Presence of Hemitragus aff. cedrensis (Mammalia, Bovidae) in the Iberian Peninsula: Biochronological and biogeographical implications of its discovery at Bolomor Cave (Valencia, Spain)

The discovery of new material in Late Pleistocene levels at Bolomor Cave (Valencia, Spain) raises some questions about the presence of the most ancient record of Hemitragus cedrensis in the peninsula, and its dispersal out of Provence. The morphology and dimensions of some lower teeth confirm the identification of H. aff. cedrensis. Moreover, it presents strong similarities, both morphological and metrical, with the specimens from Caune de l’Arago and bau de l’Aubesier (end of OIS 7 to OIS 5e) rather than with the population from the eponymous locality. The data suggest a dispersal event out of Provence towards the Iberian Peninsula during the Eemian. This dispersal was not stopped by natural barriers such as large rivers, or mountains. The results presented here confirm the biochronological interest of the genus Hemitragus for the Late Pleistocene in Mediterranean Europe.     

Buccal dental microwear variability in extant African Hominoidea: taxonomy versus ecology

Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth molds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids’ diet and ecology.     

Equus mosbachensis tautavelensis nov. subsp.,un nouvel Equidae (Mammalia,Perissodactyla) du gisement pleistocene moyen ante-rissien de la Caune de l'Arago (Tautavel,Pyrenees Orientales,France)

The horse discovered in the upper sediments from the middle pleistocene site of La Caune de l'Arago, attributedin 1968 to Equus caballus mosbachensis, constitutes a particular sub-species: Equus mosbachensis tautavelensis nov. subsp.     

Dental microwear in the orthodentine of the Xenarthra (Mammalia) and its use in reconstructing the palaeodiet of extinct taxa: the case study of Nothrotheriops shastensis (Xenarthra,Tardigrada, Nothrotheriidae)

The utility of orthodentine microwear analysis as a proxy for dietary reconstruction in xenarthrans (tree sloths, armadillos) was quantitatively and statistically accessed via low‐magnification stereomicroscopy. Features such as number of scratches and pits, as well as presence of gouges, hypercoarse scratches, > four large pits, > four cross scratches, and fine, mixed or coarse scratch texture were recorded in 255 teeth from 20 extant xenarthran species. Feature patterns are consistent with scar formation through abrasional (tooth–food) and attritional (tooth–tooth) contact. Number of scratches is the most dietary diagnostic microwear variable for xenarthrans, with herbivorous sloths characterized by > ten scratches and nonherbivorous armadillos by < ten scratches. Discriminant function analysis differentiated arboreal folivores (sloths) and frugivore‐folivores (sloths) both from each other and from fossorial carnivore‐omnivores (armadillos) and insectivores (armadillos). Microwear patterns in carnivore‐omnivores and insectivores are difficult to distinguish between; armadillo microwear may reflect a fossorial lifestyle (grit consumption) rather than primary diet. Cabassous centralis is anomalous in its microwear signal relative to all other insectivores. To test the utility of orthodentine microwear analysis as an indicator of palaeodiet in extinct xenarthrans, microwear in the ground sloth Nothrotheriops shastensis was quantitatively and statistically compared to microwear in extant taxa. Microwear patterns in N. shastensis are most comparable to extant folivores based on scratch number and hierarchical cluster analysis. This strongly supports an herbivorous diet for N. shastensis that is corroborated by multiple independent lines of evidence. Thus, orthodentine microwear analysis can be used to reconstruct diet in extinct xenarthrans. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 201–222.     

Évolution des caractères technologiques et typologiques des industries lithiques dans la stratigraphie de la Caune de l'Arago

The thick Quaternary deposits of the Caune de l’Arago (Pyrénées-Orientales, France) are dated to between 690 000 and 90 000 years old. At least fifteen different archeostratigraphical units have been identified within these deposits, each corresponding to distinct prehistoric occupations. Numerous stone tools made from several different rock types, have been discovered in each unit. The tools present specific characteristics concerning the choice of raw materials, the typology, and the technology used to produce them. Morpho-technological study of the different components of the assemblage contributes to a better understanding of the debitage methods used for their production. Each raw material is considered individually in order to ascertain its origin in the environment, its typological role and the technology applied during its exploitation. Defining production systems leads to the characterisation of the assemblages from each unit. When compared, they reveal common elements, as well as differences, suggesting evolutionary trends. Some observations are also made concerning the extent to which changing uses of the site may have influenced the general morphology of each assemblage, therefore taking into account exterior factors. Analysis of this rich stone tool assemblage helps to situate the Caune de l’Arago industry within the larger evolutionary context of the Lower Paleolithic in Mediterranean Europe.     

Non-occlusal dental microwear variability in a sample of Middle and Late Pleistocene human populations from Europe and the Near East

Non-occlusal, buccal tooth microwear variability has been studied in 68 fossil humans from Europe and the Near East. The microwear patterns observed suggest that a major shift in human dietary habits and food processing techniques might have taken place in the transition from the Middle to the Late Pleistocene populations. Differences in microwear density, average length, and orientation of striations indicate that Middle Pleistocene humans had more abrasive dietary habits than Late Pleistocene populations. Both dietary and cultural factors might be responsible for the differences observed. In addition, the Middle Paleolithic Neanderthal specimens studied show a highly heterogeneous pattern of microwear when compared to the other samples considered, which is inconsistent with a hypothesis of all Neanderthals having a strictly carnivorous diet. The high density of striations observed in the buccal surfaces of several Neanderthal teeth might be indicative of the inclusion of plant foods in their diet. The buccal microwear variability observed in the Neanderthals is compatible with an overall exploitation of both plant and meat foods on the basis of food availability. A preliminary analysis of the relationship between buccal microwear density and climatic conditions prevailing in Europe during the Late Pleistocene has been attempted. Cold climatic conditions, as indicated by oxygen isotope stage data, seem to be responsible for higher densities of microwear features, whereas warmer periods could correspond to a reduced pattern of scratch density. Such a relationship would be indicative of less abrasive dietary habits, perhaps more meat dependent, during warmer periods.     

Non-masticatory uses of anterior teeth of Sima de los Huesos individuals (Sierra de Atapuerca, Spain)

In this study we examine the labial and occlusal surfaces of incisors and canines of hominins recovered from the Sima de los Huesos (SH), middle Pleistocene site, in order to establish the possible extra-masticatory use of anterior teeth. We have compared the microwear of these fossils with microwear from the anterior teeth of Australian Aborigines, a population characterized by ethnographic evidence of the use of their teeth as a third hand. These two samples of teeth were microscopically analyzed using Scanning Electron Microscopy (SEM). Our results support the “cultural” origin of microwear observed on fossil teeth: we conclude that the SH hominins used their anterior teeth as a “third hand” for para- or extra-masticatory activities.     

Seasonal or ecological differences in diet and molar microwear in Cebus nigrivittatus

Dental microwear analyses have raised new hopes and questions for functional morphologists. One hope is that analyses will allow insights into subtle dietary differences of extinct species. One major question is whether seasonal and/or habitat differences in dental microwear are reliably detectable. The extensive collections of Cebus nigrivittatus obtained by the Smithsonian Venezuelan Project allowed us to examine seasonal and habitat differences in dental microwear. Specimens were collected from three distinct ecological life zones that are distinguished by both the amount of rainfall and its seasonability. Environmental variation is generally correlated with variation in resource availability which, in C. nigrivittatus, affects diet. Published field studies indicate that these animals depend more on dry hard fruit and chitinous invertebrates during drier times and succulent fruits and caterpillars during wetter times of the year. As in previous microwear analyses, epoxy replicas were prepared from dental impressions, and the replicas were examined under a scanning electron microscope. Two micrographs were taken of facet 9 on M² of each specimen. Mean values for the proportion of pits (vs. scratches), pit wdith, and scratch width were computed for each of 62 individuals and compared between ecological zones and collecting dates by using a multiple comparison test. Results indicate that, while seasonal differences in molar microwear in C. nigrivittatus are perhaps reliably detectable, 1) they are small in magnitude, 2) they are only detectable in certain ecological life zones, and 3) they are not of the order of magnitude that will obscure major interspecific differences in molar microwear such as those between C. apella and C. nigrivittatus.     

Premiere decouverte en Europe Sud-occidentale de Praeovibos priscus (Mammalia,Artiodactyla, Ovibovinae) dans le gisement pleistocene moyen ante-risseien de la Caune de l'Arago (Tautavel,Pyrenees-Orientales,France)

Teeth, cranial and postcranial skeletton of Praeovibos were sampled from the sediments of the Caune de l'AragoCave. This material is enough to recognize the anatomical relationships between Praeovibos and Ovibos. Praeovibos is discovered for the first time in France and in South Western Europe also. The problem of the correlation of the whole European Middle Pleistocene is approached from a different point of view.     

Seasonal Mortality Patterns in Primates: Implications for the Interpretation of Dental Microwear

The microscopic traces of use wear on teeth have been extensively studied to provide information that will assist in elucidating the dietary habits of extinct hominin species. 1 - 13 It has been amply documented that dental microwear provides information pertaining to diet for living animals, where there is a strong and consistent association between dental microwear patterns and different types of foods that are chewed. The details of occlusal surface wear patterns are capable of distinguishing among diets when the constituent food items differ in their fracture properties. 14 - 20 For example, the microwear traces left on the teeth of mammals that crush hard, brittle foods such as nuts are generally dominated by pits, whereas traces left on the teeth of mammals that shear tough items such as leaves tend to be characterized by scratches. These microwear features result from and thus record actual chewing events. As such, microwear patterns are expected to be variably ephemeral, as individual features are worn away and replaced or overprinted by others as the tooth wears down in subsequent bouts of mastication. Indeed, it has been demonstrated, both in the laboratory and the wild, that short‐term dietary variation can result in the turnover of microwear. 17 , 21 - 23 Because occlusal microwear potentially reflects an individual's diet for a short time (days, weeks, or months, depending on the nature of the foods being masticated), tooth surfaces sampled at different times will display differences that relate to temporal (for example, seasonal) differences in diet. 24     

Habitat et mode de vie des chasseurs paléolithiques de la Caune de l'Arago (600 000-400 000 ans)

Several human occupations have been identified within the deposits of the Caune de l’Arago Cave site, dated from 700 000 years to 100 000 years old. The exceptional wealth of these archeological levels provides an opportunity for the study of different types of habitat and behavioral patterns of Paleolithic hunters between 600 000 and 400 000 years ago. Results from preliminary studies, carried out over the last 30 years on these archeological levels, allow for the proposition of a typology for cave habitats during the Middle Pleistocene in the south of France. In fact, four types of habitat were identified and defined. They have been described according to different characteristics such as, the thickness of the archeological accumulation, the animal species represented, the season during which the animals were hunted, the state of conservation of the fossils discovered, the morpho-technological and typological characteristics of the lithics, the categories of raw materials used and the territory exploited by the hominids inhabiting the cave, as defined by the raw materials represented. The four habitation types defined are: the long duration habitat, where the cave was used as a home base; the temporary seasonal habitat, in which case the cave served as a secondary campsite; the hunting stopover and the bivouac, during which the cave was used as a refuge for short term stays. Behavioral patterns appear to be directly related to the type of habitat and oriented towards a principal activity: hunting. The activities performed by the inhabitants of the cave seem to be more diversified during prolonged or seasonal occupations, whereas they appear to be reduced or very specialised during brief stays. Generally, The characteristics studied show that the Caune de l’Arago Cave site had multiple uses over time for Anteneandertalian family groups and hunters who left traces of their activities, allowing us to better understand their lifestyle.     

Potential Bark and Fruit Browsing as Revealed by Stereomicrowear Analysis of the Peculiar Clawed Herbivores Known as Chalicotheres (Perissodactyla,Chalicotherioidea)

This low magnification stereomicrowear study samples a broad range of chalicotheres (Perissodactyla, Chalicotherioidea), including basal chalicotheres and the two chalicotheriid subfamilies Schizotheriinae and Chalicotheriinae, primarily including species from North America and Europe, but also some from Asia. The schizotheriines Moropus, Tylocephalonyx, and Metaschizotherium and the chalicotheriines Anisodon and Chalicotherium are best represented. Paleodiets are interpreted via discriminant analysis, using comparison of microwear variables from fossil chalicothere teeth with those from a database of extant ungulates with known diets. The results suggest that all of the chalicotheres in the study were browsers, with no evidence of significant grass consumption. Basal chalicotheres, like basal equids, seem to have been standard fruit-dominated browsers. Stereomicrowear agrees with mesowear results by Schulz et al. (2007) and Schulz and Fahlke (2009) for Metaschizotherium bavaricum, Metaschizotherium fraasi, Anisodon grande, and Chalicotherium goldfussi in showing a highly abrasive aspect to the diet. In these species, hard food objects such as fibrous fruits, seeds, pits, and nuts may have abraded the teeth (based on high pit counts, the presence of large puncture pits, and many individuals with coarse to hypercoarse scratches). Anisodon grande and C. goldfussi, despite their relatively short, brachydont teeth, show the highest degree of abrasion within the studied sample. Moropus and Tylocephalonyx from North America show somewhat different but also abrasive microwear; in these taxa the resistant foods may have been twigs and bark (large pits common, but gouging more prevalent than puncture pits). A preliminary comparison of stereomicrowear on DP4, the deciduous upper fourth premolar, with that on molars suggests that juveniles consumed similar foods as adults but without the most abrasive elements. Some important methodological differences regarding the scoring of microwear features by different low-magnification microwear methodologies are discussed.     

Linkages between large‐scale climate patterns and the dynamics of Arctic caribou populations

Recent research has linked climate warming to global declines in caribou and reindeer (both Rangifer tarandus) populations. We hypothesize large‐scale climate patterns are a contributing factor explaining why these declines are not universal. To test our hypothesis for such relationships among Alaska caribou herds, we calculated the population growth rate and percent change of four arctic herds using existing population estimates, and explored associations with indices of the Arctic Oscillation (AO) and the Pacific Decadal Oscillation (PDO). The AO, which more strongly affects eastern Alaska, was negatively associated with the population trends of the Porcupine Caribou Herd and Central Arctic Herd, the easternmost of the herds. We hypothesize that either increased snowfall or suboptimal growing conditions for summer forage plants could explain this negative relationship. Intensity of the PDO, which has greatest effects in western Alaska, was negatively associated with the growth rate of the Teshekpuk Caribou Herd in northwestern Alaska, but the Western Arctic Herd in western Alaska displayed the opposite trend. We suggest that the contrasting patterns of association relate to the spatial variability of the effects of the PDO on western and northwestern Alaska. Although predation and winter range quality have often been considered the primary causes of population variation, our results show that large‐scale climate patterns may play an important role in caribou population dynamics in arctic Alaska. Our findings reveal that climate warming has not acted uniformly to reduce caribou populations globally. Further research should focus on the relative importance of mechanisms by which climate indices influence caribou population dynamics.     

MicroWeaR: A new R package for dental microwear analysis

Mastication of dietary items with different mechanical properties leaves distinctive microscopic marks on the surface of tooth enamel. The inspection of such marks (dental microwear analysis) is informative about the dietary habitus in fossil as well as in modern species. Dental microwear analysis relies on the morphology, abundance, direction, and distribution of these microscopic marks. We present a new freely available software implementation, MicroWeaR, that, compared to traditional dental microwear tools, allows more rapid, observer error free, and inexpensive quantification and classification of all the microscopic marks (also including for the first time different subtypes of scars). Classification parameters and graphical rendering of the output are fully settable by the user. MicroWeaR includes functions to (a) sample the marks, (b) classify features into categories as pits or scratches and then into their respective subcategories (large pits, coarse scratches, etc.), (c) generate an output table with summary information, and (d) obtain a visual surface‐map where marks are highlighted. We provide a tutorial to reproduce the steps required to perform microwear analysis and to test tool functionalities. Then, we present two case studies to illustrate how MicroWeaR works. The first regards a Miocene great ape obtained from through environmental scanning electron microscope, and other a Pleistocene cervid acquired by a stereomicroscope.     

True grit: A microwear experiment

Recently we noted the effects of experimental diets on microscopic dental wear in the American opossum and concluded that it might prove difficult to distinguish the microwear produced by an insectivorous diet from that produced by some kinds of herbivorous ones. We also noted that wear caused by gritty diets and those containing plant opal, although they might be confused with one another, are easily distinguished from other sorts of dietary wear. Our conclusions have been challenged on the basis that possibly we did not allow sufficient time in the experiments for diagnostic wear patterns to emerge. Additional data reported here show that this is not so. Even in our n “control” animals, fed a relatively soft unabrasive diet, enough time elapsed to produce significant dental wear. A new technique is described which for the first time allows the study of changing patterns of microscopic wear in a living animal over a period of time, thus allowing each animal to serve as its own control. A solution containing a broad-spectrum proteolytic enzyme when applied to the teeth of an anesthetized animal removes the proteinaceous coat (pellicle) which will otherwise obscure wear scratches. Precision dental impressions can then be made which reveal the details of the pattern of microwear on the teeth.     

Molar microwear of subfossil lemurs: improving the resolution of dietary inferences

In this study we use molar microwear analyses to examine the trophic distinctions among various taxa of Malagasy subfossil lemurs. High resolution casts of the teeth of Megaladapis, Archaeolemur, Palaeopropithecus, Babakotia, and Hadropithecus were examined under a scanning electron microscope. Megaladapis was undoubtedly a browsing folivore, but there are significant differences between species of this genus. However, dietary specialists appear to be the exception; for example, Palaeopropithecus and Babakotia probably supplemented their leaf-eating with substantial amounts of seed-predation, much like modern indrids. Hadropithecus was decidedly not like the modern gelada baboon, but probably did feed on hard objects. Evidence from microwear and coprolites suggests that Archaeolemur probably had an eclectic diet that differed regionally and perhaps seasonally. Substantial trophic diversity within Madgascar's primate community was diminished by the late Quaternary extinctions of the large-bodied species (>9 kg).     

牙齿微痕研究在古食性重建中应用的简述

在古食性研究中,牙齿微痕是指动物在咀嚼食物的过程中在牙齿咬合面上产生的微观磨损痕迹。不同食性的动物具有不同的牙齿微痕特征,因此可以通过研究牙齿微痕特征来重建灭绝动物的古食性,为探讨动物演化和古生态环境变化提供重要信息。本文主要介绍牙齿微痕作为一种简单而高效的古食性重建方法在古生物领域中的应用。本文主要内容包括牙齿微痕的发展历史,形成机理与应用,以及近年来被广泛应用的牙齿微痕定量化分析——表面纹理分析法,并在最后浅谈了牙齿微痕研究未来可能研究的方向。     

Anterior dental microwear and its relationship to diet and feeding behavior in three african primates (Pan troglodytes troglodytes,Gorilla gorilla gorilla andPapio hamadryas)

Anterior dental microwear is shown to be related to diet and to feeding habits in three groups of extant African primates includingPan troglodytes troglodytes, Gorilla gorilla gorilla andPapio hamadryas. Five distinct types of incisal microwear are found in these groups. These include: fine wear striae, polish, small pits, large pits and microflakes. It is demonstrated that each species exhibits a different set of microwear types. Chimpanzees exhibit extensive pitting, mesiodistally oriented fine wear striae and small areas of polish, features of microwear that are probably related to the husking of hard fruit skins and the occasional stripping of leaves. Gorillas show large areas of polish, small pits and labiolingually oriented wear striae, a combination of features that may be associated with the stripping of leaves and pith. Baboons show extensive edge damage involving clusters of large pits and microflakes; this set of microwear types may be related to the initial chewing of gravel-laden seeds, roots and rhizomes. Microwear found on the canine/premolar complex of all three groups corresponds to the puncture-crushing and to the slicing of food.     

Simulation of dental microwear: Characteristic traces by opal phytoliths give clues to ancient human dietary behavior

In order to further evaluate the process of microwear formation on human dental enamel, microwear was experimentally produced by a chewing simulation with an Academic Center for Dentistry Amsterdam (ACTA) device. For this simulation, several cereal species were processed according to historical milling techniques, the experimental results of which were compared with those obtained from cereals processed after modern techniques, and also with natural microwear on early medieval human molars. Comparison of simulated microwear pits with natural microwear pits showed that the simulation led to traces which matched those found on the historical teeth in terms of both size and shape. Experimentally produced microwear pits were especially characteristic for the cereal species used in the simulations, and both pit morphology and enamel loss were a function of cereal phytolith content. Despite the high variability of phytolith size and shape, certain types are characteristic for certain cereals, which in turn are capable of producing cereal-specific microwear. This experimental approach is likely to further define ancient human dietary behavior, including food processing.     

Technical note: An in vitro study of dental microwear formation using the BITE Master II chewing machine

Dental microwear has been used for decades to reconstruct the diets of fossil hominins and bioarchaeological populations. The basic theory has been that hard‐brittle foods (e.g., nuts, bone) require crushing and leave pits as they are pressed between opposing cheek‐tooth surfaces, whereas soft‐tough foods (e.g., grass blades, meat) require shearing and leave scratches as they are dragged along opposing surfaces that slide past one another. However, recent studies have called into question the efficacy of microwear as an indicator of diet. One issue has been the limited number of in vitro studies providing empirical evidence for associations between microwear pattern and chewing behavior. We here describe a new study using a chewing simulator, the BITE Master II, to examine the effects of angle of approach between opposing teeth and food consistency on microwear surface texture. Results indicate that opposing teeth that approach one another: 1) perpendicular to the occlusal plane (crushing) result in pits; 2) parallel to the occlusal plane (shearing) result in striations in the direction of movement; and 3) oblique to the occlusal plane (45°) result in both striations and pits. Results further suggest that different food types and abrasive loads affect the propensity to accumulate microwear features independent of feature shapes. Am J Phys Anthropol 158:769–775, 2015. © 2015 Wiley Periodicals, Inc.