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A new arrangement for keeping moles in captivity was designed by combining newly conceived units and different types of structures previously described by other authors. The structure is especially devoted to long term studies, such as those on activity patterns and reproductive and social behaviours. A simple and economic system for automatic recording of activity rhythms in moles is also presented and discussed.
The present studies were carried out on the brains of the adult mole and rabbit. The preparations were made by means of the Golgi technique and the Nissl method. Two types of neurons were distinguished in the preoptic area (POA) of both species: bipolar and multipolar. The bipolar neurons have oval, fusiform or round perikarya and two dendritic trunks arising from the opposite poles of the cell body. The dendrites bifurcate once or twice. The dendritic branches have swellings, single spine-like and filiform processes. The multipolar neurons usually have triangular and quadrangular perikarya and from 3 to 5 dendritic trunks. The dendrites of the mole neurons branch sparsely, whereas the dendrites of the rabbit neurons display 2 or 3 divisions. On the dendritic branches varicosities and different protuberances were observed. The general morphology of the bipolar and multipolar neurons is similar in the mammals studied, although the neurons of the rabbit POA display a more complicated structure. Their dendritic branches show more divisions and possess more swellings and different processes than the dendrites of the neurons of the mole POA. Furthermore, of the multipolar neurons only the dendrites in POA of the rabbit were observed to have a rosary-like beaded appearance.
Density was estimated for three populations of eastern moles Scalopus aquaticus Linnaeus, 1758, in South Carolina using a trapping grid and assessment lines. As­sessment line data were based upon the repair of holes punched into surface tunnels of the animals. Using a new method of analysis for assessment line data, a logistic curve was fitted to the data. Density estimates based upon these analyses were (95% confidence intervals in parentheses) 3.02 (1.90 - 4.98), 2.73 (1.48 - 12.52), and 1.71 (0.86 - 2.69) moles/ha. In previous studies using assessment line data to estimate density, obtaining confidence intervals for the density estimate presented theoretical problems. In this study, Monte Carlo procedures were used to obtain an estimate of the approximate 95% confidence intervals for density. The analytical methods used in the present study eliminate the concepts of boundary strip width (strict sense) and the occurrence of distinctive zones with constant capture probabilities, and as such, represent important conceptual improvements of the assessment line density estima­tion method.
The generic attribution of the Plio-Pleistocene Polish moles ?Neurotrichus polonicus and ?Neurotrichus skoczeni has been questioned several times in the past. The fossil material belonging to ?Neurotrichus polonicus and ?Neurotrichus skoczeni is re-evaluated here and a new diagnosis is provided on the basis of qualitative considerations. In addition, a Geometric Morphometric analysis of the humerus has been performed including both extant and extinct Neurotrichini and Urotrichini taxa for comparison. Our results proved the unique morphology of the Polish material suggesting a distinct taxonomic state. The morphological variations evidenced by the humeral shape analysis agree with the observed qualitative differences and support a new generic allocation. The new genus Rzebikia gen. nov. is proposed for all the material previoulsly ascribed to ?Neurotrichus polonicus and ?Neurotrichus skoczeni.
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The moles from the South German fissure fillings Petersbuch 6, 10, 18, 31, 35, 48 include 14 species, four of which are new: Leptoscaptor bavaricum gen. et sp. nov., Leptoscaptor robustior gen. et sp. nov., Myxomygale gracilis sp. nov. and Tenuibrachiatum storchi gen. et sp. nov. Most samples are characterised by their high species diversity. Talpa minuta is the most common species in nearly all samples. Leptoscaptor is characterised by a slender humerus and by the loss of lower antemolars. It is interpreted as a Miocene offshoot of the Scalopini. Myxomygale gracilis represents the latest record of the genus. Tenuibrachiatum storchi has a slender humerus and one lower incisor is lost. The species is structurally ancestral to the extant Urotrichus. The genus Pseudoparatalpa Lopatin, 1999 is considered a synonym of Paratalpa. The talpids of the Petersbuch fissures are in line with a Middle Miocene correlation of MN 7+8 as already indicated by the cricetids. The remains of desmans in the Petersbuch 6 fissure filling indicate the proximity of water. The presence of Urotrichini in nearly all samples, albeit scanty, suggests a forestal environment within the range of the owls, which preyed on them.
Trichuris feliui sp. nov. from the common mole, Talpa europaea (L., 1758), in Spain is described. The new species differs from other Trichuris spp. cited in Soricomorpha. From T. busuluk Polozhentsev, 1935 and T. mettami (Baylis, 1935), T. feliui sp. nov. differs in the morphology of the vulvar region, the spicule tip, the terminal position of the anus in females of T. busuluk, and in metrical features (body length, maximal body width, oesophagus length, ratios of forebody to hindbody length, spicule length and width, width of spicule at the proximal end, length of spicular sheath, egg length and width). The species most similar to T. feliui is T. neomi. The presence of a vulvar appendage in females, two postcloacal papillae in males and the absence of a spicular tube in T. feliui, separate this species from T. neomi. Measurements of body length, maximal body width, oesophagus length, spicule length, spicule width, and spicule width at the proximal end are additional characters that distinguish the two species. From T. muris Schrank, 1788 and T. arvicolae Feliu et al., 2000 found in small mammals in the same site, T. feliui differs in metrical characters. Also, the vulvar appendage is absent in T. muris and T. arvicolae and the spicular tube is present in both species. The presence of T. feliui in T. europaea is discussed from the perspective of helminthological and biogeographical aspects of Talpa spp. and other Soricomorpha.
Dental anomalies in the Japanese mole, Mogera wogura Temminck, 1842, from northeast China and the Primorsky region of Russia were examined based on 241 specimens. The most frequent dental anomaly was oligodonty, i.e., missing P2 (18 cases) or P3 (one case). Supernumerary teeth were observed in three cases, two of which were characterized by abnormal shapes. Morphological abnormalities in teeth (six cases) and an asymmetrically curved rostrum (one case) were also observed. Dental anomalies were found at higher frequencies in populations near the northern range limit of the species. This was not caused by size effects. We suggest that the high incidence of dental anomalies was the result of genetic drift, which increases in marginal populations. Considering the nature of subterranean mammals, our results suggest that the high frequency of dental anomalies in a marginal population could have initiated the evolution of dental formulae if parapatric or peripatric speciation occurs in such populations.
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