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The Serrated Teeth of Tyrannosaurid Dinosaurs, and Biting Structures in Other Animals

Published online by Cambridge University Press:  08 April 2016

William L. Abler
William L. Abler*
Affiliation:
4234 N. Hazel St., Chicago, Illinois 60613
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Abstract

The function of serrated teeth is analyzed by experimental comparison with the action of artificially made steel blades. Serrated blades cut compliant materials with a grip-and-rip mechanism, whereas smooth, sharp blades cut by concentrating a large downward force on a tiny area.

Tyrannosaurid teeth from the Cretaceous Judith River Formation bear rows of serrations that have thick, rounded enamel caps, gripping slots between neighboring serrations, thick enamel bodies inside the teeth underneath the gripping slots, and a root beneath each serration. In contrast, the carnivorous dinosaur Troodon has teeth with exposed pointed serrations, thin enamel, and possibly serration roots.

Serrations on the teeth of Troodon and the fossil shark Carcharodon, cut compliant materials in the same way as a serrated hacksaw blade. In contrast, the cutting action of tyrannosaurid teeth most closely resembles that of a dull smooth blade. The spaces between the serrations act as minute frictional vises that grip and hold meat fibers; chambers between neighboring serrations receive and retain small fragments of meat, and inevitably would have acted as havens where bacteria could be stored. These spaces may therefore have led to infections in wounds, analogous to those inflicted by the living Komodo dragon or ora. By analogy, the hunting and feeding behavior of tyrannosaurs may have resembled that of the ora.

Serrations and slots are widely distributed among cutting devices in the natural world, and many of these deserve further study. For example, the carnassial teeth of mammalian carnivores cut by a combination of static force at the cutting edge, a crushing or scissoring action at the advancing junction between upper and lower teeth, and by lateral gripping and compression in a slot, like that seen on a much smaller scale in tyrannosaurid serrations. Mammalian teeth operate well only when deployed with sophisticated control over jaw movement, however, and the fine neural control necessary to operate them may have formed the basis for the later development of intelligence in mammals.

Previously, being interested in mammals was largely a matter of being interested in teeth, whereas being interested in reptiles was largely a matter of being interested in everything but teeth. I suggest that the teeth of at least some reptiles are as rich in information as the teeth of any mammals.

Type
Research Article
Information
Paleobiology , Volume 18 , Issue 2 , March 1992 , pp. 161 - 183
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Argast, S., Farlow, J. O., Gabet, R. M., and Brinkman, D. L.. 1987. Transport-induced abrasion of fossil reptilian teeth: implications for the existence of Tertiary dinosaurs in the Hell Creek Formation, Montana. Geology 15: 927–930.Google Scholar
Auffenberg, W. 1981. The behavioral ecology of the Komodo Monitor. University of Florida Press, Gainesville, Fla.Google Scholar
Berkovitz, B.K.B., and Shellis, R. P.. 1978. A longitudinal study of tooth succession in piranhas (Pisces: Characidae), with an analysis of the tooth replacement cycle. Journal of Zoology, London 184: 545–561.CrossRefGoogle Scholar
Blair, L., and Blair, L.. 1987/1988. Dance of the warriors. [Film] Blair Brothers Productions, WGBH Education Foundation, and WGBH, Boston.Google Scholar
Brinkman, D., and Eberth, D. A.. 1983. The interrelationships of pelycosaurs. Breviora. Museum of Comparative Zoology. Cambridge, Mass. 473: 1–35.Google Scholar
Buckland, W. 1824. Notice on the Megalosaurus or great fossil lizard of Stonesfield. Transactions of the Geological Society of London. 2nd series. I (Part 2):390–396.Google Scholar
Buckland, W. 1858. Geology and mineralogy considered with reference to natural theology. Routledge, London.Google Scholar
Cuvier, G. 1825. Récherches sur les Ossemens Fossiles, vol. 5. 3rd ed.Dufour et d'Ocagne, Paris.Google Scholar
De Saussure, H.L.F. 1853-1858. Etudes sur la famille des Vespides 2. Masson, Paris.Google Scholar
Diamond, J. M. 1986. How great white sharks, sabre-toothed cats and soldiers kill. Nature (London) 322: 773–774.CrossRefGoogle Scholar
Duncan, C. D. 1939. A contribution to the biology of North American vespine wasps. Stanford University Press, Stanford, Calif.Google Scholar
Eberth, D. A. 1985. The skull of Sphenacodon ferocior and comparisons with other sphenacodontines (Reptilia: Pelycosauria). Circular 190. New Mexico Bureau of Mines and Mineral Resources, Socorro, N.M.Google Scholar
Farlow, J. O., Brinkman, D. L., Abler, W. L., and Currie, P. J.. 1991. Size, shape, and serration density of theropod dinosaur lateral teeth. Modern Geology 16: 161–198.Google Scholar
Flower, W. H. 1885. An introduction to the osteology of the Mammalia, 3rd ed.Macmillan, London.CrossRefGoogle Scholar
Flower, W. H., and Lydekker, R.. 1891. An introduction to the study of mammals living and extinct. A. and C. Black, London.Google Scholar
Fowler, H. W. 1911. A description of the fossil fish remains of the Cretaceous, Eocene and Miocene formations of New Jersey. Bulletin of the New Jersey Geological Survey 4.Google Scholar
Frazzetta, T. H. 1988. The mechanics of cutting and the form of shark teeth (Chondrichthyes, Elasmobranchii). Zoomorphology 108: 93–107.CrossRefGoogle Scholar
Johnson, H., and Storer, J. E.. 1974. A guide to Alberta vertebrate fossils from the age of dinosaurs. Provincial Museum of Alberta, Edmonton, Alberta.Google Scholar
Jordan, D. S. 1908. Fishes. Holt, New York.Google Scholar
Lambe, L. W. 1917. The Cretaceous theropodous dinosaur Gorgosaurus. Geological Survey, Canada Department of Mines. No. 83, Geological Series. Memoir 100.Google Scholar
Langston, W. 1956. The Sebecosuchia: cosmopolitan crocodilians? American Journal of Science 254: 605–614.Google Scholar
Martin, L. D. 1980. Functional morphology and evolution of cats. Transactions of the Nebraska Academy of Sciences 8: 141–154.Google Scholar
Owen, R. 1860. Palaeontology or a systematic summary of extinct animals and their geologic relations. A. and C. Black, Edinburgh, Scotland.Google Scholar
Peterson, A. 1948. Larvae of insects. Part I. Alvah Peterson, Columbus, Ohio.Google Scholar
Peterson, A. 1951. Larvae of insects. Part II. Alvah Peterson, Columbus, Ohio.Google Scholar
Reisz, R. R. 1986. Handbuch der Palaoherpetologie. Encyclopedia of Paleoherpetology. Teil 17A/Part 17A. Pelycosauria. G. Fischer, Stuttgart.Google Scholar
Roberts, T. R. 1967. Tooth formation and replacment in characoid fishes. Stanford Ichthyological Bulletin 8: 231–247.Google Scholar
Romer, A. S., and Price, L. W.. 1940. Review of the Pelycosauria. Geological Society of America. Special papers. No. 28.Google Scholar
Snodgrass, R. E. 1931. Evolution of the insect head and the organs of feeding. Pp. 443–489in Annual Report of the Board of Regents of the Smithsonian Institution. U.S. Government Printing Office, Washington.Google Scholar
Snodgrass, R. E. 1935. Principles of insect morphology. McGraw-Hill, New York.Google Scholar
Wallis, J. B. 1961. The Cicindelidae of Canada. University of Toronto Press, Toronto, Ontario.Google Scholar
Wolach, A. H. 1984. Nonparametric statistics for Timex-Sinclair 2X81, 1000, and 1500 microcomputers. K.D.V.H.E. Publishers, Chicago, Ill.Google Scholar
Young, J. Z. 1962. The life of vertebrates. Oxford University Press, Oxford.Google Scholar