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The caudal intercarotid artery was investigated in 6 species of Equidae family and in lowland tapir of Tapiridae family. It was found that this artery connects bilateral intracranial segments of the internal carotid artery. It is located in the cavernous and intercavernous sinuses, caudal to the hypophysis. This artery being constant vessel in horse, is also permanent vessel in other species of Equidae family. It is homologous with anastomising vessel in fishes, amphibia, reptiles and birds.
Sexual dimorphism is reviewed and described in adult skulls of Chilotherium wimani from the Linxia Basin. Via the analysis and comparison, several very significant sexually dimorphic features are recognized. Tusks (i2), symphysis and occipital surface are larger in males. Sexual dimorphism in the mandible is significant. The anterior mandibular morphology is more sexually dimorphic than the posterior part. The most clearly dimorphic character is i2 length, and this is consistent with intrasexual competition where males invest large amounts of energy jousting with each other. The molar length, the height and the area of the occipital surface are correlated with body mass, and body mass sexual dimorphism is compared. Society behavior and paleoecology of C. wimani are different from most extinct or extant rhinos. M/F ratio indicates that the mortality of young males is higher than females. According to the suite of dimorphic features of the skull of C. wimani, the tentative sex discriminant functions are set up in order to identify the gender of the skulls.
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Tapirs from the Pleistocene of Venezuela

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The living tapir Tapirus terrestrisis widely distributed in Venezuela, occurring mainly south of the Orinoco, while being absent from arid, high Andean and insular areas. Here, we describe new material of fossil tapirs from two Pleistocene localities of Venezuela: Zumbador Cave and El Breal de Orocual. Based on its size and morphology, the material from Zumbador Cave (skull, mandible and postcrania) is assigned to the extant T. terrestris, and represents the most northwestern fossil record of this species in South America. By contrast, the remains from the tar seep of El Breal de Orocual are more gracile, and differ from T. terrestris and other fossil and living species from South America in the presence of a metastylid on the lower cheek teeth. We tentatively assign the latter remains to Tapirussp., based on juvenile and isolated dentary material. However, the possibility that these specimens may represent a new species or an immigrant from North America cannot be completely excluded.
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Here we describe the first record of a chalicothere from the Miocene of Myanmar. The chalicothere, documented by a partial mandible, was unearthed from the lower portion of the Irrawaddy Formation in the region of Magway, Central Myanmar. The Burmese material belongs to an early late Miocene fauna which recently yielded hominoid remains attributed to Khoratpithecus. The specimen, which is attributed to a chalicotheriine, does not reliably match with any described Miocene Eurasian species of this subfamily, suggesting the possibility it belongs to a new taxon. The discovery of a chalicotheriine in the surroundings of Magway contributes to the hypothesis that closed habitats were an important component of the paleoenvironment of Khoratpithecus.
Fossil remains of South American tapirs are often fragmentary and scarce compared with those of other mammals that entered South America during the “Great American Biotic Interchange”. Here, we review and add to the Pleistocene tapir remains from the Tarija Valley (Bolivia), and provide a taxonomic re-evaluation of Tapirus tarijensis. T. tarijensis was a large-sized animal, approximating the size of the living Malaysian T. indicus and the extinct North American T. haysii. The geographical distribution of Pleistocene records of Tapirus in South America indicates that T. tarijensis was the only known species inhabiting the Tarija Valley during this time.
Four different Hunter−Schreger Band (HSB) configurations were observed in the teeth of fossil and extant Perissodactyla. This variability exceeds that observed in Artiodactyla or Proboscidea. The four HSB configurations represent two different evolutionary pathways. Transverse HSB found in many mammalian taxa outside the Perissodactyla represents the most primitive HSB configuration. It occurs in several primitive perissodactyl families and is retained in Palaeotheriidae and extant Equidae. Curved HSB evolved from transverse HSB and occurs in Tapiridae, Helaletidae, and Lophiodontidae, as well as in Ancylopoda and Titanotheriomorpha. This likely indicates independent evolution of curved HSB in two or more lineages, but the number of instances of parallelism of this configuration is obscured by uncertainty in the relationships among these taxa and by a lack of data for some important basal taxa. A second evolutionary pathway leads from transverse HSB via compound HSB to vertical HSB. Compound HSB were detected in Hyrachyidae, Deperetellidae, and the early rhinocerotid Uintaceras. Vertical HSB configuration characterizes the molar dentition of other Rhinocerotidae, Hyracodontidae, Indricotheriidae, and Amynodontidae. Often, the incisors of rhinocerotids retain traces of compound HSB. Thus the HSB configuration reflects phylogenetic relationships to some degree. The selective value of the modified HSB configurations is interpreted functionally as a mechanism to reduce abrasion during mastication, assuming that the perpendicular intersection of prisms with the actual grinding surfaces resists wear better than prisms running parallel to the occlusal surface.
Early Eocene mammals from Indo−Pakistan have only recently come under study. Here we describe the first tapiromorph perissodactyls from the subcontinent. Gandheralophus minor gen. et sp. nov. and G. robustus sp. nov. are two species of Isectolophidae differing in size and in reduction of the anterior dentition. Gandheralophus is probably derived from a primitive isectolophid such as Orientolophus hengdongensis from the earliest Eocene of China, and may be part of a South Asian lineage that also contains Karagalax from the middle Eocene of Pakistan. Two specimens are referred to a new, unnamed species of Lophialetidae. Finally, a highly diagnostic M3 and a molar fragment are described as the new eomoropid chalicothere Litolophus ghazijensissp. nov. The perissodactyls described here, in contrast to most other mammalian groups published from the early Eocene of Indo−Pakistan, are most closely related to forms known from East and Central Asia, where Eocene tapiromorphs are diverse and biochronologically important. Our results therefore allow the first biochronological correlation between early Eocene mammal faunas in Indo−Pakistan and the rest of Asia. We suggest that the upper Ghazij Formation of Pakistan is best correlated with the middle or late part of the Bumbanian Asian Land Mammal Age, while the Kuldana and Subathu Formations of Pakistan and India are best correlated with the Arshantan Asian Land Mammal Age.
Collecting over the last twenty years in sand and gravel quarries near Yulafli in European Turkey has yielded a substantial fauna of large mammals. The most significant of these for biochronology are well−preserved remains of the ursid Indarctos arctoides, the suid Hippopotamodon antiquus, and several rhino genera. They point to a late Vallesian (MN 10−equivalent) age. Several other taxa, of longer chronological range, are in good agreement with this dating. The Proboscidea include, besides the Eastern Mediterranean Choerolophodon, the Deinotherium + Tetralophodon association, commonly found in Europe, and the rare “Mastodon” grandincisivus, here reported for the first time in the Vallesian. The age of Yulafli shows that the large size of some taxa, such as Deinotherium (size close to that of D. gigantissimum) and Dorcatherium, does not always track chronology. The Yulafli fauna is close in composition and ecology to other localities in Turkish Thrace, and also shares several taxa unknown in Anatolia, especially Dorcatherium, with the North−Western European Province. It reflects a forested/humid landscape that extended in Vallesian times along the Aegean coast of Turkey, perhaps as far South as Crete, quite distinct from the open environments recorded at the same period in Greek Macedonia and Anatolia, and probably more like the central European one. Together with the establishment of a Tethys–Paratethys marine connection, this “Eastern Aegean Province” likely acted as an ecological barrier that hindered East−West migrations of open−country large mammals, such as bovids or long−limbed giraffes, and might have contributed to the differentiation of Ouranopithecus and Ankarapithecus.
Based on protein polymorphism and results obtained with RAPD-PCR and ISSR-PCR methods, the domestic and wild Artiodactyla and Perissodactyla (14 and 7 species, respectively) were compared. The marker-specific species differentiation in domestic and wild species was observed, leading to the hypothesis of the “subgenome” existing in domestic species. It is assumed that “subgenome” contains certain genes encoding important proteins and enzymes. In the past, the high variation of “subgenome” could play an essential role in domestication, leading to the wide morphological differentiation of contemporary domestic species.
At the Zoological Garden in Poznań, Poland, 66 stool specimens from animals belonging to 40 species of 4 orders (Primates, Proboscidea, Perissodactyla and Artiodactyla) were examined for Cryptosporidium oocysts. Cryptosporidium oocysts were found in 7 of 66 faecal samples (9.1%) obtained from 6 different animal species. This is the first report of C. parvum in a lesser slow loris, white rhinoceros, Indian elephant and Thorold’s deer. The remaining Cryptosporidium-positive faecal specimens were collected from Japanese macaque and Eld’s deer.
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