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181.
Evaluating the genetic status of a closed colony of titi monkeys (Callicebus cupreus) using multigenerational pedigrees 下载免费PDF全文
Pedigree metrics are essential for investigating colony genetic structure. The genetic structure of a closed Callicebus cupreus colony was examined using multigenerational pedigrees. Inbreeding was low, but genetic drift caused the loss of founder genome representation. Pedigrees can be used to detect founder representation and prevent bottlenecks and allele loss. 相似文献
182.
Pollen records of Holocene sediment cores from the Costa Rican Cordillera de Talamanca (La Chonta bog, 2310 m and La Trinidad bog, 2700 m) show the postglacial development of the montane oak forest zone from ca. 9500 to 1500 yr BP. During the early Holocene (ca. 9500–700 yr BP), alder vegetation covered the La Chonta and La Trinidad bogs and their adjacent hills. The upper forest line is inferred to be at 2800–3000 m elevation. A Podocarpus-Quercus forest characterised the middle Holocene (ca. 7000–4500 yr BP). The upper forest line is located at >3000 m reaching the present-day altitudinal distribution. A Quercus forest characterised the late Holocene (ca. 4500–1500 yr BP). Compared to modern conditions, the early Holocene has similar average temperatures, but the moisture level was probably higher. Pollen evidence for the late Holocene indicates drier environmental conditions than today. In order to improve the paleoecological interpretation, we described the local vegetation and used moss samples as pollen traps at both montane bogs along strong soil moisture gradients.The Netherlands Centre for Geo-ecological Research, ICG 相似文献
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R. E. Price P. T. Tinkey N. E. Leeds J. D. Hazle L. A. Langford L. C. Stephens K. K. Ang 《Journal of medical primatology》1996,25(2):140-145
Abstract: An adult female rhesus monkey that had received 44.0 Gy of cobalt 60 radiation to 8 cm of the cervical and upper thoracic spinal cord approximately 2.8 years postirradiation developed a sudden onset of self-mutilation and loss of function of the right arm followed progressively by loss of function of the left arm and terminally bilateral paresis of the legs. Histopathologic examination of the cervical spinal cord revealed a glioblastoma multiforme that extended from the cervical medullary junction to the sixth cervical vertebrae. Because of the infrequent occurrence of spontaneous neoplasia in rhesus monkeys and the location in the radiation field, the glioblastoma is believed to be radiation induced. 相似文献
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MICHAEL A. SCHILLACI LISA JONES-ENGEL BENJAMIN P. Y.-H. LEE AGUSTIN FUENTES NANTIYA AGGIMARANGSEE GREGORY A. ENGEL TULYAWAT SUTTHIPAT 《Biological journal of the Linnean Society. Linnean Society of London》2007,92(4):675-694
Crab-eating, or long-tailed, macaques [ Macaca fascicularis (Raffles, 1821)] have been studied extensively throughout their distribution in South and South-east Asia. Despite this extensive body of research, the island population of long-tailed macaques from Singapore remains virtually undescribed. In the present study, we compare the morphometric variability and patterns of growth observed in a population sample from Singapore with a composite sample from Thailand, north of the Isthmus of Kra. The results of our analyses indicate that there are statistically significant differences between the two populations in adult size and shape. For both males and females, the Singapore population is smaller than the Thai population. Relative to body length, the Singapore macaques exhibit significantly longer tails, and, relative to cranial length, they exhibit significantly more narrow faces than the Thai macaques. Although levels of sexual dimorphism for most morphometric traits are very similar, indicating similar levels of male–male competition for females, the Singapore males exhibit a significantly larger testicular volume relative to body weight, suggestive of an alternative male reproductive strategy. In addition to adult somatometric size and shape, comparisons of growth patterns relative to age and body size reveal significant differences between the two population samples. Combined, these results suggest either that statistically significant differences in adult morphology and patterns of growth can occur in presumably reproductively cohesive subspecies, or the Singapore macaques may be taxonomically distinct. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 675–694. 相似文献
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Thousands of vertebrate fossils have been recovered from the lower Omo River Valley, in southern Ethiopia, however, fishes have been poorly reported. Here we describe fossil fish remains deriving from the Shungura Formation, part of the Omo Group of deposits ranging in date from 1.8 to 3.4 my. Two new species are reported, Sindacharax omoensis (Characiformes) and Lates arambourgi (Perciformes), which suggest greater diversity of these genera than previously documented. 相似文献
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An experiment was designed to test the response of the nasal cavity and associated structures to maxillary deformity. Forty young M. mulatta were surgically produced in 20 animals, and the small maxillary segments moved medialward. Intrapair observation tests were applied to selected measurements and indices of symmetry relationships. Deformity of the surgically undisturbed nasal septum occurred in response to the maxillary deformation. The lateral walls were moved medially with the maxilla, but in six months symmetry relationships were similar to those found in the control animals. The lateral walls of the nasal cavity appeared to be relatively independent of the shape and position of the tooth carrying part of the maxilla. The development and use of primate models can contribute to understanding the extent of the adaptational response systems in facial morphogenesis. 相似文献
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A new fossil brachypterous psocid tax on belonging to the family Trogiidae is characterized, illustrated and described from the early Eocene Fushun amber. Paralepinotus fushunensis nov. gen., nov. sp., shares several characters with the genus Lepinotus von Heyden, 1850, but differs from it mainly by the presence of tibial spurs other than apical ones and the absence of a forked sensillum on the last maxillary palp. This fossil taxon is also characterized by relatively developed elytriform forewing but still not reaching the tip of the abdomen. A checklist of all known Trogiidae is provided. 相似文献