Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T07:28:39.221Z Has data issue: false hasContentIssue false
  • English
  • Français

Enamel microstructure of Pakicetus (Mammalia: Archaeoceti)

Published online by Cambridge University Press:  14 July 2015

Mary C. Maas  and
J. G. M. Thewissen
Mary C. Maas
Affiliation:
Department of Biological Anthropology and Anatomy, Duke University Medical Center, Durham, North Carolina 27710
J. G. M. Thewissen
Affiliation:
Department of Biological Anthropology and Anatomy, Duke University Medical Center, Durham, North Carolina 27710
Get access Rights & Permissions [Opens in a new window]

Abstract

The tooth enamel of the earliest cetacean, Pakicetus, is described and compared to enamel of a primitive artiodactyl and a variety of primitive ungulate families. Pakicetus enamel organization, which is considered primitive for Cetacea, consists of a combination of radial and decussating enamel types. Prism patterns include prisms with open (horseshoe-shaped) and closed (circular) boundaries. Pakicetus enamel is similar to that of many primitive ungulates, including Diacodexis, the earliest artiodactyl, and Mesonychidae, an archaic ungulate family that often is considered close to the ancestry of Cetacea. This finding is consistent with the hypothesis, originally proposed on the basis of other aspects of morphology, that artiodactyls, cetaceans, and Mesonychidae are closely related.

Type
Research Article
Information
Journal of Paleontology , Volume 69 , Issue 6 , November 1995 , pp. 1154 - 1163
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

Barnes, L. G., and Mitchell, E. 1978. Cetacea, p. 582–602. In Maglio, V. G. and Cooke, H. B. S. (eds.), Evolution of African Mammals. Harvard University Press, Cambridge, Massachusetts.Google Scholar
Barnes, L. G., Domning, D. P., and Ray, C. E. 1985. Status of studies on fossil marine mammals. Marine Mammal Science, 1:15–53.CrossRefGoogle Scholar
Boyde, A. 1969. Correlation of ameloblast size with enamel prism pattern: use of scanning electron microscope to make surface area measurements. Zeitschrift für Zellforschung, 93:583–593.Google Scholar
Boyde, A. 1971. Comparative histology of mammalian teeth, p. 81–94. In Dahlberg, A. A. (ed.), Dental Morphology and Evolution. The University of Chicago Press, Chicago, Illinois.Google Scholar
Boyde, A. 1980. Histological studies of dental tissues of odontocetes. Report of the International Whaling Commission, Special Issue 3:65–87.Google Scholar
Carlson, S. J., and Krause, D. W. 1985. Enamel ultrastructure in multituberculate mammals: an investigation of variability. Contributions from the Museum of Paleontology, the University of Michigan, 27:1–50.Google Scholar
Carter, J. T. 1948. Comparison of the microscopic structure of the enamel in the teeth of Zeuglodon osiris Dames, and of Prosqualodon davidi Flynn. Proceedings of the Zoological Society of London, 26 Part II:192–193.Google Scholar
Cifelli, R. L. 1983. The origin and affinities of the South American Condylarthra and early Tertiary Litopterna (Mammalia). American Museum Novitates, 2772:1–49.Google Scholar
Eisenmann, D. R. 1980. Enamel Structure, p. 194–217. In Ten Cate, A. R. (ed.), Oral Histology. Development, Structure, and Function. The C. V. Mosby Company, St. Louis, Missouri.Google Scholar
Flower, W. H. 1883. On whales, present and past and their probable origin. Proceedings of the Zoological Society of London, 1883:466–513.Google Scholar
Fordyce, R. E. 1992. Cetacean evolution and Eocene/Oligocene environments, p. 368–381. In Prothero, D. R. and Berggren, W. A. (eds.), Eocene-Oligocene Climatic and Biotic Evolution. Princeton University Press, Princeton, New Jersey.Google Scholar
Fosse, G. 1968a. A quantitative analysis of the numerical density and the distributional pattern of prisms and ameloblasts in dental enamel and tooth germs. III. The calculation of prism diameters and numbers of prisms per unit area in dental enamel. Acta Odontologica Scandinavica, 26:315–336.Google Scholar
Fosse, G. 1968b. A quantitative analysis of the numerical density and the distributional pattern of prisms and ameloblasts in dental enamel and tooth germs. IV. The vertical compression of the prism pattern on the outer enamel surface of human permanent teeth. Acta Odontologica Scandinavica, 26:545–572.Google Scholar
Gingerich, P. D., and Russell, D. E. 1981. Pakicetus inachus, a new archaeocete (Mammalia, Cetacea) from the early-middle Eocene Kuldana Formation of Kohat (Pakistan). Contributions from the Museum of Paleontology, the University of Michigan, 25:235–246.Google Scholar
Gingerich, P. D., and Russell, D. E. 1990. Dentition of early Eocene Pakicetus (Mammalia, Cetacea). Contributions from the Museum of Paleontology, the University of Michigan, 28:1–20.Google Scholar
Gingerich, P. D., Wells, N. A., Russell, D. E., and Shah, S. M. I. 1983. Origin of whales in epicontinental remnant seas: new evidence from the early Eocene of Pakistan. Science, 220:403–406.Google Scholar
Gingerich, P. D., Smith, B. H., and Simons, E. L. 1990. Hind limbs of Eocene Basilosaurus: evidence of feet in whales. Science, 249:154–157.Google Scholar
Goodman, M., Czelusniak, J., and Beeber, J. E. 1985. Phylogeny of primates and other eutherian orders: a cladistic analysis using amino acid and nucleotide sequence data. Cladistics, 1:171–185.Google Scholar
Graur, D. 1993. Molecular phylogeny and the higher classification of eutherian mammals. Trends in Ecology and Evolution, 8:141–147.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 Odontologica Scandinavica, 45:1–23.Google Scholar
Hohn, A. A. 1980. Analysis of growth layers in the teeth of Tursiops truncatus using light microscopy, microradiography, and SEM. Report of the International Whaling Commission, Special Issue 3:155–160.Google Scholar
Ishiyama, M. 1984. Comparative histology of tooth enamel in several toothed whales, p. 432–436. In Fearnhead, R. W. and Suga, S. (eds.), Tooth Enamel IV. Elsevier Science Publishers, Amsterdam.Google Scholar
Ishiyama, M. 1987. Enamel structure in odontocete whales. Scanning Microscopy, 1:1071–1079.Google Scholar
Koenigswald, W. V., and Clemens, W. A. 1992. Levels of complexity in the microstructure of mammalian enamel and their application in studies of systematics. Scanning Microscopy, 6:195–218.Google Scholar
Koenigswald, W. V., Rensberger, J. M., and Pfretzschner, H. U. 1987. Changes in the tooth enamel of early Paleocene mammals allowing increased diet diversity. Nature, 328:150–152.CrossRefGoogle Scholar
Kozawa, Y. 1984. The development and the evolution of mammalian enamel structure, p. 437–441. In Fearnhead, R. W. and Suga, S. (eds.), Tooth Enamel IV. Elsevier Science Publishers, Amsterdam.Google Scholar
Krause, D. W., and Carlson, S. J. 1987. Prismatic enamel in multituberculate mammals: tests of homology and polarity. Journal of Mammalogy, 68:755–765.Google Scholar
Lester, K. S., and Koenigswald, W. v. 1989. Crystallite orientation discontinuities and the evolution of mammalian enamel—or, when is a prism? Scanning Microscopy, 3:645–663.Google Scholar
Maas, M. C. 1993. Enamel microstructure and molar wear in the Greater Galago, Otolemur crassicaudatus (Mammalia, Primates). American Journal of Physical Anthropology, 92:217–233.Google Scholar
Maas, M. C. In press. Enamel microstructure in Notoungulata (Mammalia). In Kay, R. F., Madden, R. H., Flynn, J. J., and Cifelli, R. L. (eds.) Paleobiology of an Extinct Neotropical Fauna: The Miocene Fauna from Colombia. Smithsonian Institution Press, Washington D.C. Google Scholar
Martin, L. B., Boyde, A., and Grine, F. E. 1988. Enamel structure in primates: a review of scanning electron microscope studies. Scanning Microscopy, 2:1503–1526.Google Scholar
McKenna, M. C. 1975. Toward a phylogenetic classification of the Mammalia, p. 21–46. In Luckett, P. W. and Szalay, F. S. (eds.), Phylogeny of the Primates: A Multidisciplinary Approach. Plenum Press, New York.Google Scholar
Milinkovitch, M. C., Orti, G., and Meyer, A. 1993. Revised phylogeny of whales suggested by mitochondrial ribosomal DNA sequences. Nature, 361:346–348.Google Scholar
Myrick, A. C. Jr. 1980. Examination of layered tissues of odontocetes for age determination using polarized light microscopy. Report of the International Whaling Commission, Special Issue 3:105–112.Google Scholar
Novacek, M. J. 1986. The skull of leptictid insectivorans and the higher-level classification of eutherian mammals. Bulletin of the American Museum of Natural History, 183:1–112.Google Scholar
Novacek, M. J. 1992. Mammalian phylogeny: shaking the tree. Nature, 356:121–126.CrossRefGoogle ScholarPubMed
Pfretzschner, H. U. 1993. Enamel microstructure in the phylogeny of the Equidae. Journal of Vertebrate Paleontology, 13:342–349.CrossRefGoogle Scholar
Pierce, K. V. and Kajimura, H. 1980. Acid etching and highlighting for defining growth layers in cetacean teeth. Report of the International Whaling Commission, Special Issue 3:99–103.Google Scholar
Prothero, D. R. 1993. Ungulate phylogeny: molecular vs. morphological evidence, p. 173–181. In Szalay, F. S., Novacek, M. J., and McKenna, M. C. (eds.), Mammal Phylogeny: Placentals. Springer-Verlag, New York.Google Scholar
Prothero, D. R., Manning, E. M., and Fischer, M. 1988. The phylogeny of the ungulates, p. 201–234. In Benton, M. J. (ed.), The Systematics Association Special Volume No. 35B, The Phylogeny and Classification of the Tetrapods. Volume 2. Mammals. Clarendon Press, Oxford.Google Scholar
Sahni, A. 1981a. Dental and skeletal micro- and ultrastructure of Indian Tertiary vertebrates. Proceedings of the IX Indian Colloquium on Micropaleontology and Stratigraphy, 109–122.Google Scholar
Sahni, A. 1981b. Enamel ultrastructure of fossil Mammalia: Eocene Archaeoceti from Kutch. Journal of the Paleontological Society of India, 25:33–37.Google Scholar
Sahni, A. 1987. Evolutionary aspects of reptilian and mammalian enamel structure. Scanning Microscopy, 1:1903–1912.Google Scholar
Sahni, A., and Mishra, V. P. 1975. Lower Tertiary vertebrates from western India. Monograph of the Palaeontological Society of India, 3:1–48.Google Scholar
Sarich, V. M. 1993. Mammalian systematics: twenty-five years among their albumins and transferrins, p. 103–114. In Szalay, F. S., Novacek, M. J., and McKenna, M. C. (eds.), Mammal Phylogeny: Placentals. Springer-Verlag, New York.CrossRefGoogle Scholar
Shobusawa, M. 1952. Vergleichende Untersuchungen über die Form der Schmelzprismen der Säugetiere. Okajimas Folia Anatomica Japonica 24:371–392.Google Scholar
Slijper, E. J. 1962. Whales. Second Edition. Cornell University Press, Ithaca, New York.Google Scholar
Szalay, F. S. 1969. Origin and evolution of function of the mesonychid condylarth feeding mechanism. Evolution, 23:703–720.Google Scholar
Thewissen, J. G. M. 1993. Eocene marine mammals from the Himalayan foothills. Research and Exploration, National Geographic Society, 9:125–127.Google Scholar
Thewissen, J. G. M., and Domning, D. P. 1992. The role of phenacodontids in the origin of the modern orders of ungulate mammals. Journal of Vertebrate Paleontology, 12:494–504.Google Scholar
Thewissen, J. G. M., and Hussain, S. T. 1993. Origin of underwater hearing in whales. Nature, 361:444–445.Google Scholar
Thewissen, J. G. M., Gingerich, P. D., and Russell, D. E. 1987. Artiodactyla and Perissodactyla (Mammalia) from the early-middle Eocene Kuldana Formation of Kohat (Pakistan). Contributions from the Museum of Paleontology, The University of Michigan, 27:247–274.Google Scholar
Tomes, C. S. 1906. On the minute structure of the teeth of creodonts, with especial reference to their suggested resemblance to marsupials. Proceedings of the Zoological Society of London, i:45–58.Google Scholar
Van Valen, L. 1966. Deltatheridia, a new order of mammals. Bulletin of the American Museum of Natural History, 132:1–126.Google Scholar
Werth, A. J., and Stern, D. N. 1992. Functional influences in the evolution and devolution of odontocete enamel. Journal of Vertebrate Paleontology, 12:59A (Abstract).Google Scholar
West, R. M. 1980. Middle Eocene large mammal assemblage with Tethyan affinities, Gandas Kas region, Pakistan. Journal of Paleontology, 54:508–533.Google Scholar
West, R. M., and Lukacs, J. R. 1979. Geology and vertebrate-fossil localities, Tertiary continental rocks, Kala Chitta Hills, Attock District, Pakistan. Contributions in Biology and Geology, Milwaukee Public Museum, 26:1–20.Google Scholar
Wible, J. R. 1987. The eutherian stapedial artery: character analysis and implications for superordinal relationships. Zoological Journal of the Linnean Society, 91:107–135.Google Scholar