Skip to main content

Advertisement

Log in

Evolution of the power stroke in early Equoidea (Perissodactyla, Mammalia)

  • Original Paper
  • Published:
Palaeobiodiversity and Palaeoenvironments Aims and scope Submit manuscript

Abstract

During the early evolution of Equoidea, two families co-existed, Equidae and Palaeotheriidae. Both groups show a similar ancestral molar morphology and evolved from bunodont to lophodont or selenolophodont (lophodont with crescent-shaped cutting edge in some form) respectively, with a clearly pronounced ectoloph. Fossils of the here studied brachydont equids and palaeotheriids are known from the early Eocene to the middle Miocene in North America and Eurasia. Due to the rich fossil record, dental evolution and related functional shifts can be investigated in detail in each family. In this study, we focused on changes in the different masticatory paths, identified different functions within the power stroke and evaluated the efficiency of the different modes in mastication to correlate tooth morphology to the potential palaeodiets. The analysis is based on three-dimensional (3D) polygonal surface scans, allowing the detailed investigation of morphological features. The results show that primitive equoids possess well-developed cutting and shearing structures, despite being generally referred to as simply bunodont. These structures enable the primitive forms to break down structural plant parts more efficiently than for example Phenacodus (‘condylarth’ outgroup), showing simple rounded cusps, and therefore representing a more primitive type of bunodont dentition. It is general consensus that the diet of the more derived early equoids shifts to a higher percentage of tough plant parts and they adopt different strategies to efficiently comminute those parts. Equids emphasise cutting and shearing both buccally and lingually, trending towards a one-phase power stroke, a pattern resembling that of modern hypsodont Equidae. Our results suggest that the derived brachydont equids specialised to consume leaves rather than grasses. In comparison, derived palaeotheriids mainly emphasise shearing and cutting function buccally and a distinct grinding function in a two-phase power stroke. The combination of different functions suggest a broader diet different from only leaves, likely including twigs or hard fruits.

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.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

References

  • Academy of Prosthodontics. (2005). Glossary-of-prosthodontic-terms (8th edition). Journal of Prosthetic Dentistry, 94(1), 10–92.

    Google Scholar 

  • Ahbusch-Siewert, S. (1983). Gebissmorphologische Untersuchungen an eurasiatischen Anchitherien (Equidae, Mammalia) unter besonderer Berücksichtigung der Fundstelle Sandelzhausen. Courier Forschungsinstitut Senckenberg, 62, 1–36.

    Google Scholar 

  • Anders, U. (2011). Funktionsmorphologische Veränderungen und Funktionalitätserhaltung in bunodonten, selenodonten und secodonten Gebissen. Dissertation thesis, Rheinische Friedrich-Wilhelm-Universität Bonn, urn:nbn:de:hbz:5N-27360.

  • Anders, U., Koenigswald, W. von, Ruf, I., & Smith, H. B. (2010). Generalized individual dental age stages for fossil and extant placental mammals. Paläontologische Zeitschrift, 85, 321–339.

  • Bae, D. H., Welch, J. G., & Smith, A. M. (1981). Efficiency of mastication in relation to hay intake by cattle. Journal of Animal Science, 52(6), 1371–1375.

    Google Scholar 

  • Bai, B. (2017). Eocene Pachynolophinae (Perissodactyla, Palaeotheriidae) from China, and their palaeobiogeographical implications. Palaeontology, 60(6), 837–852.

    Google Scholar 

  • Bai, B., Wang, Y., Meng, J., Li, Q., & Jin, X. (2014). New early Eocene basal tapiromorph from southern China and its phylogenetic implications. PLoS One, 9(10), e110806.

    Google Scholar 

  • Batzli, G. O., & Hume, I. D. (1994). Foraging and digestion in herbivores. In D. J. Chivers, & P. Langer (Eds.) The digestive system in mammals: Food, form and function (pp. 313–314). Cambridge: Cambridge University Press.

  • Boyer, D. (2008). Relief index of second mandibular molars is a correlate of diet among prosimian primates and other euarchontan mammals. Journal of Human Evolution, 55, 1118–1137.

    Google Scholar 

  • Brockhaus. (1982). dtv Brockhaus Lexikon. Mannheim: F.A. Brockhaus.

    Google Scholar 

  • Butler, M. (1951a). The milk-molars of Perissodactyla, with remarks on molar occlusion. Proceeding of the Zoological Journal of London, 121, 777–817.

    Google Scholar 

  • Butler, P. M. (1951b). Molarization of the premolars in the Perissodactyla. Proceeding of the Zoological Journal of London, 121, 819–843.

    Google Scholar 

  • Butler, P. M. (1980). Functional aspects of the evolution of rodent molars. Palaeovertebrata (Mémoire Jubilaire René Lavocat), 249–262.

  • Butler, P. M. (1985). Homologies of molar cusps and crests, and their bearing on assessments of rodent phylogeny. In W. P. Luckett & J. L. Hartenberger (Eds.), Evolutionary relationships among rodents (pp. 381–401). New York and London: Plenum Press.

    Google Scholar 

  • Clauss, M., Nunn, C., Fritz, J., & Hummel, J. (2009). Evidence for a tradeoff between retention time and chewing efficiency in large mammalian herbivores. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 154, 376–382.

    Google Scholar 

  • Collinson, M. E., & Hooker, J. J. (1991). Fossil evidence of interactions between plants and plant-eating animals. Philosophical Transactions of the Royal Society B, 333, 197–208.

    Google Scholar 

  • Costa, R. L. J., & Greaves, W. S. (1981). Experimentally produced tooth wear facets and the direction of jaw motion. Journal of Paleontology, 55(3), 635–638.

    Google Scholar 

  • Crompton, A. W. (1971). The origin of the tribosphenic molar. In D. M. Kermack & K. A. Kermack  (Eds.) Early Mammals. Zoological Journal of the Linnean Society, 50(Suppl. 1), 65–87.

  • Crompton, A. W., & Hiiemae, K. (1969). How mammalian teeth work. Discovery, 5(1), 23–34.

    Google Scholar 

  • Crompton, A. W., & Hiiemae, K. (1970). Molar occlusion and mandibular movements during occlusion in the American opossum, Didelphis marsupialis L. Zoological Journal of the Linnean Society, 49, 21–47.

    Google Scholar 

  • Crompton, A. W., & Kielan-Jaworowska, Z. (1978). Molar structure and occlusion in cretaceous therian mammals. In P. M. Butler & K. A. Joysey (Eds.), Development, function and evolution of teeth (pp. 249–287). London: Academic Press.

    Google Scholar 

  • Damuth, J., & Janis, C. M. (2014). A comparison of observed molar wear rates in extant herbivorous mammals. Annales Zoologici Fennici, 51, 188–200.

    Google Scholar 

  • Danilo, L., Remy, J. A., Vianey-Liaud, M., Marandat, B., Sudre, J., & Lihoreau, F. (2013). A new Eocene locality in southern France sheds light on the basal radiation of Palaeotheriidae (Mammalia, Perissodactyla, Equoidea). Journal of Vertebrate Paleontology, 33(1), 195–215.

    Google Scholar 

  • Drucker, P. F. (2007). The effective executive. Oxford: Elsevier.

    Google Scholar 

  • Engels, S. (2007). Funktionelle Morphologie des Schädels und der Bezahnung der Ursidae. Diploma thesis. Johann Wolfgang Goethe-Universität Frankfurt am Main: http://hopsea.mnhn.fr/pc/thesis/Diploma_Engels_2007.pdf

  • Engels, S. (2011). Funktionelle und morphologische Transformationen der Molaren bei frühen Hippomorpha im Hinblick auf den Mastikationsprozess. Dissertation thesis, Rheinische Friedrich-Wilhelm-Universität Bonn, urn:nbn:de:hbz:5N-27227.

  • Evans, A. R. (2005). Connecting morphology, function and tooth wear in microchiropterans. Biological Journal of the Linnean Society, 85, 81–96.

    Google Scholar 

  • Evans, A. R., & Fortelius, M. (2008). Three-dimensional reconstruction of tooth relationships during carnivoran chewing. Palaeontologica Electronica, 11(2), 1–11.

    Google Scholar 

  • Evans, A. R., & Janis, C. M. (2014). The evolution of high dental complexity in the horse lineage. Annales Zoologici Fennici, 51(1–2), 73–79.

    Google Scholar 

  • Evans, A. R., & Sanson, G. D. (2003). The tooth of perfection: Functional and spatial constraints on mammalian tooth shape. Biological Journal of the Linnean Society, 78, 173–191.

    Google Scholar 

  • Evans, A. R., & Sanson, G. D. (2006). Spatial and functional modeling of carnivore and insectivore molariform teeth. Journal of Morphology, 267, 649–662.

    Google Scholar 

  • Evans, A. R., Wilson, G. P., Fortelius, M., & Jernvall, J. (2007). High-level similarity of dentitions in carnivorans and rodents. Nature, 445, 78–81.

    Google Scholar 

  • Forsten, A. (1991). Size trends in holarctic anchitherines (Mammalia, Equidae). Journal of Paleontology, 65(1), 147–159.

    Google Scholar 

  • Fortelius, M. (1981). Functional aspects of occlusal cheek-tooth morphology in hypsodont, non-ruminant ungulates (pp. 153–162). Barcelona: International Symposium on Concepts and Methods in Paleontology.

  • Fortelius, M. (1982). Ecological aspects of dental functional morphology in the Plio-Pleistocene rhinoceroses of Europe. In B. Kurtén (Ed.), Teeth: Form, function, and evolution (pp. 163–181). New York: Columbia University Press.

    Google Scholar 

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

    Google Scholar 

  • Fortelius, M., & Solounias, N. (2000). Functional characterization of ungulate molars using the abrasion-attrition wear gradient: a new method for reconstructing paleodiets. American Museum Novitates, 3301, 1–36.

    Google Scholar 

  • Fortelius, M., Eronen, J., Liu, L., Pushkina, D., Tesakov, A., Vislobokova, I., & Zhang, Z. (2003). Continental-scale hypsodonty patterns, climatic paleobiogeography and dispersal of Eurasian Neogene large mammal herbivores. In J. W. F. Reumer & W. Wessels (Eds.) Distribution and migration of tertiary mammals in Eurasia - A volume in honor of Hans de Bruijn (pp. 1–12). Deinsea 10. Natuurmuseum Rotterdam.

  • Franzen, J. L. (1984). Die Stammesgeschichte der Pferde in ihrer wissenschaftshistorischen Entwicklung. Natur und Museum, 114(6), 149–162.

    Google Scholar 

  • Franzen, J. L. (1985). Exceptional preservation of Eocene vertebrates in the lake deposit of Grube Messel (West Germany). Philosophical Transactions of the Royal Society B, 311, 181–186.

    Google Scholar 

  • Franzen, J. L. (1989). Origin and systematic position of the Palaeotheriidae. In D. R. Prothero & R. M. Schoch (Eds.), The Evolution of Perissodactyls (pp. 102–107). Oxford: Oxford University Press.

    Google Scholar 

  • Franzen, J. L. (2006). Eurohippus n.g., a new genus of horses from the Middle to Late Eocene of Europe. Senckenbergiana lethaea, 86(1), 97–102.

    Google Scholar 

  • Franzen, J. L. (2007). Eozäne Equoidea (Mammalia, Perissodactyla) aus der Grube Messel bei Darmstadt (Deutschland); Funde der Jahre 1969–2000. Schweizerische Paläontologische Abhandlungen, 127, 1–245.

    Google Scholar 

  • Franzen, J. L., & Habersetzer, J. (2017). Complete skeleton of Eurohippus messelensis (Mammalia, Perissodactyla, Equoidea) from the early middle Eocene of Grube Messel (Germany). Palaeobiodiversity and Palaeoenvironments, 97(4), 807-832.

  • Fritz, J., Hummel, J., Kienzle, E., Arnold, C., Nunn, C., & Clauss, M. (2009). Comparative chewing efficiency in mammalian herbivores. Oikos, 118, 1623–1632.

    Google Scholar 

  • Froehlich, D. J. (1999). The phylogenetic systematics of the basal perissodactyls. Journal of Vertebrate Paleontology, 19, 140–159.

    Google Scholar 

  • Froehlich, D. J. (2002). Quo vadis eohippus? The systematics and taxonomy of the early Eocene equids (Perissodactyla). Zoological Journal of the Linnean Society, 134(2), 141–256.

    Google Scholar 

  • Gipps, J. M., & Sanson, G. D. (1984). Mastication and digestion in Pseudocheirus. In A. P. Smith & I. D. Hume (Eds.), Possums and gliders (pp. 237–246). Sydney: Australian Mammal Society.

    Google Scholar 

  • Gouraud, H. (1971). Continuous shading of curved surfaces. IEEE Transactions on Computers, C-20(6), 623–629.

    Google Scholar 

  • Greaves, W. S. (1973). The inference of jaw motion from tooth wear facets. Journal of Paleontology, 47(5), 1000–1001.

    Google Scholar 

  • Greaves, W. S. (1974). Functional implications of mammalian jaw point position. Forma et Functio, 7, 363–376.

    Google Scholar 

  • Grippo, J. O., Simring, M., & Schreiner, S. (2004). Attrition, abrasion, corrosion and abfraction revisited. A new perspective on tooth surface lesions. Journal of the American Dental Association, 135, 1109–1118.

    Google Scholar 

  • Helkimo, E., Carlsson, G. E., & Melkimo, M. (1978). Chewing efficiency and state of dentition. Acta Odontolgica Scandinavica, 36(1), 33–41.

    Google Scholar 

  • Herring, S. W., & Scapino, R. P. (1973). Physiology of feeding in miniature pigs. Journal of Morphology, 141, 427–460.

    Google Scholar 

  • Hielscher, R. C., Schultz, J. A. & Martin, T. (2015). Wear pattern of the molar dentition of an extant an Oligocene bat assemblage with implications on functionality. Palaeobiodiversity and Palaeoenvironments 95: 597–611.

  • Hiiemae, K. (1976). Masticatory movements in primitive mammals. In B. Anderson & B. Matthews (Eds.), Mastication (pp. 105–118). Bristol: Wright.

    Google Scholar 

  • Hiiemae, K. M., & Kay, R. F. (1973). Evolutionary trends in the dynamics of primate mastication. Symposium of the 4th International Congress of Primatology, 28–64.

  • Holbrook, L. T. (1999). The phylogeny and classification of tapiromorph perissodactyls (Mammalia). Cladistics, 15(3), 331–350.

    Google Scholar 

  • Holbrook, L. T., & Lapergola, J. (2011). A new genus of perissodactyl (Mammalia) from the Bridgerian of Wyoming, with comments on basal perissodactyl phylogeny. Journal of Vertebrate Paleontology, 31(4), 895–901.

    Google Scholar 

  • Hunter, J., & Fortelius, M. (1994). Comparative dental occlusal morphology, facet development, and microwear in two sympatric species of Listriodon (Mammalia: Suidae) from the Middle Miocene of western Anatolia (Turkey). Journal of Vertebrate Paleontology, 14(1), 105–126.

    Google Scholar 

  • Hylander, W. L., & Crompton, A. W. (1986). Jaw movements and patterns of mandibular bone strain during mastication in the monkey Macaca fascicularis. Archives of Oral Biology, 31(12), 841–848.

    Google Scholar 

  • Hylander, W. L., Johnson, K. R., & Crompton, A. W. (1987). Loading patterns and jaw movements during mastication in Macaca fascicularis: A bone-strain, electromyographic, and cineradiographic analysis. American Journal of Physical Anthropology, 72, 287–314.

    Google Scholar 

  • Janis, C. M. (1979). Mastication in the hyrax and its relevance to ungulate dental evolution. Palaeobiology, 5(1), 50–59.

    Google Scholar 

  • Janis, C. M. (1990). The correlation between diet and dental wear in herbivorous mammals, and its relationship to the determination of diets of extinct species. In A. J. Boucot (Ed.), Evolutionary paleobiology of behavior and coevolution (pp. 241–260). Amsterdam: Elsevier.

    Google Scholar 

  • Janis, C. M. (2007). The horse series. In B. Regal (Ed.), Icons of evolution (pp. 257–280). West-port: Greenwood Press.

    Google Scholar 

  • Janis, C. M. (2008). An evolutionary history of browsing and grazing ungulates. In I. J. Gordon & H. H. T. Prins (Eds.), The ecology of browsing and grazing (pp. 21–45). Heidelberg: Springer-Verlag.

    Google Scholar 

  • Jernvall, J. (1995). Mammalian molar cusp patterns: developmental mechanisms of diversity. Acta Zoologica Fennica, 198, 1–61.

    Google Scholar 

  • Jernvall, J., Hunter, J. P., & Fortelius, M. (1996). Molar tooth diversity, disparity, and ecology in Cenozoic ungulate radiations. Science, 274, 1489–1492.

    Google Scholar 

  • Jones, K. E., & Holbrook, L. T. (2016). The evolution of lateral accessory articulations in the lumbar region of perissodactyls. Journal of Vertebrate Paleontology, 36(6), e1224892.

    Google Scholar 

  • Joomun, S. C., Hooker, J. J., & Collinson, M. E. (2008). Dental wear variation and implications for diet: an example from Eocene perissodactyls (Mammalia). Palaeogeography, Palaeoclimatology, Palaeoecology, 263, 92–106.

    Google Scholar 

  • Kaiser, T. M. (2009). Anchitherium aurelianense (Equidae, Mammalia): a brachydont "dirty browser" in the community of herbivorous large mammals from Sandelzhausen (Miocene, Germany). Paläontologische Zeitschrift, 83, 131–140.

    Google Scholar 

  • Karme, A., Rannikko, J., Kallonen, A., Clauss, M., & Fortelius, M. (2016). Mechanical modelling of tooth wear. Journal of the Royal Society Interface, 13(120), 20160399.

    Google Scholar 

  • Kay, R. F. (1975). The functional adaptions of primate molar teeth. American Journal of Physical Anthropology, 43(2), 195–216.

    Google Scholar 

  • Kay, R. F. (1977). The evolution of molar occlusion in the Cercopithecidae and early catarrhines. American Journal of Physical Anthropology, 46, 327–352.

    Google Scholar 

  • Kay, R. F., & Hiiemae, K. M. (1974). Jaw movement and tooth use in recent and fossil primates. American Journal of Physical Anthropology, 40(2), 227–256.

    Google Scholar 

  • King, S. J., Arrigo-Nelson, S. J., Pochron, S. T., Semprebon, G. M., Godfrey, L. R., Wright, P. C., & Jernvall, J. (2005). Dental senescence in a long-lived primate links infant survival to rainfall. Proceedings of the National Academy of Sciences of the United States of America, 102(46), 16579–16583.

    Google Scholar 

  • Koenigswald, W. von, & Schaarschmidt, F. (1983). Ein Urpferd aus Messel, dass Weinbeeren fraß. Natur und Museum, 113(3), 79–84.

    Google Scholar 

  • Koenigswald, W. von, Sander, P. M., Leite, M. B., Mörs, T., & Santel, W. (1994). Functional symmetries in the Schmelzmuster and morphology of rootless rodent molars. Zoological Journal of the Linnean Society, 110, 141–179.

    Google Scholar 

  • Koenigswald, W. von, Anders, U., Engels, S., Schultz, J. A., & Ruf, I. (2010). Tooth morphology in fossil and extant Lagomorpha (Mammalia) reflects different mastication patterns. Journal of Mammalian Evolution, 17(4), 275–299.

    Google Scholar 

  • Koenigswald, W. von, Anders, U., Engels, S., Schultz, J. A., & Kullmer, O. (2012). Jaw movement in fossil mammals: analysis, description and visualization. Paläontologische Zeitschrift, 87, 141–159.

    Google Scholar 

  • Kullmer, O., Benazzi, S., Fiorenza, L., Schulz, D., Bacso, S., & Winzen, O. (2009). Technical note: Occlusal fingerprint analysis: Quantification of tooth wear pattern. American Journal of Physical Anthropology, 139(4), 600–605.

    Google Scholar 

  • Lanyon, J. M., & Sanson, G. D. (1986). Koala (Phasolarctos cinereus) dentition and nutrition. II. Implications of tooth wear in nutrition. Journal of Zoology, 209, 169–181.

    Google Scholar 

  • Lazzari, V., Charles, C., Tafforeau, P., Vianey-Liaud, M., Aguilar, J.-P., Jaeger, J.-J., Michaux, J., & Viriot, L. (2008). Mosaic convergence of rodent dentitions. PLoS One, 3(10), 1–13.

    Google Scholar 

  • Logan, M., & Sanson, G. D. (2002). The effect of tooth wear on the feeding behavior of free-ranging koalas (Phascolarctos cinereus, Goldfuss). Journal of Zoology, 256, 63–69.

    Google Scholar 

  • Lucas, P. W. (1979). The dental-dietary adaptions of mammals. Neues Jahrbuch für Geologie Paläontologie Monatshefte, 8, 486–512.

    Google Scholar 

  • Lucas, P. W. (2004). Dental functional morphology—how teeth work. Cambridge: Cambridge University Press.

    Google Scholar 

  • Lucas, P. W., Omar, R., Al-Fadhalah, K., Almusallam, A. S., Henry, A. G., Michael, S., Thai, L. A., Watzke, J., Strait, D. S., & Atkins, A. G. (2013). Mechanisms and causes of wear in tooth enamel: implications for hominin diets. Journal of the Royal Society Interface, 10(80), 20120923.

    Google Scholar 

  • Lucas, P. W., Casteren, A., Al-Fadhalah, K., Almusallam, A. S., Henry, A. G., Michael, S., Watzke, J., Reed, D. A., Diekwisch, T. G. H., Strait, D. S., & Atkins, A. G. (2014). The role of dust, grit and phytoliths in tooth wear. Annales Zoologici Fennici, 51, 143–152.

    Google Scholar 

  • Luke, D. A., & Lucas, P. W. (1983). The significance of cusps. Journal of Oral Rehabilitation, 10, 197–206.

    Google Scholar 

  • Lumsden, A. G. S., & Osborn, J. W. (1977). The evolution of chewing: a dentist's view of paleontology. Journal Dentistry, 4(4), 269–287.

    Google Scholar 

  • MacFadden, B. J. (1976). Cladistic analysis of primitive equids with notes on other perissodactyls. Systematic Zoology, 25(1), 1–14.

    Google Scholar 

  • MacFadden, B. J. (1986). Fossil horses from “Eohippus” (Hyracotherium) to Equus: scaling, Cope's law, and the evolution of body size. Paleobiology, 12(4), 355–369.

    Google Scholar 

  • MacFadden, B. J. (1988). Fossil horses from “Eohippus” (Hyracotherium) to Equus, 2: rates of dental evolution revisited. Biological Journal of the Linnean Society, 35(1), 37–48.

    Google Scholar 

  • MacFadden, B. J. (1994). Fossil horses: systematics, paleobiology, and evolution of the family Equidae. Cambridge. New York: Cambridge University Press.

    Google Scholar 

  • MacFadden, B. J. (2005). Fossil horses-evidence for evolution. Science, 307(5716), 1728–1730.

    Google Scholar 

  • MacFadden, B. J., & Hulbert Jr., R. C. (1988). Explosive speciation at the base of the adaptive radiation of Miocene grazing horses. Nature, 336, 466–468.

    Google Scholar 

  • Maier, W. (1978). Zur Evolution des Säugetiergebisses - Typologische und konstruktionsmorphologische Erklärungen. Natur und Museum, 108(10), 288–300.

    Google Scholar 

  • Maier, W. (1980). Konstruktionsmorphologische Untersuchungen am Gebiß der rezenten Prosimiae (Primates). Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft, 538, 1–158.

    Google Scholar 

  • McKenna, M., & Bell, S. K. (1997). Classification of mammals above the species level. New York: Columbia University Press.

    Google Scholar 

  • Merceron, G., Ramdarshan, A., Blondel, C., Boisserie, J.-R., Brunetiere, N., Francisco, A., Gautier, D., Milhet, X., Novello, A., & Pret, D. (2016). Untangling the environmental from the dietary: dust does not matter. Proceedings of the Royal Society B, 283(1838), 20161032.

    Google Scholar 

  • Mihlbachler, M. C., Rivals, F., Solounias, N., & Semprebon, G. M. (2011). Dietary change and evolution of horses in North America. Science, 331, 1178–1181.

    Google Scholar 

  • Mills, J. R. E. (1966). The functional occlusion of the teeth of Insectivora. Zoological Journal of the Linnean Society, 47(308), 1–22.

    Google Scholar 

  • Mills, J. R. E. (1967). A comparison of lateral jaw movements in some mammals from wear facets on the teeth. Archives of Oral Biology, 12, 645–661.

    Google Scholar 

  • Owen-Smith, N. (1988). Megaherbivores - The influence of very large body size on ecology. Cambridge: Cambridge University Press.

    Google Scholar 

  • Pérez-Barberia, F. J., & Gordon, I. J. (1998a). The influence of molar occlusal surface area on the voluntary intake, digestion, chewing behavior and diet selection of red deer (Cervus elaphus). Journal of Zoology, 245, 307–316.

    Google Scholar 

  • Pérez-Barberia, F. J., & Gordon, I. J. (1998b). Factors effecting food comminution during chewing in ruminants: a review. Biological Journal of the Linnean Society, 63, 233–256.

    Google Scholar 

  • Piperno, D., & Pearsall, D. H. (1998). The silica bodies of tropical American grasses: Morphology, taxonomy and implications for the grass systematics and fossil phytolith identification. Smithsonian Contributions to Botany, 85, 1–40.

    Google Scholar 

  • Radinsky, L. (1966). The adaptive radiation of the phenacodontid condylarths and the origin of the Perissodactyla. Evolution, 20, 408–417.

    Google Scholar 

  • Reed, D. A., & Ross, C. F. (2010). The influence of food material properties on jaw kinematics in the primate Cebus. Archives of Oral Biology, 55, 946–962.

    Google Scholar 

  • Rensberger, J. M. (1973). An occlusion model for mastication and dental wear in herbivorous mammals. Journal of Paleontology, 47(3), 515–528.

    Google Scholar 

  • Rensberger, J. M. (1986). Early chewing mechanisms in mammalian herbivores. Paleobiology, 12(4), 474–494.

    Google Scholar 

  • Rensberger, J. M., Forsten, A., & Fortelius, M. (1984). Functional evolution of the cheek tooth pattern and chewing direction in Tertiary horses. Paleobiology, 10(4), 439–452.

    Google Scholar 

  • Rose, K. D. (2006). The beginning of the age of mammals. Baltimore: The John Hopkins University Press.

    Google Scholar 

  • Rose, K. D., Holbrook, L. T., Rana, R. S., Kumar, K., Jones, K. E., Ahrens, H. E., Missiaen, P., Sahni, A., & Smith, T. (2014). Early Eocene fossils suggest that the mammalian order Perissodactyla originated in India. Nature Communications, 5, 5570.

    Google Scholar 

  • Rose, K. D., Holbrook, L. T., & Luckett, W. P. (2017). Deciduous premolars of Eocene Equidae and their phylogenetic significance. Historical Biology, 1–30.

  • Sanson, G. (2006). The biomechanics of browsing and grazing. American Journal of Botany, 93(10), 1531–1545.

    Google Scholar 

  • Sanson, G. D., Kerr, S. A., & Gross, K. A. (2007). Do silica phytoliths really wear mammalian teeth? Journal of Archaeological Science, 34, 526–531.

    Google Scholar 

  • Schultz, J. A. (2012). Funktionelle Morphologie und Abnutzungsmuster prätribosphenischer Molaren am Beispiel der Dryolestida (Mammalia, Cladotheria). Dissertation thesis, Rheinische Friedrich-Wilhelm-Universität Bonn, urn:nbn:de:hbz:5N-27873.

  • Schultz, J. A., & Martin, T. (2014). Function of pretribosphenic and tribosphenic mammalian molars inferred from 3D animation. Naturwissenschaften, 101(10), 771–781.

    Google Scholar 

  • Schultz, J. A., Krause, D. W., Koenigswald, W. von, & Dumont, E. R. (2014). Dental function and diet of Vintana Sertichi (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology, 34(Suppl. 1), 182–202.

  • Schulz, E., Calandra, I., & Kaiser, T. M. (2010). Applying tribology to teeth of hoofed mammals. Scanning, 32, 162–182.

    Google Scholar 

  • Semprebon, G. M., Rivals, F., Solounias, N., & Hulbert, R. C. (2016). Paleodietary reconstruction of fossil horses from the Eocene through Pleistocene of North America. Palaeogeography, Palaeoclimatology, Palaeoecology, 442, 110–127.

    Google Scholar 

  • Sheine, W. S., & Kay, R. F. (1982). A model for comparison of masticatory effectiveness in primates. Journal of Morphology, 172, 139–149.

    Google Scholar 

  • Slavicek, G., Soykher, M., Gruber, H., Siegl, P., & Oxtoby, M. (2009). A novel standard food model to analyse the individual parameters of human mastication. International Journal of Stomatology & Occlusion Medicine, 2, 163–174.

    Google Scholar 

  • Solounias, N., & Semprebon, G. M. (2002). Advances in the reconstruction of ungulate ecomorphology with application to early fossil equids. American Museum Novitates, 3366, 1–49.

    Google Scholar 

  • Stirton, R. A. (1941). Development of characters in horse teeth and the dental nomenclature. Journal of Mammalogy, 22(4), 434–446.

    Google Scholar 

  • Strömberg, C. A. E. (2006). Evolution of hypsodonty in equids: testing a hypothesis of adaptation. Paleobiology, 32(2), 236–258.

    Google Scholar 

  • Thenius, E. (1989). Zähne und Gebiss der Säugetiere. Handbuch der Zoologie, Band VIII Mammalia, Teilband 56. Berlin: Walter de Gruyter & Co..

    Google Scholar 

  • Thewissen, J. G. M., & Domning, D. P. (1992). The role of phenacodontids in the origin of the modern orders of ungulate mammals. Journal of Vertebrate Paleontology, 12(4), 494–504.

    Google Scholar 

  • Tütken, T., & Vennemann, T. (2009). Stable isoptope ecology of Miocene large mammals from Sandelzhausen, southern Germany. Paläontologische Zeitschrift, 83, 207–226.

    Google Scholar 

  • Ungar, P. S., Teaford, M. F., Glander, K. E., & Pastor, R. F. (1995). Dust accumulation in the canopy: a potential cause of dental microwear in primates. American Journal of Physical Anthropology, 97, 93–99.

    Google Scholar 

  • Wall, C. E., Vinyard, C. J., Johnson, K. R., Williams, S. H., & Hylander, W. L. (2006). Phase II jaw movements and masseter muscle activity during chewing in Papio anubis. American Journal of Physical Anthropology, 129, 215–224.

    Google Scholar 

  • Wilde, V., & Hellmund, M. (2010). First record of gut contents from a middle Eocene equid from the Geiseltal near Halle (Saale), Sachsen-Anhalt, Central Germany. Palaeodiversity and Palaeoenvironment, 90, 153–162.

    Google Scholar 

  • Winkler, D. E., & Kaiser, T. M. (2015). Uneven distribution of enamel in the tooth crown of a plains Zebra (Equus quagga). PeerJ, 3, e1002.

    Google Scholar 

  • Wright, B. W., Ulibarri, L., O’Brian, J., Sadler, B., Prodhan, R., Covert, H. H., & Nadler, T. (2008). It's tough out there: variation in the toughness of ingested leaves and feeding behavior among four Colobinae in Vietnam. International Journal of Primatology, 29, 1455–1466.

    Google Scholar 

Download references

Acknowledgements

We would like to thank Wighart von Koenigswald and Thomas Martin for support and advice. We are grateful to all members of the DFG Research Unit 771 for fruitful discussions. We thank the people being in charge for the collections used: D. Bohaska (Smithsonian National Museum of Natural History Washington D.C), L. Costeur and M. Schneider (Naturhistorisches Museum Basel), J. Galkin (American Museum of Natural History New York), P. Gingerich (University of Michigan), E. Milsom and M. Blume (Hessisches Landesmuseum Darmstadt), K. Rose (Johns Hopkins University Baltimore), G. Rößner (Bayerische Staatssammlung für Paläontologie und Geologie der LMU München), S. Schaal, J. Habersetzer, E. Brahm and M. Ackermann (Senckenberg Forschungsinstitut und Naturmuseum Frankfurt), R. Schellhorn (Steinmann-Institut, Universität Bonn), S. Shelton (Museum of Geology South Dakota School of Mines & Technology Rapid City), R. Ziegler (Staatliches Naturkunde Museum Stuttgart). We thank Krister T. Smith for his help and suggestions that improved the manuscript. We are deeply grateful to Mikael Fortelius, Christine M. Janis and one anonymous reviewer for their helpful and valuable comments. This is publication no. 99 of the DFG Research Unit 771.

Funding

The project is part of the DFG Research Unit 771 and was funded by the Deutsche Forschungsgemeinschaft (DFG For771-project D2).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sandra Engels.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Engels, S., Schultz, J.A. Evolution of the power stroke in early Equoidea (Perissodactyla, Mammalia). Palaeobio Palaeoenv 99, 271–291 (2019). https://doi.org/10.1007/s12549-018-0341-4

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12549-018-0341-4

Keywords

Navigation