Buccal dental-microwear and feeding ecology of Early Pleistocene Theropithecus oswaldi from Cueva Victoria (Spain)

Paleontologists use fossil teeth to reconstruct the diets of early hominins and other extinct species. Some evidence is adaptive: nature selects for tooth size, shape, and structure best suited to specific food types. Other evidence includes traces left by actual foods eaten, such as microscopic tooth wear. This critical review considers how molars work, how they are used, and how occlusal topography and dental microwear can be used to infer diet and food preferences in the past, particularly for hominins of the Pliocene and early Pleistocene. Understanding that cheek teeth function as guides for chewing and tools for fracturing allows us to characterize aspects of occlusal form that reflect mechanical properties of foods to which a species is adapted. Living primates that often eat leaves, for example, have longer crests and more sloping occlusal surfaces than those that prefer hard foods. Studies of feeding ecology have shown, however, that tooth shape does not always correspond to preferred food items. It often follows mechanically challenging foods whether eaten often or rarely. Other lines of evidence that reflect actual tooth use are required to work out food preferences. Microwear textures, for example, reflect foods eaten by individuals in the past such that hard seeds and bone tend to leave complex, pitted surface textures, whereas tough leaves and meat more often leave anisotropic ones covered in long, parallel scratches. The study of fossil hominin molars shows how these various attributes are combined to infer diet and food preference in the past. A trend in occlusal morphology suggests decreased dietary specialization from Australopithecus to early Homo, and increasing dispersion in microwear complexity values is consistent with this. On the other hand, occlusal morphology may suggest dietary specialization in Paranthropus, although different species of this genus have different microwear texture patterns despite similar craniodental adaptations.

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Dental microwear textural analyses to track feeding ecology of reindeer: a comparison of two contrasting populations in Norway

Mammal Research ◽

10.1007/s13364-016-0304-y ◽

2016 ◽

Vol 62 (1) ◽

pp. 111-120 ◽

Cited By ~ 3

Author(s):

Olivier Bignon-lau ◽

Natacha Catz ◽

Emilie Berlioz ◽

Vebjørn Veiberg ◽

Olav Strand ◽

...

Keyword(s):

Feeding Ecology ◽

Dental Microwear ◽

Textural Analyses

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Feeding ecology of Eucladoceros ctenoides as a proxy to track regional environmental variations in Europe during the early Pleistocene

Comptes Rendus Palevol ◽

10.1016/j.crpv.2017.07.002 ◽

2018 ◽

Vol 17 (4-5) ◽

pp. 320-332 ◽

Cited By ~ 7

Author(s):

Émilie Berlioz ◽

Dimitris S. Kostopoulos ◽

Cécile Blondel ◽

Gildas Merceron

Keyword(s):

Feeding Ecology ◽

Early Pleistocene ◽

Environmental Variations ◽

Eucladoceros Ctenoides

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Microwear–mesowear congruence and mortality bias in rhinoceros mass-death assemblages

Paleobiology ◽

10.1017/pab.2017.13 ◽

2017 ◽

Vol 44 (1) ◽

pp. 131-154 ◽

Cited By ~ 9

Author(s):

Matthew C. Mihlbachler ◽

Daniel Campbell ◽

Charlotte Chen ◽

Michael Ayoub ◽

Pawandeep Kaur

Keyword(s):

Cause Of Death ◽

Seasonal Change ◽

Feeding Ecology ◽

Dental Microwear ◽

Dental Wear ◽

Ecological Stress ◽

Death Assemblages ◽

Fossil Assemblages ◽

Stochastic Events ◽

Ecological Disturbances

AbstractAlthough we do not know the cause of death of most fossil animals, mortality is often associated with ecological stress due to seasonality and other stochastic events (droughts, storms, volcanism) that may have caused shifts in feeding ecology preceding death. In these instances, dental microwear, which reflects feeding ecology in a narrow window of time, may provide a biased view of diet. Mesowear, another dental-wear proxy based on the morphology of worn cusps, requires macroscopic amounts of dental wear and reflects diet for a longer interval and may be less prone to bias from near-death ecological stress. We compared congruence between microwear and mesowear of North American, fossil rhinocerotid mass-death assemblages and collections of hunted modern rhinocerotids to test the hypothesis that fossil assemblages yield more incongruous microwear and mesowear data as a result of near-death ecological disturbances. In extant rhinos, both mesowear and microwear are associated with diet and height of the feeding environment. Mesowear and microwear in the modern rhinocerotid collections are statistically correlated, with strong relationships between average mesowear scores and labially distributed dental microwear. In contrast, a relationship between mesowear and microwear was not observed among the fossil rhinocerotid assemblages. Mesowear suggests that the fossil rhinos had low-abrasion diets, suggesting that they fed from clean, possibly tall vegetation. Some, but not all, mass-death assemblages produce microwear data with excessive scratches and/or pits compared with expectations based on mesowear results, suggesting that dental microwear was altered shortly before death in some but not all of the fossil assemblages. The dental-wear proxies available to paleoecologists provide a mosaic of dietary evidence reflecting diet over long (mesowear) and more abbreviated (microwear) periods of time that, together, provide a richer understanding of feeding ecology and its relationship to environment, seasonal change, and other ecological disturbances.

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