Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603990
Title: Ruminant palaeodietary reconstruction using occlusal morphology of upper molars
Author: Heywood, J. J. N.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2009
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Abstract:
The study takes an ecomorphological approach to the reconstruction of ruminant diets using the occlusal surface of upper molars. A multivariate approach was used to characterise ruminants of different diets using traits of the exposed enamel ridges and dentine basins. The study also employed a means of control for phylogenetic non-independence, performing the analyses at each taxonomic level from infraorder to tribe. This approach allowed an assessment of the levels of convergent evolution to the same diets within separate taxonomic units. At every level of analysis, bovids of different diets were more clearly distinguishable according to their occlusal morphology than cervids. Lower taxonomic levels generally also gave better classification results than higher ones. It is concluded that ecomorphological analyses may be influenced adversely if the ecological and phylogenetic history of the sample is not considered. Bovid browsers were generally characterised by thinner enamel ridges, especially thin buccal protocone ridges (R3), wide protocones and enamel alignment related to body size. Grazer enamel is thick, long and aligned more parallel to the chewing direction. Browse dominated and mixed feeders with equal levels of browse and grass clustered with browsers. Grass dominated mixed feeders approach the morphology of, but did not cluster amongst grazers. Interspecific morphology varied less in the Cervidae. This is correlated with lower ecological and taxonomic diversity, an absence from open and arid habitats, and low hypsodonty (crown height) compared with bovids. Links between these are considered in terms of historical biogeography and morphological constraint. The ‘cusp fusion hypothesis’ is put forward to explain the failure of cervids to exploit the increasingly arid habitats of the Neogene.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.603990  DOI: Not available
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