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The climatic cooling that began in the late middle Eocene and culminated in the Eocene-Oligocene transition meant major changes in Palaeotheriidae (Perissodactyla, Mammalia) biodiversity in Europe and could have caused the appearance of new dietary strategies. This work is the first to study the spatiotemporal response of one palaeotheriid genus (Plagiolophus) to the Eocene environmental and ecological changes using three dietary proxies: hypsodonty, mesowear and dental microwear texture analysis (DMTA). DMTA is applied for the first time to palaeotheriids. The high diversity and wide chrono-spatial distribution of Plagiolophus make it possible to evaluate spatiotemporal environmental variations, including palaeodiet. We study five Plagiolophus samples from late middle Eocene to early Oligocene from western Iberia to central Europe in order to (1) infer lifetime palaeodiet; (2) infer short-term palaeodiet; and (3) test temporal and spatial trends. All samples present an exclusion of abrasive foodstuff given low hypsodonty index; dominance of browsing given the low mesowear score; and browsing of tough foliage and exclusion of hard items in their diet given DMTA information. These factors point to Plagiolophus as a highly selective feeder that fed on plants with the same features irrespective of chronology or location: tough foliage (leaves from monocots or dicots) avoiding lignified or hard materials, without seasonal variations. • Palaeotheriid dietary strategies changes related with climatic cooling are hypothesized. • Dental hypsodonty, mesowear and microwear are analysed in the Palaeogene Plagiolophus. • Lifetime and short-term palaeodiet and a spatiotemporal trend are studied. • First time Dental Microwear Textural Analysis is applied to palaeotheriids. • Plagiolophus was a highly selective browser-like feeder despite chronology or location. [ABSTRACT FROM AUTHOR]

This study was designed to correlate the dental microwear pattern in a population of roe deer (Capreolus capreolus) with seasonal dietary data. Fifty roe deer specimens from the Chizé Forest in western France provides the material of this study. The shearing facet of the second molars is digitized using a 256 level gray scale light stereomicroscope equipped with a CCD camera. Numbers and dimensions of scratches and pits are quantified using a semi-automatic protocol. Considering the population as a whole, the results are consistent with previous dental microwear analysis and suggest a browsing diet (sensu lato). In fact, the percentage of pits exceeds 50%, which is correlated with a browsing and not grazing. Furthermore, the dental microwear excludes foraging on tubers or roots. Although no significant differences are found between sexes, males from the autumn sample have a higher number of scratches on the shearing molar facets than the females. This may be correlated with the more important intake of fruits by males than females during the rutting period. The number of scratches also suggests a dietary difference between two seasonal clusters. Summer and autumnal samples have a higher frequency of highly scratched dental facets that correlate with the fruit consumption by the roe deer during these periods. Fewer dental pits were found in the roe deer sampled during summer and spring than during the other seasons. This suggests seasonal diet shifts among plant life forms with consumption of soft green leaves during the spring and summer. In winter and autumn, the roe deer feeds often on dead leaves, acorns and ivy. These food items are often consumed with sand or bark particles during the prehension of the food, this would increase the likelihood of more pits than would occur with soft semi-ligneous leaves. This seasonal dental microwear pattern has revealed a relationship between seasonal food availability and deer diets. The dental microwear analysis on this population of roe deer will help determine the paleodietary patterns of extinct ungulates. [Copyright &y& Elsevier]

There are clues that calcium (Ca) isotope composition of vertebrate bioapatite is influenced by diet and trophic level. These clues however conflict with several cases of mammal species exhibiting Ca isotope compositions which are inconsistent with their trophic levels. These observations support that diet may not be the only factor driving the Ca isotope composition in mammalian enamel and bone. To investigate this question, we selected a modern Cervus elaphus population (Bauges Natural Regional Park, Alps, France) to serve as a model for Ca isotope physiology of cervids and other mammals. Subsequently, we reinvestigated the case of the fossil Rangifer tarandus population from Jaurens (Late Pleistocene locality, 32.6 to 29.7 kyr BP, France), a population for which abnormal 44Ca-depleted isotope compositions (regarding the low trophic level of reindeers) have been previously documented. By combining bone samplings and serial enamel micro-samplings, we discuss the main potential sources of Ca isotopic variability in bioapatite of young and adult individuals. This includes the effects of gestation, lactation, antlerogenesis, browser-grazer ecologies, osteophagia and natural mineral licks. Our results suggest an important effect of lactation on bone Ca isotope composition (δ44/42Ca = +0.19 ± 0.09‰; 95% confidence interval), whereas other factors such as gestation or antlerogenesis seem more secondary. Our enamel micro sampling method allowed to detect when enamel Ca isotope composition could be affected by milk consumption or mineral supplementation. Thanks to these advances, we collected new data from the Pleistocene reindeers of Jaurens, which are now consistent with their known low trophic level and plant-based diet. This demonstrates that disentangling ecological and physiological signals within enamel Ca isotope compositions is possible by using serial micro-sampling. This approach allows retrieving accurate trophic information from this proxy and truly pushes forward the limits of Ca isotope applications regarding paleoecology, physiology and ethology. • A lactation signal is preserved in bone Ca isotope composition of female red deer. • Antlers display a different Ca isotope composition than the rest of the skeleton. • Enamel Ca isotope composition changes at the time when cervids are weaned. • Enamel serial micro-sampling allow to untangle dietary signals from other factors. [ABSTRACT FROM AUTHOR]

During the late Miocene Vallesian–Turolian transition, an important faunal turnover affected continental vertebrate faunas, and particularly primates with the replacement of hominids by cercopithecid monkeys in Europe. In order to better understand this turnover from a climatic perspective, stable oxygen and carbon isotope compositions of fossil equid tooth enamel contemporaneous with either hominids or cercopithecids have been analyzed. Hipparion teeth recovered from seven Greek localities spanning from the late Vallesian to the end of Turolian have δ18Op values of apatite phosphate suggesting an increase in mean air temperatures from 13±3°C at the beginning of the Vallesian to 17±2°C during the late Turolian. δ13C values of local plants have been estimated using the carbon isotope compositions of apatite carbonate. By applying to our data the relationship established between the δ13C value of modern C3 plants and mean annual precipitations, estimated average precipitations slightly decreased from 890 (+109 −100) mma−1 to 471 (+58 −54) mma−1 during this time span. According to Köppen's classification of climates, northern Greece was submitted to modern-like Mediterranean climates during the late Miocene. The change in climatic conditions, which took place during the late Vallesian–early Turolian transition, remained within the range of Mediterranean climate modes, thus being unlikely at the origin of a dramatic modification in local vegetation. This study strongly suggests that climate might not be the key factor of the Vallesian–Turolian major faunal turnover at least in the Eastern Mediterranean Basin. [ABSTRACT FROM AUTHOR]

Abstract: A hominid upper premolar was discovered in the Azmaka quarry, near Chirpan (Bulgaria). The associated fauna, especially the co-occurrence of Choerolophodon and Anancus among the proboscideans, and Cremohipparion matthewi and Hippotherium brachypus among the hipparions, constrains the age of the locality to the second half of the middle Turolian (ca. 7 Ma), making it the latest pre-human hominid of continental Europe and Asia Minor. The available morphological and metric data are more similar to those of Ouranopithecus from the Vallesian of Greece than to those of the early to middle Turolian hominids of Turkey and Georgia, but the time gap speaks against a direct phyletic link, and Turolian migration from the east cannot be rejected. [Copyright &y& Elsevier]