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1

An osteometric study on recent roe deer [Capreolus capreolus L., 1758]

100%
Wustinger J., Galli J., Rozpedek W.
Folia Morphologica
|
2005
|
tom 64
|
nr 2
97-100
The analysis of the data shows that the growth of roe deer from the eastern part of Greater Poland (Wielkopolska) is very similar to that of specimens from other areas in Poland. A comparison with excavated bone material revealed only slight and fluctuating differences. The roe deer from the areas to the west of Poland are larger and those from the areas to the east of the country are the largest.
2

Craniometric study of the common shrew (Sorex araneus L. 1758) from different localities and chromosomal races across Germany and Europe

75%
Stefen C.
Acta Theriologica
|
2013
|
tom 58
|
nr 3
A total of 440 skulls of common shrews, Sorex araneus, from Germany and Europe (Croatia, Hungary, Austria, and Norway) were studied. The material represented six chromosomal races (Ulm, Laska, Drnholec, Mooswald, Jütland, and Abisko) assignable to the Western European and Northern European karyotypic groups. The race of a few samples was not determined. Twenty-one linear measurements were taken on skulls and mandibles and used in this study. Pearson correlations and multiple linear regressions were used to see the relationship of the cranial variables to altitude, latitude, the chromosomal race, and the geographic location. The results from the tested samples differed; the most negative correlations to latitude were found in the samples assigned to the Western European karyotypic group (WEK), the least negative ones in the samples of the Ulm race. These results indicate the converse of Bergmann's rule. But taking into consideration all the samples of the different karyotypic groups across Europe, the correlations to latitude included positive ones, which would indicate that Sorex follows Bergmann's rule in some of the variables. The studied material of different karyotypic groups could not be differentiated in discriminant analyses. The separation of the studied races within the WEK alone was slightly better, but about 30 % of ungrouped cases remained. Only the separation of the regional samples within one chromosomal race revealed better results but was still very different between the races. This indicates that within the races, regional differences might be strong enough for a separation of the samples and that within a karyotypic group, and even more so across karyotypic groups, regional differences conceal racial differences.
3

Cervus canadensis and C. elaphus: North American subspecies and evaluation of clinal extremes

75%
Schonewald C.
Acta Theriologica
|
1994
|
tom 39
|
nr 4
The distinctiveness of each extant North American subspecies of C. elaphus (Linnaeus, 1758) was tested using craniometric data. To provide a context for interpretation of these data, the distinctiveness of North American C. elaphus from Eurasian C. elaphus was reassessed from existing data and conclusions tested. Mor­phometry variations in size, shape, and sexual dimorphism of adult crania were analyzed using combined male-female and independent male and female principal component analyses. North American subspecies do not represent natural biogeogra- phic variation as earlier presumed. Posterior classification error was highest for subspecies, but was lowest for a set of 6 Operational Taxonomic Units that recognized C. elaphus-Olympic, C. e/apftus-northern California and Oregon, C. claphus-eastern Washington, C. elaphus-Rocky mountain and Cascade mountain, C, elaphus-Sas- katchewan and Manitoba, and C. elaphus-centra\ California. Males and females differed in their sizes, shapes and affinities to other populations. Intracontinental differences in the kind and amount of sexual dimorphism reinforced the importance of measuring and contrasting male and female features in phylogeographic analyses. Use of existing nomenclature as a blind guide for comparative systematica and ecology and for conservation undermines the quality of research and conservation for C. ela­phus in North America. Previous arguments for a single-species circumgiobal cline do not take into account sexual dimorphism, behavior and reproduction. Major interconti­nental differences do exist between clinal extremes in behavior, in cranial size and sexual dimorphism in addition to semilethal Fi hybridization. All suggest C. elaphus and North American Cervus are different species. Whether the transition is smooth, whether stepped transitions occur, and whether "canadensis" correctly represents the species' distribution need verification.
4

Craniometrical characteristics of wolves Canis lupus from Poland

75%
Okarma H., Buchalczyk T.
Acta Theriologica
|
1993
|
tom 38
|
nr 3
Skulls of 145 adult wolves Canis lupus Linnaeus, 1758 from two areas of the highest wolf density in Poland (78 from the Carpathian Mountains and 71 from the Białowieża Primeval Forest) were measured using 17 selected characters. Values of cranial characters measured were similar to those of previous studies from mid- dleastern Eurasia. Generally, wolf skulls were larger in the mountain than in the lowland population; males from the Carpathian Mountains were larger than that from the Białowieża Forest, however females were slightly smaller than that in the Biało­wieża Forest. On both areas males were larger than females, but a difference between sexes was much highly pronounced in wolves from the mountain population.
5

Craniometrics of the orange mouse opossum Marmosa xerophila [Didelphimorphia: Didelphidae] in Venezuela

75%
Lopez-Fuster M. J., Salazar M., Perez-Hernandez R., Ventura J.
Acta Theriologica
|
2002
|
tom 47
|
nr 2
Skull size variation in the orange mouse opossum Marmosa xerophila Handley and Gordon, 1979 in Venezuela was analysed by sex and geographic location. Morphometric relationships between the species and the closely related M. robinsoni Bangs, 1898 were also studied. Results showed that M. xerophila is a sexually dimorphic and geo­graphically homogeneous species. Males had larger skulls than females, although dimorphism was mainly related to length, height, and some dental parameters. Inter­specific comparisons revealed that M. xerophila has a smaller skull than M. robinsoni, even in the sympatric area where the smallest specimens of M. robinsoni occur. Dis­criminant function analyses between these species, for males and females separately, provided accurate classification functions that allowed correct specific determination. In Venezuela, M. xerophila lives in arid lands with xerophilous thorny woodland and scrub, up to 90 m above see level.
6

Missing data in craniometrics: a simulation study

75%
Gauthier O., Landry P. A., Lapointe F. J.
Acta Theriologica
|
2003
|
tom 48
|
nr 1
Craniometric measurements represent a useful tool for studying the differentiation of mammal populations. However, the fragility of skulls often leads to incomplete data matrices. Damaged specimens or incomplete sets of measurements are usually discarded prior to statistical analysis. We assessed the performance of two strategies that avoid elimination of observations: (1) pairwise deletion of missing cells, and (2) estimation of missing data using available measurements. The effect of these distinct approaches on the computation of inter-individual distances and population differentiation analyses were evaluated using craniometric measurements obtained from insular populations of deer mice Peromyscus maniculatus (Wagner, 1845). In our simulations, Euclidean dis­tances were greatly altered by pairwise deletion, whereas Gower's distance coefficient corrected for missing data provided accurate results. Among the different estimation methods compared in this paper, the regression-based approximations weighted by coefficients of determination (r2) outperformed the competing approaches. We further show that incomplete sets of craniometric measurements can be used to compute distance matrices, provided that an appropriate coefficient is selected. However, the application of estimation procedures provides a flexible approach that allows researchers to analyse incomplete data sets.
7

Systema platinum axiale in mammals. Part IV. A. Artiodactyla. Fetal period

63%
Pedziwiatr Z. F.
Folia Morphologica
|
1990
|
tom 49
|
nr 3-4
8

Craniometrical characteristics and dental anomalies in wolves Canis lupus from Latvia

63%
Andersone Z., Ozolins J.
Acta Theriologica
|
2000
|
tom 45
|
nr 4
A total of 187 skulls (115 adult males and 72 adult females) of the wolf Canis lupus Linnaeus, 1758 hunted in Latvia between 1975-1999 were measured, using 19 cranio­metrical parameters. General cranial characteristics were similar to those described from the wolf populations of Belarus and Poland (the difference was not statistically significant). Sexual dimorphism in skull size was determined. Most of the skull para­meters from north and east Latvia appeared to be slightly larger than those from the Kurland Peninsula, being isolated by large cities, rivers and deforested lands. Also, anomalies in tooth formula were described. Deviations from the normal tooth pattern were found in 9.5% skulls. Congenital oligodonty and polydonty was found in 7.9% skulls. Polydonty was observed in 71.4% cases of tooth anomalies. Tooth anomalies were more common in males than in females.
9

A case of pseudohermaphroditism in a male of European roe deer [Capreolus capreolus L.]

63%
Kubacki T., Wajdzik M.
Forestry
|
2002
|
tom 05
10

Sexual dimorphism in size of the skull of Spanish ibex Capra pyrenaica

63%
Fandos P., Vigal C. R.
Acta Theriologica
|
1993
|
tom 38
|
nr 1
Sexual dimorphism in the skull of Spanish ibex Capra pyrenaica Schinz, 1838 is analyzed by means of univariate and multivariate techniques in one of the most representative populations of the species, located in the Sierra de Gredos, central Spain. Thirty eight measurements were used for the analysis: 30 of the skull and mandible, and 8 of the horn. Eighty three skulls (40 males and 43 females) of individuals older than 4 years were used. In 36 out of the 38 variables males were significantly larger than females. Horn characters showed the highest variability and also the most significant differences between sexes. Values of Mahalanobis distance between males and females were high (D2 = 323.1). When Factor Analysis is performed with the whole set of 38 variables, 7 Principal Factors were extracted, scores of Principal Factor 2 (related with horn variables) and Principal Factor 3 {related to molar toothrow length) showing significant differences between sexes. In this analysis, horn characters (Principal Factor 2) accumulate the sexual dimorphism of other skull traits. However, if the same analysis is performed without horn characters, 5 Principal Factors were extracted, scores of three Principal Factors showing significant differ­ences between sexes. Highest sexual dimorphism in this analysis corresponds to the Principal Factor 3 (molar toothrow), follow the Principal Factor 2 (posterior region of the skull) and Principal Factor 1 (main length measurements). This suggest that the high degree of sexual dimorphism observed in the Spanish ibex skull is mainly related to horn traits and, to a lesser extent, of other skull features like molar toothrow length.
11

Morphology and morphometry of the nuchal plane of breeding chinchilla [Chinchilla laniger, Molina 1782] skulls allowing for sex and litter size at birth

51%
Baranowski P., Wroblewska M., Wojtas J.
Bulletin of the Veterinary Institute in Puławy
|
2009
|
tom 53
|
nr 2
291-298
The aim of the investigation was to determine the effect of sex and litter size at birth on the values of selected metric traits of breeding chinchilla skulls. Eighty-six chinchillas of both sexes, aged 12 months, kept under similar nutrition and care conditions, were used in the study. The skull's weight was determined, as well as 14 craniometrical traits of the braincase and the splanchnocranium. The volume of the rteurocranium and the area of the foramen magnum surface were determined, and the cranial index was estimated. The basic statistical measurements and the simple, parietal, and semi-parietal correlations between selected traits of the nuchal plane were estimated. The sex and litter size at birth were not the source for variations in the traits: A-P, B-P, A-N, N-P, Zyg- Zyg, Eu-Eu. A significant effect (P≤0.01) of sex of the chinchilla on the height of the squama occipitael bone and the foramen magnum index was found. The inherence of the statistical significance in parietal and semi-parietal correlations for the selected nuchal plane of the skull confirms the necessity of making allowances for sex in craniometric research, as well as for litter size at birth in the case of estimating the values of the metric traits in the skulls of animals coming from multiple litters.
12

Allometric analysis of cranial parameters of American mink, including bones of masticatory apparatus

51%
Jakubowski H., Komosa M., Frackowiak H.
Electronic Journal of Polish Agricultural Universities. Series Veterinary Medicine
|
2008
|
tom 11
|
nr 3
13

Morphological analysis and morphometry of the foramen magnum of the American Staffordshire terrier breed newborns

51%
Chroszcz A., Janeczek M., Wojnar M., Pospieszny N.
Medycyna Weterynaryjna
|
2006
|
tom 62
|
nr 09
1002-1004
The aim of the investigations was the description of foramen magnum morphology. Fourteen skulls of American Staffordshire terrier pups were examined. The morphology of the foramen magnum was described, its height and width were measured, and the index of the foramen magnum (width/height × 100) was calculated. The height of the skull, maximum width and maximum height of the occipital condyle were also measured. In all the examined skulls the shape of the foramen magnum was regular and ellipsoidal. The average height of the foramen magnum was 5.7 mm, the average width - 6.05 mm. The value of the foramen magnum index was 106.82. The average skull height was 22 mm. The average maximum height of the occipital condyle was 5.33 mm and its average maximum width was 2.85 mm. There were no differences between females and males in all parameters. The shape of the foramen magnum was regular. The occipital condyli were symmetrical.
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