stresses in mammalian dental enamel and their relevance to the interpretation of feeding behaviors in extinct taxa. In: Functional Morphology in Vertebrate Paleontology, J. J. Thomason, ed., pp. 151–172, Cambridge University Press, Cambridge.

    Google Scholar 

  • Rensberger, J. M. (1997). Mechanical adaptation in enamel. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 237–257, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Rensberger, J. M. (1999). Enamel microstructural specializations in the canine of the spotted hyena, Crocuta crocuta. Scann. Microsc. (in press).

  • Ripa, L. W., Gwinnett, A. J., and Bunocore, M. G. (1966). The “prismless” outer layer of deciduous and permanent teeth. Arch. Oral Biol. 11: 41–48.

    Google Scholar 

  • Rougier, G. W., Wible, J. R., and Hopson, J. A. (1996). Basicranial anatomy of Priacodon fruitaensis (Triconodontidae, Mammalia) from the Late Jurassic of Colorado, and a reappraisal of mammaliaform interrelationships. Am. Mus. Novit. 3183: 1–38.

    Google Scholar 

  • Rowe, T. (1988). Definition, diagnosis, and origin of Mammalia. J. Vert. Paleo. 8: 241–264.

    Google Scholar 

  • Saether, O. L. (1979). Underlying synapomorphies and anagenic analysis. Zool. Scripta 8: 305–312.

    Google Scholar 

  • Sahni, A. (1979). Enamel ultrastructure of certain North American Cretaceous mammals. Palaeontographica A 166: 37–49.

    Google Scholar 

  • Sahni, A., and Koenigswald, W. (1997). The enamel structure of some fossil and recent whales from the Indian subcontinent. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 177–191, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Sander, P. M. (1997). Non-mammalian synapsid enamel and the origin of mammalian enamel prisms: The bottom-up perspective. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 41–62, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Shellis, R. P., and Hallsworth, A. S. (1987). The use of scanning electron microscopy in study enamel caries. Scann. Microsc. 1: 1109–1123.

    Google Scholar 

  • Shubin, N. H., Crompton, A. W., Sues, H. D., and Olsen, P. E. (1991). New fossil evidence on the sister-group of mammals and early Mesozoic faunal distributions. Science 251: 1063–1065.

    Google Scholar 

  • Sidor, C. A., and Hopson, J. A. (1998). Ghost lineages and “mammalness”: Assessing the temporal pattern of character acquisition in the Synapsida. Paleobiology 24: 254–273.

    Google Scholar 

  • Sigogneau-Russell, D., Frank, D. R., and Hemmerle, J. (1984). Enamel and dentine ultrastructure in the early Jurassic therian Kuehneotherium. Zool. J. Linn. Soc. 82: 207–215.

    Google Scholar 

  • Simmons, N. B. (1993). Phylogeny of Multituberculata. In: Mammal Phylogeny, F. S. Szalay, M. J. Novacek, and M. C. McKenna, eds., pp. 146–164, Springer-Verlag, New York.

    Google Scholar 

  • Sorvari, R., Pelttari, A., and Meurman, J. H. (1996). Surface ultrastructure of rat molar teeth after experimentally-induced erosion and attrition. Caries Res. 30: 163–168.

    Google Scholar 

  • Stern, D. N. (1989). The Structure, Function, and Development of Primitive Mammalian Enamel, Ph.D. thesis, Harvard University, Cambridge, MA.

    Google Scholar 

  • Stern, D. N., and Crompton, A. W. (1995). A study of enamel organization, from reptiles to mammals. In: Aspects of Dental Biology: Paleontology, Anthropology, and Evolution, J. Moggi-Cecchi, ed., Proceedings of the Ninth International Symposium on Dental Morphology, Florence, Italy, September 3–6, 1992, pp. 1–25, International Institute for the Study of Man, Florence.

    Google Scholar 

  • Stern, D. N. Crompton, A. W., and Skobe, Z. (1989). Enamel ultrastructure and masticatory function in molars of the American opossum, Didelphis virginiana. Zool. J. Linn. Soc. 95: 311–334.

    Google Scholar 

  • Tomes, J. (1849). On the structure of the dental tissues of marsupials, and more especially of the enamel. Phil. Trans. Roy. Soc. Lond. 139: 403.

    Google Scholar 

  • Ungar, P. S. (1995). Fruit preferences of four sympatric primate species at Ketambe, northern Sumatra, Indonesia. Int. J. Primatol. 16: 221–245.

    Google Scholar 

  • Wakita, M., and Kobayashi, S. (1983). The three dimensional structure of the Tomes processes and the development of the microstructural organization of tooth enamel. In: Mechanisms of Tooth Enamel Formation, S. Suga, ed., pp. 65–89, Quintessence, Tokyo.

    Google Scholar 

  • Werth, A. J., and Stern, D. N. (1992). Functional influences in the evolution and devolution of odontocete enamel. J. Vert. Paleo. 12: 59A.

    Google Scholar 

  • Wible, J. R. (1991). Origin of Mammalia: The craniodental evidence reexamined. J. Vert. Paleo. 11: 1–28.

    Google Scholar 

  • Wood, C. B. (1992). Comparative Studies of Enamel and Functional Morphology in Selected Mammals with Tribosphenic Molar Teeth: Phylogenetic Applications, Ph.D. thesis, Harvard University, Cambridge, MA.

    Google Scholar 

  • Wood, C. B., and Stern, D. N. (1997). The earliest prisms in reptilian and mammalian enamel. In: Tooth Enamel Microstructure, W. Koenigswald and P. M. Sander, eds., pp. 63–83, A. A. Balkema, Rotterdam.

    Google Scholar 

  • Zero, D. T. (1996). Etiology of dental erosion—Extrinsic factors. Eur. J. Or. Sci. 104: 162–177.

    Google Scholar 

  • Zikui, Z., and Wending, Z. (1991). Ultrastructure of triconodont teeth. Vert. Palasiat. 29: 72–79.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to C. B. Wood.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Wood, C.B., Dumont, E.R. & Crompton, A.W. New Studies of Enamel Microstructure in Mesozoic Mammals: A Review of Enamel Prisms as a Mammalian Synapomorphy. Journal of Mammalian Evolution 6, 177–213 (1999). https://doi.org/10.1023/A:1020624222324

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1020624222324

Navigation