title: Opportunistic feeding strategy for the earliest old world hypsodont equids: evidence from stable isotope and dental wear proxies.
abstract: BACKGROUND
  The equid Hippotherium primigenium, with moderately hypsodont cheek teeth, rapidly dispersed through Eurasia in the early late Miocene. This dispersal of hipparions into the Old World represents a major faunal event during the Neogene. The reasons for this fast dispersal of H. primigenium within Europe are still unclear. Based on its hypsodonty, a high specialization in grazing is assumed although the feeding ecology of the earliest European hipparionines within a pure C3 plant ecosystem remains to be investigated.
  
  
  RESULTS
  A multi-proxy approach, combining carbon and oxygen isotopes from enamel as well as dental meso- and microwear analyses of cheek teeth, was used to characterize the diet of the earliest European H. primigenium populations from four early Late Miocene localities in Germany (Eppelsheim, Höwenegg), Switzerland (Charmoille), and France (Soblay). Enamel δ(13)C values indicate a pure C3 plant diet with small (<1.4‰) seasonal variations for all four H. primigenium populations. Dental wear and carbon isotope compositions are compatible with dietary differences. Except for the Höwenegg hipparionines, dental microwear data indicate a browse-dominated diet. By contrast, the tooth mesowear patterns of all populations range from low to high abrasion suggesting a wide spectrum of food resources.
  
  
  CONCLUSIONS
  Combined dental wear and stable isotope analysis enables refined palaeodietary reconstructions in C3 ecosystems. Different H. primigenium populations in Europe had a large spectrum of feeding habits with a high browsing component. The combination of specialized phenotypes such as hypsodont cheek teeth with a wide spectrum of diet illustrates a new example of the Liem's paradox. This dietary flexibility associated with the capability to exploit abrasive food such as grasses probably contributed to the rapid dispersal of hipparionines from North America into Eurasia and the fast replacement of the brachydont equid Anchitherium by the hypsodont H. primigenium in Europe.
authors.affiliation: Steinmann-Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Tütken
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Kaiser
authors.forename: Torsten
authors.initials: T
authors.lastname: Vennemann
authors.forename: Gildas
authors.initials: G
authors.lastname: Merceron
mesh_terms: D063147:Animal Distribution; D000818:Animals; D002247:Carbon Isotopes; D003743:Dental Enamel / Q000033:anatomy & histology / Q000737:chemistry / Q000502:physiology*; D004032:Diet; D017753:Ecosystem; D018397:Equidae / Q000033:anatomy & histology / Q000502:physiology*; D005060:Europe; D053476:Extinction, Biological; D005247:Feeding Behavior / Q000502:physiology*; D005580:Fossils; D060434:Herbivory / Q000502:physiology*; D009656:North America; D010103:Oxygen Isotopes; D058974:Phylogeography; D006109:Poaceae; D014070:Tooth / Q000033:anatomy & histology / Q000737:chemistry / Q000502:physiology*; D057085:Tooth Wear
chemical_list: D002247:Carbon Isotopes; D010103:Oxygen Isotopes
references.citation: Rapid Commun Mass Spectrom. 2003;17(9):1004-6
references.pmid: 12717777
references.citation: Evolution. 2010 Feb 1;64(2):398-408
references.pmid: 19735525
references.citation: Proc Natl Acad Sci U S A. 2006 Jul 25;103(30):11201-5
references.pmid: 16840554
references.citation: Proc Biol Sci. 2010 Oct 22;277(1697):3105-12
references.pmid: 20519220
references.citation: Science. 2005 Mar 18;307(5716):1728-30
references.pmid: 15774746
references.citation: Oecologia. 1997 Oct;112(3):285-299
references.pmid: 28307475
references.citation: Proc Biol Sci. 2011 Jun 7;278(1712):1742-7
references.pmid: 21068036
references.citation: Nature. 1981 Jul 23;292(5821):333-5
references.pmid: 7019719
references.citation: PLoS One. 2013;8(2):e56167
references.pmid: 23405263
references.citation: Oecologia. 2004 Jan;138(1):5-12
references.pmid: 14530961
references.citation: Am J Phys Anthropol. 2012 Apr;147(4):551-79
references.pmid: 22331579
references.citation: J Morphol. 2003 Oct;258(1):67-83
references.pmid: 12905535
references.citation: Proc Natl Acad Sci U S A. 2010 Nov 16;107(46):19691-5
references.pmid: 21041671
references.citation: Biol Rev Camb Philos Soc. 2011 Aug;86(3):733-58
references.pmid: 21418504
references.citation: Science. 1978 Sep 8;201(4359):908-10
references.pmid: 684415
references.citation: Am Nat. 1998 Mar;151(3):223-35
references.pmid: 18811353
references.citation: Science. 1999 Feb 5;283(5403):824-7
references.pmid: 9933161
references.citation: Nature. 2002 May 30;417(6888):538-40
references.pmid: 12037565
references.citation: Am J Phys Anthropol. 1989 Dec;80(4):447-60
references.pmid: 2513725
references.citation: PLoS One. 2011;6(11):e27392
references.pmid: 22076156
references.citation: J R Soc Interface. 2013 Jan 09;10(80):20120923
references.pmid: 23303220
references.citation: J Hum Evol. 2007 Oct;53(4):331-49
references.pmid: 17719619
references.citation: Oecologia. 1999 Aug;120(3):347-363
references.pmid: 28308012
references.citation: PLoS One. 2012;7(5):e36817
references.pmid: 22615819
references.citation: Proc Natl Acad Sci U S A. 2010 Mar 30;107(13):5738-43
references.pmid: 20231481
references.citation: Am J Phys Anthropol. 1999 Mar;108(3):359-73
references.pmid: 10096686
references.citation: Am J Phys Anthropol. 2001 Feb;114(2):124-38
references.pmid: 11169902
references.citation: Science. 2011 Mar 4;331(6021):1178-81
references.pmid: 21385712
references.citation: Am J Phys Anthropol. 1989 Nov;80(3):391-401
references.pmid: 2686463
references.citation: PLoS One. 2010 Mar 04;5(3):e9542
references.pmid: 20209051
references.citation: J Hum Evol. 2005 Oct;49(4):482-98
references.pmid: 16085279