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Proboscideans are so-called ecosystem engineers and are considered key players in hypotheses about Late Pleistocene megafaunal extinctions. However, knowledge about the autoecology and chronology of the proboscideans in South America is still open to debate and raises controversial views. Here, we used a range of multiproxy approaches and new radiocarbon datings to study the autoecology of Chilean gomphotheres, the only group of proboscideans to reach South America during the Great American Biotic Interchange (~3.1 to 2.7 million years before present). As part of this study, we analyzed stable isotopes, dental microwear, and dental calculus microfossils on gomphothere molars from 30 Late Pleistocene sites (31° to 42°S). These proxies provided different scales of temporal resolution, which were then combined to assess the dietary and habitat patterns of these proboscideans. The multiproxy study suggests that most foraging took place in relatively closed environments. In Central Chile, there is a positive correlation between lower δ13C values and an increasing consumption of arboreal/scrub elements. Analyses of dental microwear and calculus microfossils have verified these leaf-browsing feeding habits. From a comparative perspective, the dietary pattern of South American gomphotheres appears to be constrained more by resource availability than by the potential dietary range of the individual taxa. This multiproxy study is aimed at increasing knowledge of the life history of gomphotheres and thus follows an issue considered one of the greatest challenges for paleontology in South America, recently pointed out by the need to thoroughly understand the role of ecological engineers before making predictions about the consequences of ecosystem defaunation. [ABSTRACT FROM AUTHOR]

Mastication causes distinct use wear scars on teeth that can aid in dietary reconstructions of fossils. However, the role played by exogenous grit in dental wear complicates the association between wear and diet. Dental wear analyses often assume that foods closer to the soil contain more exogenous grit than those in the forest canopy. Yet, a layer of leaf litter covering many forest floors may trap grit from the soil, keeping it from settling on surrounding vegetation or becoming part of atmospheric dust. Cercocebus atys is frequently referenced in dental wear studies because of its dependence on hard Sacoglottis gabonensis seeds collected from the forest floor. Here we examine quantities of dust deposition at different forest levels and assess its potential role in wear patterns observed in C. atys. We collected grit from S. gabonensis seeds (N = 64) found under the leaf litter and compared them to grit samples taken from the surface of leaves at different forest strata (N = 450) in Ivory Coast’s Taï National Park. Seeds underneath the leaf litter were coated with significantly more grit than leaves above the leaf material and we conclude that leaf litter is a significant barrier to grit particles originating from the soil. Given that evidence points to a significant difference in grit amount between foodstuffs on the ground and foods near the ground, the findings lead to a prediction of differences in dental wear patterns between purely arboreal foragers and those incorporating terrestrial food sources. [ABSTRACT FROM AUTHOR]

To better understand the environmental conditions that prevailed in the Plio-Pleistocene Shungura Formation, Lower Omo Valley, Ethiopia, we analyze the feeding preferences of Tragelaphini, the third most common tribe of Shungura bovids. Molar mesowear and dental microwear texture analyses were applied to three species ( Tragelaphus rastafari , T. nakuae , and T. gaudryi ) and body mass estimates were calculated for the T. rastafari-nakuae lineage to test whether dietary shifts were linked to body mass changes. We compare our results with previous work on stable carbon isotopes (δ 13 C) of enamel, which indicated that tragelaphins from the Shungura Formation possessed dietary flexibility. We found that the both the T. rastafari-nakuae lineage and T. gaudryi maintained a mixed feeding dietary niche, with varying proportions of C 3 versus C 4 inputs, from ~3.6 to >2 Ma. Our results show that T. rastafari consumed more browse than its descendant, T. nakuae , which was a mixed feeder consuming a greater proportion of C 4 dicots ~ 2.8 Ma. The T. rastafari - T. nakuae dietary shift may reflect environmental changes in the Shungura Formation during this time, but appears to be offset from body mass increases in this lineage, which occurred gradually through the Plio-Pleistocene. This study highlights the importance of a multi-proxy approach to precisely determine the dietary ecologies of extinct bovids and points to how each proxy offers a slightly different perspective on the ecology of fossil organisms. [ABSTRACT FROM AUTHOR]

The study of convergences in mammals is crucial to understand the evolutionary processes underlying the origin of shared traits. A classic example is the independent evolution in the pygmy rock-wallaby, the silvery mole-rat, and manatees of continuous dental replacement to compensate for high dental wear. The origins of continuous dental replacement in mammals remain unresolved. As the functional study of a trait may permit pinpointing the adaptive nature of its independent evolution, we aimed at comparing first the morpho-functional characteristics of the masticatory apparatus between the pygmy rock-wallaby and their closest relatives, and then with some published data on the silvery mole-rat. 3D geometric morphometric and biomechanical analyses were complemented by dental microwear analyses. Our results showed that the pygmy rock-wallaby clearly departs from its relatives in having a wider skull, a shorter snout, and a dentition situated more distally. These cranial modifications, previously observed in the silvery mole-rat, are probably linked with a neotenic development. Because of higher developmental constraints on marsupial skulls, such adjustment in the pygmy rock-wallaby may have improved the force generated by adductor muscles at molars for comminution of tough and abrasive plants. In contrast, the strong attrition combined with the ingestion of dust during high activity of digging and feeding might contribute to both molar damage and high wear in the silvery mole-rat. Our results stress the importance of combining morphological, developmental, and functional data to show that different behaviors related to ecology can explain the convergent occurrence of continuous dental replacement in mammals. [ABSTRACT FROM AUTHOR]

Change in Mediterranean grinding technology during the Hellenistic/Roman period affected the pattern of dental microwear since external grit particles were finer when flour was prepared using large rotary querns. Therefore, it is possible to detect the technological change through the analysis of human dentition. Here, the sample of teeth from Kültepe (ancient Kanesh), Turkey, is investigated to determine if the grinding technology changed at this site between the Middle Bronze Age ( n = 12) and Hellenistic/Roman period ( n = 4). A Hellenistic/Roman sample from Assos ( n = 7) is also included for comparative purposes. The proportions and size of linear and nonlinear features did not differ significantly between periods or sites, which indicates that in spite of technical advances, old grinding technologies were still used in the Hellenistic/Roman period in Anatolia. [ABSTRACT FROM AUTHOR]

Microscopic wear patterns on teeth, that is, dental microwear, are capable of recording observed dietary behaviour in a diversity of extant and extinct animals. However, recent work has questioned the utility of dental microwear at clarifying dietary behaviour, instead suggesting that dental microwear textures are reflective of grit consumed and not the dietary properties of ingested food. Some suggest that dental microwear cannot reflect the textural properties of vegetation consumed because phytoliths are too soft to form microwear. Koalas ( Phascolarctos cinereus) are model organisms for examining dental microwear formation because they consume a specialized diet consisting almost exclusively of eucalyptus leaves, which notably lack phytoliths. Here, we assess if koala dental microwear records a diet consistent with the consumption of tough leaves - despite the absence of phytoliths in their primary food source. Dental microwear texture data of koalas are consistent with tough folivorous diets, with high anisotropy values indistinguishable from folivorous primates and grazing bovids. However, koalas have significantly higher complexity (indicative of hard object feeding) than the folivorous primate Alouatta palliata, and are indistinguishable in this variable from mixed feeding and browsing bovids. While higher complexity values in koalas may result from increased dust and/or grit on the landscape in comparison to folivores that occur in wetter environments, it may also result from the mastication of woody browse. We also determined that complexity and textural fill volume are not significantly greater in drier environments - as one would predict if grit was the major contributor to dental microwear formation. Koalas may instead be selecting softer younger leaves in drier regions where water is more limited. Collectively, microwear associated with tough object feeding can be formed in the absence of phytoliths and grit may interact with food to form microwear reflective of diet, as opposed to overprinting dietary signals. [ABSTRACT FROM AUTHOR]

The La Brea Tar Pits are a highly fossiliferous late Pleistocene locality, with over 230 vertebrate species, and the potential to help clarify the ecology of Pleistocene megafauna prior to their extinction. Here, we analyze dental microwear textures, dental mesowear, and stable carbon isotopes to assess the dietary behavior of the three most abundant ungulates at La Brea. We examined Bison antiquus , Camelops hesternus , and Equus occidentalis teeth from pits spanning the latest Pleistocene, focusing on pit 77 (~ 35 Ka, glacial period), and pits 61/67 (~ 11.5 Ka, interglacial period). Dental microwear attributes demonstrate that B . antiquus and E . occidentalis consumed foods with similar textural properties to those preferred by mixed feeding and browsing bovids, as well as significantly different food textures than the diet of modern bison and horses. Camelops hesternus has attributes most similar to modern browsing bovids and giraffes, revealing that all taxa studied likely consumed at least some woody browse. Complexity values ( Asfc ) in B . antiquus and E . occidentalis are significantly greater at pit 77 than at pits 61/67 and modern populations, suggesting a dietary decrease in woody vegetation and shrubs from the glacial to interglacial period. Dental mesowear values further indicate that B . antiquus and C . hesternus consumed woody vegetation, whereas E . occidentalis grazed. The different dietary interpretation for E . occidentalis may reflect a discrepancy between its average diet inferred from mesowear and its most recent diet inferred from microwear. Lastly, stable carbon isotopes reveal diets composed mostly of C 3 vegetation, with B . antiquus incorporating significantly more C 4 vegetation than either of the other dominant herbivores during the accumulation of both assemblages. Collectively, these data suggest that the dietary ecology of the dominant La Brea herbivores was more nuanced than previously thought, shifting coincident with changing climates, and not necessarily predictable from morphology or any one proxy method. [ABSTRACT FROM AUTHOR]

Extensive oral processing of food through dental occlusion and orbital mandibular movement is often cited as a uniquely mammalian trait that contributed to their evolutionary success. Save for mandibular translation, these adaptations are not seen in extant archosaurs or lepidosaurs. In contrast, some ornithischian dinosaurs show evidence of precise dental occlusion, habitual intraoral trituration and complex jaw motion. To date, however, a robust understanding of the diversity of jaw mechanics within non-avian dinosaurs, and its comparison with other vertebrates, remains unrealized. Large dental batteries, well-developed dental wear facets, and robust jaws suggests that neoceratopsian (horned) dinosaurs were capable chewers. But, biomechanical analyses have assumed a relatively simple, scissor-like (orthal) jaw mechanism for these animals. New analyses of dental microwear, presented here, show curvilinear striations on the teeth of Leptoceratops. These features indicate a rostral to caudal orbital motion of the mandible during chewing. A rostrocaudal mandibular orbit is seen in multituberculates, haramiyid allotherians, and some rodents, and its identification in Leptoceratops gracilis is the first evidence of complex, mammal-like chewing in a ceratopsian dinosaur. The term circumpalinal is here proposed to distinguish this new style of chewing from other models of ceratopsian mastication that also involve a palinal component. This previously unrecognized complexity in dinosaurian jaw mechanics indicates that some neoceratopsian dinosaurs achieved a mammalian level of masticatory efficiency through novel adaptive solutions.

Anthracotheres and entelodonts are large mammals with peculiar morphological characteristics that combine plesiomorphic and derived features. The unusual anatomy of anthracotheres shows a morphological resemblance to pigs and hippos and their bunoselenodont low-crowned molars have been interpreted as an adaptation to frugivorous/folivorous diets. Entelodonts share cranial and dental similarities to pigs and carnivores, and this has been interpreted as an adaption to opportunistic omnivore diets, hunting/scavenging, or bone-crushing (cf. hyenas). The objective of the present study is to use dental microwear analysis to test these assumptions and to infer the diet of anthracotheres and entelodonts. Dental microwear was quantified on the upper and lower molars using a stereomicroscope. To assess the dietary traits of the fossil samples, the results were compared to a dataset of extant large mammals covering ten dietary categories. The microwear features indicate different diets for Anthracotherium sp. and Entelodon magnus. Our sample of entelodonts shows an omnivorous diet similar to that of the wild boar, and it probably varied considerably between seasons. The anthracotheres we analysed were opportunistic browsing, frugivore, and grazing herbivores. During the Oligocene, these two taxa occupied ecological niches characterised by a large diversity of food resources. The results of the study offer further insights into the characteristics of the digestive system in fossil artiodactyls. The large dataset used in this research opens new perspectives for the dietary reconstruction of poorly known mammal taxa by considering a wide range of diets. • First dental microwear analysis of Oligocene entelodonts and anthracotheres. • Entelodonts had an omnivorous diet similar to that of the extant wild boar. • Anthracotheres were opportunistic herbivores (browsers, frugivores and grazers). • The dietary traits show the availability of a large diversity of food resources. [ABSTRACT FROM AUTHOR]

The diet of the extinct European cave bear, Ursus spelaeus, has widely been debated. Diverging from the extant brown bear (Ursus arctos) approximately 1.2 million years ago, the cave bear is one of the most ubiquitous fossil bears occurring in Europe during the Middle and Late Pleistocene. Early morphological studies suggested that the cave bear was likely specialized on processing tough and/or abrasive foods, while later two-dimensional low-magnification microwear studies suggested that they were omnivorous and may have consumed more bone than U. arctos. Here, we used dental microwear texture analysis (DMTA) to further interpret the diet of the cave bear. Microscopic wear features were assessed and compared to modern ursids, including the cave bears' closest living relative, U. arctos. Results suggest that U. spelaeus consumed a diet with a diversity of textural properties, similar to most other bears and only distinguishable from the hyper-carnivorous polar bear (Ursus maritimus). Further, only U. maritimus can be distinguished from all bear species here examined (i.e., the giant panda bear, Ailuropoda melanoleuca; sun-bear, Ursus malayanus; spectacled bear, Tremarctos ornatus; American black bear, Ursus americanus; and U. arctos), with significantly greater area-scale fractal complexity (Asfc) of microwear surfaces. The DMTA of A. melanoleuca also has significantly lower Asfc than T. ornatus and U. americanus, consistent with observed dietary behavior. As modern bears vary their diets seasonally and across their range, it may be difficult to characterize the dietary ecology of extinct bears using dental microwear alone. Nevertheless, DMTA here demonstrates that U. spelaeus had a diet distinct from the hyper-carnivorous U. maritimus and instead likely consumed food with textural properties most similar to other herbivorous/omnivorous bears. Lastly, the European cave bear and North American giant short-faced bear (Arctodus simus) may have had similar diets as evident from DMTA, with U. spelaeus potentially eating tougher food items. [ABSTRACT FROM AUTHOR]

This study conducted the first three dimensional microwear texture analysis of human deciduous teeth to reconstruct the physical properties of medieval childhood diet (age 1–8yrs) at St Gregory's Priory and Cemetery (11th to 16th century AD) in Canterbury, England. Occlusal texture complexity surfaces of maxillary molars from juvenile skeletons ( n = 44) were examined to assess dietary hardness. Anisotropy values were calculated to reconstruct dietary toughness, as well as jaw movements during chewing. Evidence of weaning was sought, and variation in the physical properties of food was assessed against age and socio-economic status. Results indicate that weaning had already commenced in the youngest children. Diet became tougher from four years of age, and harder from age six. Variation in microwear texture surfaces was related to historical textual evidence that refers to lifestyle developments for these age groups. Diet did not vary with socio-economic status, which differs to previously reported patterns for adults. We conclude, microwear texture analyses can provide a non-destructive tool for revealing subtle aspects of childhood diet in the past. [ABSTRACT FROM AUTHOR]

It is axiomatic that knowledge of the diets of extinct hominin species is central to any understanding of their ecology and our evolution. The importance of diet in the paleontological realm has led to the employment of multiple approaches in its elucidation. Some of these have deep historical roots, while others are dependent upon more recent technical and methodological advances. Historically, studies of tooth size, shape, and structure have been the gold standard for reconstructing diet. They focus on species-level adaptations, and as such, they can set theoretical brackets for dietary capabilities within the context of specific evolutionary moments. Other methods (e.g., analyses of dental calculus, biogeochemistry, and dental microwear) have only been developed within the past few decades, but are now beginning to yield evidence of the actual foods consumed by individuals represented by fossil remains. Here we begin by looking at these more "direct" forms of evidence of diet before showing that, when used in conjunction with other techniques, these "multi-proxy" approaches can raise questions about traditional interpretations of early hominin diets and change the nature of paleobiological interpretations.

Paleoanthropologists and vertebrate paleontologists have for decades debated the etiology of tooth wear and its implications for understanding the diets of human ancestors and other extinct mammals. The debate has recently taken a twist, calling into question the efficacy of dental microwear to reveal diet. Some argue that endogenous abrasives in plants (opal phytoliths) are too soft to abrade enamel, and that tooth wear is caused principally by exogenous quartz grit on food. If so, variation in microwear among fossil species may relate more to habitat than diet. This has important implications for paleobiologists because microwear is a common proxy for diets of fossil species. Here we reexamine the notion that particles softer than enamel (e.g., silica phytoliths) do not wear teeth. We scored human enamel using a microfabrication instrument fitted with soft particles (aluminum and brass spheres) and an atomic force microscope (AFM) fitted with silica particles under fixed normal loads, sliding speeds, and spans. Resulting damage was measured by AFM, and morphology and composition of debris were determined by scanning electron microscopy with energy-dispersive X-ray spectroscopy. Enamel chips removed from the surface demonstrate that softer particles produce wear under conditions mimicking chewing. Previous models posited that such particles rub enamel and create ridges alongside indentations without tissue removal. We propose that although these models hold for deformable metal surfaces, enamel works differently. Hydroxyapatite crystallites are "glued" together by proteins, and tissue removal requires only that contact pressure be sufficient to break the bonds holding enamel together. [ABSTRACT FROM AUTHOR]

Xenarthran teeth are rootless and continuously growing. They lack an outer enamel layer and consist instead of a combination of 2 generally different varieties of dentine with or without an outer collar of cementum. This dental make-up is unique among mammals. In the last decade, xenarthran teeth have been subject to a number of studies regarding microscopic features, including analyses of microstructure and microwear patterns. Here, we present a review of the present knowledge in these 2 fields together with new results on feeding adaptations in the giant ground sloth, Megatherium americanum. Microwear patterns suggest that M. americanum fed mainly on plants with low to moderate intrinsic toughness, although we observe a trend that microwear patterns in extinct sloths may reflect habitat (i.e., feeding in open habitats with higher amounts of grit versus closed habitats with lower amounts of grit) as much as, if not more than, the texture of ingested food. [ABSTRACT FROM AUTHOR]

Dietary habits are inferred from dental microwear and isotope analyses of the Magdalenian human individual from the site of El Mirón, dated to 15,460 ± 40 BP. The pattern of dental microwear was established on the buccal surface of the lower fourth premolar and on the bottom of facet 9 on the occlusal surface of the lower third molar. The results obtained through analysis of different surfaces are consistent and indicate a mixed diet for this Lower Magdalenian individual, including meat, aquatic resources and vegetables. These results are in agreement with those obtained through isotope analysis. This implies a generalized exploitation of the environment as has been previously established in other Late Upper Palaeolithic specimens. [ABSTRACT FROM AUTHOR]

Pleistocene Paranthropus robustus fossils from Swartkrans have yielded stable isotope values suggesting some foraging on C4 plants possibly including underground storage organs. Dental microwear texture analysis on P. robustus (SK 6, SK 34 and SK 47) from Swartkrans Member 1 is performed to examine whether tooth surface damage from mastication agrees with prior dietary inferences from carbon isotopes. There is considerable variation in textural characteristics among the P. robustus specimens. Specifically, adult SK 34 stands apart from the two subadult specimens, SK 6 and SK 47, suggesting life history could be reflected in patterns of dental microwear texture characteristics, although seasonality and availability of fallback foods may also explain the variation observed in P. robustus. The fossils all exhibit elevated surface texture complexity, resembling the values for Lophocebus albigena and Cebus apella, and to a lesser extent, Pan troglodytes. Paranthropus robustus is dissimilar to primary folivores, such as Trachypithecus cristatus or folivore- frugivores such as Alouatta palliata suggesting leaves comprised very little of its diet. The textural fill volume of P. robustus differs from that observed in extant primates from tropical forests indicating extreme durophagy, perhaps a function of differences in habitat. Ingestion of extraneous grit on the underground parts of plants and from terrestrial resources, perhaps as fallback foods or as dietary staples, may account for these enamel textural properties and may help explain the mixed C3/C4 isotopic signal in P. robustus. [ABSTRACT FROM AUTHOR]

Objectives The purpose of this investigation was to explore the role and interplay that bite force has on the formation of microwear features upon the dentition of two- and three-fingered tree sloths ( Choloepus and Bradypus , respectively), with the hypothesis that increasing relative bite force would correlate with an increase in frequency of microwear features. Design Microwear patterns were assessed by counting features (e.g. scratches, pits) seen within a standardized field of view on the mesio-labial facets casts of upper molariform series from sloth specimens using Scanning Electron Microscopy. Relative bite force was estimated using a geometric model to quantify the muscular inputs of the temporalis and masseter muscles with respect to the mandible at the centre of each lower tooth. Results Although relative bite force increases posteriorly along the toothrow, there is not a significant increase in frequency of scratches or pits in either sloth. Scratch width increases significantly as bite force increases in Choloepus . Conclusions We reject the hypothesis that higher magnitude of bite force is correlated with an increased number of microwear features in tree sloths. Results here suggest that other endogenous variables (such as chewing direction, manipulation of food during mastication, amount of food ingested) play a more significant role in the formation of microwear in sloths than orthal closure force. This further supports the formation of microwear on teeth as an intricate process that has multiple influences beyond the texture of food particles. [ABSTRACT FROM AUTHOR]

Currently, very little is known about the ecology of extinct Eurasian cercopithecids. Dietary information is crucial in understanding the ecological adaptations and diversity of extinct cercopithecids and the evolution of this family. For example, the colobine genus Dolichopithecus is represented by multiple large-bodied species that inhabited Eurasia during the Pliocene-Early Pleistocene. The available evidence, though limited, suggests semiterrestrial locomotion, which contrasts with most extant African and Asian colobines that exhibit morphological and physiological adaptations for arboreality and folivory. These differences raise questions regarding the dietary specialization of early colobine taxa and how/if that influenced their dispersion out of Africa and into Eurasia. To further our understanding of the ecology of Plio-Pleistocene cercopithecids, we characterized the dental capabilities and potential dietary adaptations of Dolichopithecus ruscinensis through dental topographic and enamel thickness analyses on an M1 from the locality of Serrat d'en Vacquer, Perpignan (France). We also assessed the feeding behavior of D. ruscinensis through dental microwear texture analysis on a broad sample of fossil molars from fossil sites in France, Greece, Bulgaria, and Romania. Dental topographic and enamel thickness analyses suggest that D. ruscinensis could efficiently process a wide range of foods. Results of the dental microwear texture analysis suggest that its diet ranged from folivory to the consumption of more mechanically challenging foods. Collectively, this suggests a more opportunistic feeding behavior for Dolichopithecus than characteristic of most extant colobines. [ABSTRACT FROM AUTHOR]

Ontogenetic niche shifts, the phenomenon whereby animals change their resource use with growth, were probably widespread in dinosaurs, but most studies of duck-billed dinosaur ontogeny have so far focused mainly on the development of the cranial ornamentation. Here, we quantify allometry of 13 ecomorphological variables of the skull and examine tooth microwear in a sample of North American hadrosaurids to better understand their ecological functioning with growth. Our results indicate that, consistent with the Jarman-Bell principle relating body size to fibre intake and feeding selectivity, juvenile hadrosaurids were relatively more selective than their adult counterparts and subsisted on softer, low-growing browse cropped using lateral rotations of the neck. Chewing movements of the jaw probably did not differ greatly between growth stages. Our findings invite further investigation relating to cranial ontogenetic allometry in hadrosauromorphs more broadly, and to the possible role of ontogenetic niche shifts in the size structuring of Late Cretaceous herbivore communities. • Morphometric changes within the skull indicates dietary changes during growth. • Juveniles selectively fed on softer, lower-growing vegetation than adults. • Juvenile skulls may have been more kinetic than those of adults. [ABSTRACT FROM AUTHOR]

There has been much discussion of the role of behaviour in evolution, especially its potential to lead morphological evolution by placing the organism in a novel selective environment. Many adaptations of living species can be imagined to have originated in this way, although documented examples are relatively few. A fruitful arena for testing hypotheses about behavioural innovation is the fossil record. Traditionally, the behaviour of fossil species has been deduced from their morphology, precluding the observation of a behavioural lead preceding morphological evolution. This circularity can be broken by examining behavioural proxies independent of the adaptive morphology itself. Examples applicable to fossil remains include dietary information (e.g. wear traces on teeth, stable isotopes) and trace fossils indicating locomotor mode (footprints). The signature of a behavioural lead would be an observed shift in behaviour from one horizon (or taxon) to another, followed later by a functionally-related morphological change. This pattern can be sought either in finely-stratified anagenetic sequences of fossils (stratophenetic approach) or among fossils with well-resolved species-level phylogenies (cladistic approach). An array of case studies from the literature is presented. These include feeding shifts in finely-resolved sequences of vertebrates ranging from freshwater fish to terrestrial ungulates, as well as locomotor changes crucial to major evolutionary transitions in the origin of tetrapods, birds, and humans. The latter examples highlight the role of behaviour in initiating exaptation (the requisitioning of structure for a new function). The case studies also illustrate the challenges of using fossil sequences to elucidate behavioural roles, including insufficient stratigraphic resolution and uncertainty over the adaptive function of observed traits. By the same token, they suggest criteria for choosing promising cases for research, as well as for formulating testable hypotheses about evolutionary modes. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 315-331. [ABSTRACT FROM AUTHOR]

Silesaurus opolensis belongs to Silesauridae, the closest sister group to dinosaurs. The present study analyzed the dental microwear patterns of Silesaurus opolensis. Low pit-to-scratch ratios imply they did not feed on hard objects. Unimodal distributions of both wear-facet and non-facet scratch orientations indicate simple orthal jaw movement. Scratch orientation and density differ between microscopic regions in Silesaurus, and unlike hadrosaurid dinosaurs, the microwear patterns of small areas are not identical to those of whole teeth. [ABSTRACT FROM AUTHOR]

Highlights: [•] Herd management patterns increase understanding of one Neolithic cattle skull ring. [•] Isotopes in cattle dentition point to multiple juvenile management strategies. [•] Dental microwear data in the same cattle indicate a common seasonal diet at death. [•] Evidence suggests cattle were reared separately but died together. [•] Separate herding groups contributed cattle in a networking ritual slaughter. [ABSTRACT FROM AUTHOR]

Use-wear analysis is a method in archeology and paleoanthropology that identifies the functions of tools and teeth by closely examining the characteristics of their surface damage. Thus, microscopic tooth buccal wear helps to improve our knowledge of Prehistoric Man's way of life with regard to changing environments, resource usage, and technological practices. Aspects of buccal microwear analyzed in this study are restricted to the micro striae of the cheek teeth, which vary in number, length and orientation, evidencing major dietary patterns over long periods. Our information about human dietary history comes from the identification of different aspects of tooth micro striae observed in a variety of populations, ranging from the almost carnivorous to the largely vegetarian, even though the majority of humans depend to some extent on plant foods. The comparative examination of these surfaces on a large quantity of human remains, from the European Pleistocene to modern hunter-gatherers and today's urban people, show variability that can be explained eco-geographically as well as culturally, allowing the reconstruction of a grid or an atlas of major eating patterns reflecting different dietary traditions worldwide. The data hereby presented is the result of this approach which has been applied since 1976 to highlight these traces left by abrasive particles in the diet (La Préhistoire Française, edit. CNRS). As sources, we have used published papers where the authors have employed this methodology. The density of enamel buccal scratches gives an account of dietary changes in societies, horizontal to vertical striae proportions indicate the large dietary spectrum in Anatomically Modern Humans. The orientation of the striae patterns in specific sites points to aquatic foods consumed by our waterside Stone Age ancestors. [ABSTRACT FROM AUTHOR]

This study concerns the analysis of the dental microwear of 71 Easter Islanders who lived between the 13th and the 20th centuries and whose skeletons are housed in the Sebastian Englert Museum (Easter Island) as well as the Royal Institute of Natural Sciences of Belgium. The vestibular surface of the first and second permanent molars was examined by electron scanning microscope, at an enlargement of 178 times. The number of micro-striations, their length and their orientation were recorded in a circular area of 300 μm diameter using the Microware 4.02 program of P. Ungar. The pattern of microwear of the Easter Islanders indicates consumption of food which was not very abrasive, mainly of plant origin, which can be attributed to the important place held by sweet potatoes in their daily diet. A comparison with other populations previously studied (medieval and Neolithic populations in Belgium) indicates that the pattern of dental microwear of the Easter Islanders presents the most similarities with that of the Cistercians of the abbey of Dunes de Coxyde who consumed marine fish. Differences according to sex and age at death were not observed. Our study shows nevertheless that the so-called “royal” clan is distinguished from the other clans by its dental microwear. More consumption of products of animal origin by the socially privileged group could be the reason for this distinction.

Abstract: Bioarchaeology is a powerful tool in the examination of prehistoric collections of human skeletal remains. Application of a few bioarchaeological techniques (ancient DNA, carbon and nitrogen stable isotopes, and dental micro-wear) to the human osteological remains from the Early Neolithic LBK settlement of Vedrovice (Moravia), has allowed us to reconstruct not only broad cultural patterns but also the life histories of the individuals with insights into diet, migrations, ancestry, personal identity, social position and life experience. Vedrovice acted as a gateway settlement for a farming community with close ties to western Hungary and northeast Bohemia. The individuals showed clear differences in status and migration histories, giving glimpses of more complex social practices and patterns than could have been determined through the traditional culture-historical studies. [Copyright &y& Elsevier]

Most dental microwear texture studies to date have focused on enamel surfaces. However, for xenarthran microwear we must, in effect, "reinvent the wheel," because adult xenarthrans lack enamel. Dentin is softer than enamel and may record microwear differently. Thus, we aim to determine if dental microwear texture analysis (DMTA, which quantifies microwear in 3 dimensions) of dentin can yield biologically meaningful results by asking: do dentin and enamel in other eutherians record microwear texture the same way; and can DMTA differentiate between extant xenarthrans with different diets? We analyzed the carnassials of Florida panthers (Puma concolor coryi, n = 14), which have functional dentin and enamel, and found differences in texture fill volume and heterogeneity, suggesting that enamel and dentin DMTA cannot be directly compared. Next, we analyzed the teeth of sloths (Bradypus variegatus, n = 12; Choloepus hoffmanni, n = 9) and the 9-banded armadillo (Dasypus novemcinctus, n = 12), which differ in 2 attributes (surface complexity and fill volume) associated with food or abrasive properties. Other DMTA attributes show no differences between trophic groups, suggesting that dentin and enamel may differ in types of texture attributes that separate taxa by diet. [ABSTRACT FROM AUTHOR]

ABSTRACT Inference of feeding adaptation in extinct species is challenging, and reconstructions of the paleobiology of our ancestors have utilized an array of analytical approaches. Comparative anatomy and finite element analysis assist in bracketing the range of capabilities in taxa, while microwear and isotopic analyses give glimpses of individual behavior in the past. These myriad approaches have limitations, but each contributes incrementally toward the recognition of adaptation in the hominin fossil record. Microwear and stable isotope analysis together suggest that australopiths are not united by a single, increasingly specialized dietary adaptation. Their traditional (i.e., morphological) characterization as 'nutcrackers' may only apply to a single taxon, Paranthropus robustus. These inferences can be rejected if interpretation of microwear and isotopic data can be shown to be misguided or altogether erroneous. Alternatively, if these sources of inference are valid, it merely indicates that there are phylogenetic and developmental constraints on morphology. Inherently, finite element analysis is limited in its ability to identify adaptation in paleobiological contexts. Its application to the hominin fossil record to date demonstrates only that under similar loading conditions, the form of the stress field in the australopith facial skeleton differs from that in living primates. This observation, by itself, does not reveal feeding adaptation. Ontogenetic studies indicate that functional and evolutionary adaptation need not be conceptually isolated phenomena. Such a perspective helps to inject consideration of mechanobiological principles of bone formation into paleontological inferences. Finite element analysis must employ such principles to become an effective research tool in this context. Am J Phys Anthropol 151:356-371, 2013.© 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]