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Internal reconstruction of elephantid molars: applications for functional anatomy and systematics

Published online by Cambridge University Press:  08 February 2016

David J. Froehlich  and
Jon E. Kalb
David J. Froehlich
Affiliation:
Department of Geological Sciences and Vertebrate Paleontology Laboratory, J. J. Pickle Research Campus, University of Texas, Austin, Texas 78712
Jon E. Kalb
Affiliation:
Vertebrate Paleontology Laboratory, J. J. Pickle Research Campus, University of Texas, Austin, Texas 78712
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Abstract

The unique manner in which molars from members of the family Elephantidae erupt in the jaw and wear obliquely and sequentially has profound effects upon dental function and phylogenetic change within the group. Three-dimensional modeling using a “molar matrix” of elephantid dentition, and application of such models to systematic and functional studies, allows a more refined description of dental morphology. A method of examining variation within elephantid teeth is presented based on successive staging of worn molars. Results indicate that individual plates exhibit increasingly derived features with wear (relative to the systematic analysis used here), while successively worn plates exhibit successively more plesiomorphic features apically and posteriorly. Further, results indicate that the patterns developed by wear on the surface of elephantid molars are conserved throughout life despite their unique successive replacement pattern. The cheek teeth in a molar series act as a single, continuous masticating unit, here termed a “cheek tooth battery.” Overall, the tools developed here, wear staging and molar matrices, allow for a more refined understanding of morphological variation within and between elephantids, with application to more conservative elephantoid taxa.

Type
Articles
Information
Paleobiology , Volume 21 , Issue 3 , Summer 1995 , pp. 379 - 392
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Aguirre, E. 1968. Revision sistematica de los Elephantidae por su morfologia y morfometria dentaria. Estudios Geologicos (Madrid) 34:107–116.Google Scholar
Coppens, Y., Maglio, V. J., Madden, C. T., and Beden, M. 1978. Proboscidea. Pp. 336–367in Maglio, V. J. and Cooke, H. B. S., eds. Evolution of African mammals. Harvard University Press, Cambridge.CrossRefGoogle Scholar
Gaziry, A. W. 1987. Remains of Proboscidea from the Pliocene of Sahabi, Libya. Pp. 183–203in Boaz, N. T., El-Arnauti, A., Gaziry, A. W., de Heinzelin, J., and Boaz, D. D., eds. Neogene paleontology and geology of Sahabi. Alan R. Liss, New York.Google Scholar
Kalb, J. E. 1993. Refined stratigraphy of the hominid-bearing Awash Group, Middle Awash Valley, Afar Depression, Ethiopia. Newsletters on Stratigraphy 29:21–62.CrossRefGoogle Scholar
Kalb, J. E., and Froehlich, D. J.In press. Origins of late Neogene elephantoids: new evidence from the Middle Awash Valley, Afar, Ethiopia. Geobios.Google Scholar
Kalb, J. E., and Mebrate, A. 1993. Fossil elephantoids from the hominid-bearing Awash Group, Middle Awash Valley, Afar Depression, Ethiopia. American Philosophical Society Transactions 83:1–114.CrossRefGoogle Scholar
Kalb, J. E., Froehlich, D. J., and Bell, G. L. 1995. Phylogeny of African and Eurasian Elephantoidea of the late Neogene. In pressin Shoshani, J. and Tassy, P., eds. The Proboscidea: trends in evolution and paleoecology. Oxford University Press.Google Scholar
Laws, R. M. 1966. Age criteria for the African elephant, Loxodonta a. africana. East African Wildlife Journal 4:1–37.CrossRefGoogle Scholar
Maglio, V. J. 1972. Evolution of mastication in the Elephantidae. Evolution 26(4):638–658.CrossRefGoogle ScholarPubMed
Maglio, V. J. 1973. Origin and evolution of the Elephantidae. American Philosophical Society Transactions 63:1–149.CrossRefGoogle Scholar
Maglio, V. J., and Ricca, A. B. 1978. Dental and skeletal morphology of the earliest elephants. Verhandelingen der Koninklijke Nederlandse Akademie Van Wetenschappen, Natuurkunde 29:1–50.Google Scholar
Osborn, H. F. 1942. Proboscidea, Vol. 2. American Museum Press, New York.Google Scholar
Petrocchi, C. 1943. Il giaceimento fossilifero di Sahabi. Parte 2, Paleontologia. Colliezione Scientifica e Documentaria dell'Africa Italian, Ministers dell'Africa Itialiana 12:69–167.Google Scholar
Potts, R., and Behrensmeyer, A. K. 1992. Late Cenozoic terrestrial ecosystems. Pp. 419–520in Behrensmeyer, A. K., Damuth, J. D., DiMichele, W. A., Potts, R., Sues, H.-D., and Wing, S. L., eds. Terrestrial ecosystems through time: evolutionary paleoecology of terrestrial plants and animals. University of Chicago Press.Google Scholar
Roth, V. L. 1989. Fabricational noise in elephant dentitions. Paleobiology 15:165–179.CrossRefGoogle Scholar
Saegusa, H. 1995. Stegodontidae: evolutionary relations. In pressin Shoshani, J. and Tassy, P., eds. The Proboscidea: trends in evolution and paleoecology. Oxford University Press.Google Scholar
Sikes, S. K. 1971. The natural history of the African elephant. Wiedenfeld and Nicolsen, London.Google Scholar
Tassy, P. 1983. Les Elephantoidea miocènes du plateau du Potwar, Groupe de Siwalik, Pakistan. Annuales Paleontologie 69:99–136, 235-298, 317-354.Google Scholar
Tassy, P. 1988. The classification of Proboscidea: how many cladistic classifications? Cladistics 4:43–57.CrossRefGoogle ScholarPubMed
Tassy, P., and Shoshani, J. 1988. The Tethytheria: elephants and their relatives. Pp. 283–315in Benton, M. J., ed. The phylogeny and classification of the tetrapods, Vol. 2. Special Volume 35B. Systematics Association, Oxford.Google Scholar