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1

A new method for live-trapping shrews

100%

Hays W. S. T.

Acta Theriologica

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1998

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tom 43

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nr 3

A modification of the Sherman trap, intended for live-trapping of shrews (Soricidae), is presented. This trap requires only daily checks, in contrast to the two- to four-hourly checks required by other traps. A population study using the new trap design yielded 711 captures over 7 520 trap-days, with 1% mortality.

2

A morphometric study of the amygdala in the common shrew

88%

Rowniak M., Szteyn S., Robak A.

Folia Morphologica

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2004

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tom 63

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nr 4

The characteristic features of the common shrew amygdala (CA), as shown by volumetric comparisons of the individual nuclei, are the poor development of the lateral (LA) and basomedial (BM) nuclei as well as the particularly strong formation of the basolateral (BL) and lateral olfactory tract (NLOT) nuclei. The central (CE), cortical (CO) and medial (ME) nuclei are also well organised in this species. All these features are even more distinctly visible when the total number of neurons in the nuclei referred to are compared. A comparison of the densities of neurons in the individual nuclei with the mean numerical density of cells in the CA indicates that there are the 3 different regions within the common shrew’s CA. The densities of neurons in the LA, BL, and BM are significantly lower than the mean density of cells in the CA (p < 0.05). In the CE this value does not differ from the mean (p > 0.05). In the CO, ME and NLOT the density values are significantly higher than the mean (p < 0.05). Furthermore, a similar division of the shrew’s CA can, to some extent, be performed using the size parameters of the amygdaloid neurons as a marker. Interestingly, the large neurons populate less densely organised CA areas like the LA, BL and BM, whereas the small cells populate the ME and NLOT, where the neurons are densely arranged. The CE and CO occupy intermediate positions, with the neurons similar in size to the mean for the shrew’s CA.

3

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Fine structure of the infective eggs of the dilepidid cestode Hepatocestus hepaticus [Baer, 1932], a parasite of shrew

75%

Swiderski Z., Tkach V. V.

Wiadomości Parazytologiczne

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1998

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tom 44

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nr 3

4

Species richness relative abundances and habitat use in local assemblages of Sorex shrews in Eurasian boreal forests

75%

Sheftel B. I., Hanski I.

Acta Theriologica. Supplement

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2002

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tom 47

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nr 1

Using a large body of observational data on the occurrence of Sorex shrews in boreal forests, we test two models that predict the structure of small mammal communities along a gradient of increasing habitat productivity. Tilman's (1982) model predicts a humped curve of species richness along productivity gradients. In contrast, we found a linear increase in species richness with increasing logarithm of the pooled density of shrews, which we use as a measure of habitat productivity for shrews. The model of Hanski and Kaikusalo (1989) assumes a trade-off between exploitative and interference competitive abilities, and it predicts that the size structure of small mammal communities should shift from the dominance of small species (superior in exploitative competition) in unproductive habitats to the dominance of large species (superior in interference competition) in productive habitats. Shrew assemblages show such a shift. Though it is not possible to draw definite conclusions about the role of interspecific competition from our observational data, the changing size structure of local shrew assemblages with increasing habitat productivity is a predictable feature of their community structure.

5

The karyotype of the Azumi shrew Sorex hosonoi

75%

Moribe J., Noro T., Kobayashi S., Oda S.

Acta Theriologica

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2007

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tom 52

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nr 1

Karyotype ofSorex hosonoi Imaizumi, 1954 from Mt. Asama in central Honshu, Japan, were examined with conventional staining and G-banding using ASG methods. The diploid and fundamental autosomal arm numbers were 42 and 66, respectively. The autosomes consisted of seven metacentric, six submetacentric, and seven acrocentric pairs. The sex chromosomes were large-sized acrocentric X and small-sized subtelocentric Y. The relationship between the karyotypes ofS. hosonoi andS. shinto was explained by one pericentric inversion at the no. 5 ofS. hosonoi and the no. 9 ofS. shinto. A rearrangement inS. shinto-hosonoi differed from the rearrangements occurring on no. 5 ofS. shinto-caecutiens/unguiculatus.

6

Cases of coat colour anomalies in the common shrew, Sorex araneus L.

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Chetnicki W., Fedyk S., Bajkowska U.

Folia Biologica

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2007

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tom 55

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nr 1-2

7

Factors affecting the distribution of Sorex samniticus, an endemic Italian shrew, in an heterogeneous landscape

75%

Mortelliti A., Amori G., Sammuri G., Boitani L.

Acta Theriologica

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2007

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tom 52

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nr 1

We studied the factors affecting the distribution of an endemic shrewSorex samniticus Altobello, 1926 in the Province of Siena, central Italy. Distribution data were obtained by examining pellets from 31 barn owlTyto alba sites (roosts) over a period spanning from 1974 to 2005. We constructed a model using logistic regression analysis on presence/absence data. Results show that an increase in forest dominated byQuercus cerris andCastanea sativa led to the local extinction of this species. Results were confirmed through the examination of one box, with 3044 prey items deposited in layers, that documents the expansion of the species in that area following increased logging ofQuercus cerris andCastanea sativa forests. Cessation of logging has again led to the absence of the species from the area. We discuss these results from the perspective of ecological network planning, showing that utilisation of non-detailed maps, such as Corine Land Cover, that do not distinguish between the various kind of broadleaved forests is inadequate to describe the finer grade of habitat selection of this small mammal.

8

Loss of the third upper premolar in Suncus murinus and its relation to jaw size

75%

Natori M., Shigehara N.

Acta Theriologica

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1997

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tom 42

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nr 1

Musk shrew Suncus murinus (Linnaeus, 1766) has a very reduced P3, and it is often missing. Hanamura (1985), based on a sample from Okinawa Island, proposed that the high incidence in P3 loss was a distinguishing characteristic of musk shrew. However, while the Okinawa population lacked P3 in 26 of 95 individuals (27.4%), specimens from Taiwan showed no P3 loss. Thus, the high incidence of P3 loss is not one of distinguishing characteristic of musk shrews. In the Okinawa sample, P4-M3 length vs palatal length in the group with P3 on both sides was significantly greater than that without P3. The relationship between the P4-M3 and palatal lengths showed negative allometry (Okinawa population with P3: y = 0.18 + 0.67a:; Okinawa population without P3: y = 0.21 + 0.67x; Taiwan population: y = 0.15 + 0.68x). Taiwan population had a greater P4-M3 length relative to palatal length than did the Okinawa population because palatal length was greater in the former. These findings suggest that, as in the case of human third molars, a reduction in upper jaw size is responsible for the loss of the third molar in the Okinawa musk shrews.

9

Seasonal pelage variation in the masked shrew Sorex cinereus: a demographic perspective

75%

Rinehart-Whitt S. C., Pagels J. F.

Acta Theriologica

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2000

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tom 45

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nr 1

Pelage characteristics of the masked shrew Sorex cinereus Kerr, 1792, were studied with emphasis on season, age and gender to determine the relationship of fur to life history characteristics. A total of 140 shrews was collected from 1985-1989 at five montane sites in Virginia. Hair length (mm) and hair density (no. of hairs/mg fat-free skin) were measured to identify the extent of pelage variation. Shrews caught in winter had significantly longer (4.4 mm) and more dense (8100 hairs/mg) hair than shrews caught in summer (3.6 mm and 7767 hairs/mg, respectively). Age class had a significant effect on hair density in summer; immature shrews (age class I) had the greatest median hair densities (7985 hairs/mg) of any age class. Old adults (age class IV) had the lowest hair density during both summer and winter, possibly reflecting an old-age molt. Females had significantly higher hair densities (8301 hairs/mg) than males (7509 hairs/mg) during summer. Due to the lower energy costs of morphological adjustments compared to physiological changes, alteration of pelage in S. cinereus may be an important mechanism to decrease total energy demands as has been described in many other small mammals.

10

Phenotypic diversity and population dynamics: another look (with particular reference to the common shrew Sorex araneus)

75%

Zakharov V. M., Pankakoski E., Sheftel B. I.

Acta Theriologica. Supplement

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1997

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nr 04

We studied temporal changes in the level of phenotypic diversity, measured by the total phenotypic variance for several characters of skull morphology, in two populations of the common shrew Sore:e araneus Linnaeus, 1758. We compared a population from central Siberia having a high-amplitude four-year cycle with a population from southern Finland having noncyclic dynamics. The level of total phenotypic diversity varied significantly among years in both populations, but was correlated neither with density nor with breeding success in either of them. We did, however, find differences between the two populations. When we compared changes in the level of phenotypic diversity with changes in the level of developmental stability, as measured by chance developmental variance (fluctuating asymmetry), the cyclic Siberian population exhibited increased developmental variability in the peak year, which was associated with relatively small proportion of other sources of variation (and genetic variation in particular). In other years, the role of chance variation was less and the proportion of other sources of variance was higher. On the other hand, in the noncyclic Finnish population, oscillations in the level of phenotypic diversity were mainly caused by changes in developmental stability. These results illustrate that not only dynamics of genotype variety, but also the alterations in the level of developmental stability can be of great importance for changes in phenotypic diversity.

11

Differences in abundance and species richness between shrews and rodents along an elevational gradient in the Udzungwa Mountains, Tanzania

75%

Stanley W. T., Hutterer R.

Acta Theriologica

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2007

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tom 52

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nr 3

Small mammals (shrews and rodents) were surveyed along an elevational transect in the Udzungwa Scarp Forest Reserve, in the Udzungwa Mountains, Tanzania. Trap lines and pitfall lines were installed at 600, 910, 1460, and 2000 m a.s.l. In a total of 10341 sample nights (7448 trap-nights and 2893 bucket-nights) 343 specimens (148 shrews, 205 rodents) were captured representing 9 shrew and 14 rodent species for a total of 23 species. While overall species diversity generally increased with elevation, this pattern was not constant for each group sampled. For rodents, both species richness and abundance were lowest at 600 m and greatest at 2000 m a.s.l., and were significantly correlated with elevation. While the highest species number and abundance for shrews was at 2000 m, there was no correlation of these two values with elevation. Rainfall appears to have affected the capture of shrews, but not rodents, and capture success of individual buckets and traps indicated a lack of capture independence. Eastern Arc endemics such asCrocidura desperata Hutterer, Jenkins and Verheyen, 1991 andMyosorex kihaulei Stanley and Hutterer, 2000 were more abundant at 2000 m a.s.l., than at lower elevations. Implications of results of this survey for analyses of future biotic surveys are discussed.

12

Why are shrews so small? The costs and benefits of small size in Northern temperate Sorex species in the context of foraging habits and prey supply

75%

Churchfield S.

Acta Theriologica. Supplement

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2002

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tom 47

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nr 1

This paper reviews the ecological advantages and disadvantages of very small body size in Sorex Linnaeus, 1758 shrews living at high latitudes with cold winters. It examines the feeding and foraging habits of small and large shrews in the context of prey supply, location of winter prey sources, territory requirements, habitat exploitation and inter-specific competition. Data on feeding habits and prey availability show that the major costs of small size are a reduction in food niche breadth and prey biomass resulting from restrictions on the type and size of prey eaten, and large territory requirements. Major benefits of small size are the ability to subsist on small, numerous and accessible arthropods with high encounter rates, enabling coexistence with larger congeners and exploitation of low-productivity habitats less suitable for larger earthworm-eating species. Small size, coupled with low per capita food intake, is shown to be of special adaptive value in cold winters when food supply is restricted mostly to small arthropods, and earthworms are few.

13

Note on the systematic status of shrews of the Sorex araneus group in NW Anatolia

75%

Macholan M., Filippucci M. G., Slivkova L., Simson S.

Acta Theriologica

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1999

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tom 44

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nr 1

Macholan M., Filippucci M. G., Slivkova L. and Simson S. 1999. Note on the systematic status of shrews of the Sorex araneus group in NW Anatolia. Acta Theriologica 44: 101-106. Although it was assumed that the northern parts of Asia Minor were occupied by the Caucasian shrew, Sorex satunini, some recent findings have cast doubts on the specific status of shrew populations in NW Anatolia. Here, a single shrew from Uludag was studied using enzyme electrophoresis. It was compared to S. araneus from Europe and S. satunini from NE Turkey as well. The results unequivocally classify the animal under study with S. satunini and it is suggested that the common shrew, S. araneus, does not occur either in NW Anatolia or in Asia Minor in general.

14

Molecular phylogeny of Crocidura shrews in Northeastern Asia: A special reference to specimens on Cheju Island, South Korea

75%

Han S. H., Iwasa M. A., Ohdachi S. D., Oh H. S., Suzuki H., Tsuchiya K., Abe H.

Acta Theriologica

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2002

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tom 47

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nr 4

Molecular phylogeny of crocidurine shrews (Insectivora, Soricidae) in northeastern Asia was investigated to confirm the taxonomic status of unidentified specimens of Crocidura from Cheju Island, South Korea. Phylogenetic trees were constructed by neighbor-joining (NJ) and maximum likelihood (ML) methods, based on mitochondrial cytochrome b gene sequences (402 base pairs) of 37 individuals of seven crocidurine species and three unidentified specimens from 31 localities mainly in northeastern Asia. Phylogenetic position of the three unidentified specimens from Cheju Island were compared with those of Suncus murinus, C. attenuata, C. dsinezumi, C. lasiura, C. sibirica, C. suaveolens, and C. watasei. Both in NJ and ML trees, the three unidentified specimens were included in the cluster of C. dsinezumi and were obviously different from C. suaveolens on Cheju Island. Thus, the present investigation demonstrated that both C. suaveolens and C. dsinezumi exist on Cheju Island.

15

Metric discrimination and distribution of the species of Crocidura occuring in Tunisia

75%

Sara M., Zanca L.

Acta Theriologica

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1992

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tom 37

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nr 1-2

A recent paper on the occurrence of the genus Crocidura in Tunisia reports a single specimen identified as C. suaveolens. Therefore a third species, besides C. russula and C. whitakeri would occur in the country. However, the presence of C. suaveolens in North-Africa is controversial and was recently ruled out from the other Maghrebi countries (Algieria and Morocco). During the period 1989 - 90, 71 specimens of shrews were collected from owls pellets or trapped at Tunisian 12 sites. This material was measured and studied both by classic morphometric and multivariate methods (Fuzzy test, Principal Coordinate Analysis and Generalized Procrustes Analysis), considering also reference samples (C. suaveolens from Italy and Balearic Islands, C. russula and C. whitakeri from Morocco). Four of the 12 trapped shrews were karyotyped and resulted to have a C. russula karyotype, some differences in biometry as well as in Number of Fundamental arms (NFa) separate the Moroccan population from the Tunisian one and raise some interesting questions on the taxonomy of C. russula. Multivariate analysis also allowed us to exclude the presence of C. suaveolens from the Tunisian material studied and suggested also the misclassification of the proposed specimen that should be reconsidered as C. whitakeri. A preliminar distribution map of the two species living in Tunisia was drawn, also based on the scanty data from the literature.

16

Habitat preferences of four sympatric species of shrews

75%

Rychlik L.

Acta Theriologica. Supplement

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2000

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tom 45

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nr 1

17

Comparative genome mapping in mammals: the shrew map

75%

Larkin D. M., Serov O. L., Borodin P. M., Zhdanova N. S., Searle J. B.

Acta Theriologica. Supplement

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2000

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tom 45

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nr 1

18

Fostering in southern African Soricidae

75%

Baxter R. M.

Acta Theriologica

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1993

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tom 38

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nr 4

The successful raising one young of one female Crocidura f. flavescens by another is reported. Attempts at using C. h. hirta and Myosorex varius as foster parents, and as well as at hand rearing of C. f. flavescens were unsuccessful. An attempt is made to explain the significance of this occurrence.

19

Comparing life histories of shrews and rodents

75%

Gliwicz J., Taylor J. R. E.

Acta Theriologica. Supplement

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2002

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tom 47

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nr 1

Small insectivores and rodents, despite similarities in body size and attributes scaling to body size, exhibit significant differences in other properties, including many life history traits. In this article major differences between life history traits of the two taxa are reviewed, with an indication of contrasting selection pressures related to somewhat different body size, as well as to differences in metabolic rates, diet and exposure to predation. Additionally, since the life history differences between small mammals are particularly well pronounced in highly seasonal habitats, the winter ecology of shrews and rodents is compared. Finally, the two different reproductive strategies typical for soricine shrews and small nonhibernating rodents, are presented. In conclusion, it is proposed that the reproduction delayed to the second calendar year of life in shrews is the result of selection for traits ensuring successful survival in winter, a period that is more perilous for shrews than for rodents. In rodents, in contrast, opportunistic reproduction is the most prominent characteristic which also helps to maximize their reproductive output. This ability for high reproduction seems to be the main antipredatory measure selected for in rodent evolution.

20

Home ranges of sympatric soricine shrews in Hokkaido, Japan

75%

Ohdachi S.

Acta Theriologica

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1992

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tom 37

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nr 1-2

Home ranges of sympatric shrews, Sorex unguiculatus Dobson, 1890 S. gracillimus Thomas, 1907 and S. caecutiens Thomas, 1907 were studied by a mark-recepture method during the non-snow covered seasons in northern Hokkaido, 1988 and 1989. Home range size of S. unguiculatus, the largest species (15.1 g for adult males), was not significantly different from that of S. gracillimus, the smallest species (4.4 g for adult males). Both S. unguiculatus and S. gracillimus had more exclusive home ranges within species than between species. Tolerance of home range overlap may be related to the reduction of dietary overlap. No reliable information of home range for S. caecutiens was obtained in this study.

Ograniczanie wyników

A new method for live-trapping shrews

A morphometric study of the amygdala in the common shrew

Fine structure of the infective eggs of the dilepidid cestode Hepatocestus hepaticus [Baer, 1932], a parasite of shrew

Species richness relative abundances and habitat use in local assemblages of Sorex shrews in Eurasian boreal forests

The karyotype of the Azumi shrew Sorex hosonoi

Cases of coat colour anomalies in the common shrew, Sorex araneus L.

Factors affecting the distribution of Sorex samniticus, an endemic Italian shrew, in an heterogeneous landscape

Loss of the third upper premolar in Suncus murinus and its relation to jaw size

Seasonal pelage variation in the masked shrew Sorex cinereus: a demographic perspective