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31.
Mitochondrial phylogeography of the edible dormouse (Glis glis) in the western Palearctic region
Helene Hürner, Boris Kryštufek, Maurizio Sará, Alexis Ribas, Tanja Ruch, R. Sommer, Victoria Ivashkina, Jochan R. Michaux, 2010, izvirni znanstveni članek

Opis: This study describes in detail the phylogeographic pattern of the edible dormouse (Glis glis) a European rodent with pronounced hibernating behavior. We used sequences of 831 base pairs of the mitochondrial DNA cytochrome-b gene from 130 edible dormice collected at 43 localities throughout its distribution. Our results reveal presence of 3 main haplogroups: Sicilian, South Italian (restricted to the Calabrian region), and European (a widespread lineage corresponding to all remaining western, central, and eastern European populations). Examination of paleontological data confirms refugial regions for G. glis in the 3 Mediterranean peninsulas, although overall low genetic diversity is found. The low diversity of the European lineage is probably the result of a recent expansion (dated around 2,000 years ago) from a single refugium. Other factors, such as the ecological constraints on the species, may have caused genetic bottlenecks that reinforced the low genetic variability of G. glis. This work could have important implications for strategies to conserve the edible dormouse by defining important areas for their conservation.
Najdeno v: osebi
Ključne besede: dormouse, Glis-glis, glacial refugia, mitochondrial DNA, phylogeography, Europe
Objavljeno: 15.10.2013; Ogledov: 1515; Prenosov: 55
URL Polno besedilo (0,00 KB)

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Species richness and distribution of non-volant small mammals along an elevational gradient on a Mediterranean mountain
Boris Kryštufek, Nataša Režek Donev, Janko Skok, 2011, izvirni znanstveni članek

Opis: We explored the alpha and gamma patterns in species richness of non-volant small mammals on Mt. Snežnik (sea level: 1796 m) on the northern edge of the Mediterranean Basin. A total of 2871 individuals were sampled belonging to 23 different species of rodents and soricomorphs. Two estimates of true species richness (sample-based rarefaction and abundance-based coverage estimator of species richness, ACE) yielded very similar values to empirical data. The empirical number of species varied between 4 and 11 per station in alpha-richness and between 5 and 17 per 200 m elevational interval in gamma-richness. The 95% confidence intervals for ACE overlapped between elevations in both data sets, hence not a single sampling site or elevational interval emerged statistically richest or poorest in the number of species. The two patterns responded to elevation in a very different way but any of the curves was decidedly humped. The mid-domain effect predictions failed to reproduce the pattern of observed or estimated species richness, and hence the ranges were located non-randomly along the elevational gradient. The pattern of distribution and diversity is supposedly generated by the environmental variables correlated to the elevation, which vary in a non-random manner with elevation
Najdeno v: osebi
Objavljeno: 15.10.2013; Ogledov: 1759; Prenosov: 41
URL Polno besedilo (0,00 KB)

34.
Unusual occurrence of the bicoloured white-toothed shrew (Crocidura leucodon)
Boris Kryštufek, 2009, kratki znanstveni prispevek

Najdeno v: osebi
Ključne besede: Crocidura leucodon, habitat selection, altitudinal distribution, Slovenia, South Europe
Objavljeno: 15.10.2013; Ogledov: 2972; Prenosov: 26
URL Polno besedilo (0,00 KB)

35.
Mitochondrial cytochrome b sequences resolve the taxonomy of field mice (Apodemus) in the western Balkan refugium
Boris Kryštufek, Martina Lužnik, Elena Bužan, 2012, izvirni znanstveni članek

Opis: Apodemus sylvaticus stankovici, described from the topographically rough landscape of the western Balkan glacial refugium, was recently proposed as being either a junior synonym of Apodemus flavicollis or a species on its own right. To untangle this taxonomic vagueness, we sequenced complete cytochrome b gene in 28 field mice collected at 12 locations in the mountains of Bosnia and Herzegovina, Montenegro, western Macedonia and northern Greece. Samples yielded 27 new haplotypes which clustered into two distinct groups. One of these clades also included the reference haplotype of A. flavicollis, while another cluster emerged as being identical with the reference sample for A. sylvaticus. As is common in Apodemus, both species retrieved in our analysis were characterized by low levels of intraspecific variation (0.4- 0.9%) as opposed to a high level of differentiation between them (8.0-10.0%); therefore, the taxonomic classification of our material was without doubt. We found no evidence regarding the presence of an additional cryptic species in the mountains of the western Balkans. The very similar values of genetic variability in the two species imply their common evolutionary history of a long-term coexistence in the western Balkan refugium
Najdeno v: osebi
Ključne besede: Mice, Apodemus flavicollis, Apodemus sylvaticus, Apodemus stankovici, molecular taxonomy
Objavljeno: 15.10.2013; Ogledov: 2375; Prenosov: 56
URL Polno besedilo (0,00 KB)

36.
The status of a rare phylogeographic lineage of the vulnerable European souslik Spermophilus citellus, endemic to central Macedonia
Boris Kryštufek, Peter Glasnović, Svetozar Petkovski, 2012, kratki znanstveni prispevek

Opis: The conversion of grasslands for agriculture has triggered a serious decline of the European ground squirrel or souslik Spermophilus citellus, categorized as Vulnerable on the IUCN Red List since 1996. The Jakupica phylogeographic lineage of central Macedonia is the smallest of the three major evolutionary lines of the European souslik. This lineage is an important reservoir of within-species diversity and should be regarded as an independent unit for conservation management purposes. It is endemic to Mount Jakupica, where it lives in mountain pastures at 1,500-2,250m altitude. The total area occupied by sousliks (884 ha) is fragmented and 94% of individuals occur in four colonies. Densities (0.8-5.5 adults ha-1) are lower than those reported elsewhere for the species, with the total population probably ,2,000 adults. One large colony, reportedly of c. 1,000 sousliks, was decimated in 2007 by a catastrophic fire and had still not recovered bz 2010. A steady decline in livestock grazing, together with the predicted advance of the tree line as a consequence of climate change, will probably reduce the optimal habitat for the souslik and negatively affect population fitness. Monitoring needs to be implemented, at least for the largest colonies, to provide early warning of any declines
Najdeno v: osebi
Ključne besede: Spermophilus citellus, souslik, European souslik, density, endemic, distance sampling, fragmentation, Macedonia
Objavljeno: 15.10.2013; Ogledov: 2129; Prenosov: 48
URL Polno besedilo (0,00 KB)

37.
Female reproductive characteristics of the Horvath's rock lizard (Iberolacerta horvathi) from Slovenia
Katarina Ljubisavljević, Peter Glasnović, Katja Kalan, Boris Kryštufek, 2012, izvirni znanstveni članek

Opis: In this paper, we present data on the female reproductive traits of the Horvath's rock lizard from Slovenia. The clutch, egg and hatchling characteristics were investigated based on clutches laid in laboratory conditions by pregnant females collected from a natural population. A female lays one clutch of eggs annually with an average number of three (range 1-5) eggs. We found a significant positive correlation between female size and egg width and volume. The mean egg length and volume in a clutch decreased significantly with clutch size independently of female size. The incubation period averaged 44 days. Significant positive correlations were found between the hatchling total length and mass, and egg mass. There was a significant negative relationship between the egg mass and incubation duration. The life-history strategy of the Horvath's rock lizard appeared to be shaped by several factors, such as the constraints of a high-altitude environment, flattened body morphology and possibly phylogenetic background
Najdeno v: osebi
Ključne besede: Horvatova kuščarica, Iberolacerta horvathi, kuščarice, življenjski ciklus
Objavljeno: 15.10.2013; Ogledov: 1719; Prenosov: 33
URL Polno besedilo (0,00 KB)

38.
Population genetics of chamois in the contact zone between the Alps and the Dinaric Mountains
Elena Bužan, Josef Bryja, Barbora Zemanová, Boris Kryštufek, 2013, izvirni znanstveni članek

Opis: The chamois is a habitat specialist ungulate occupying continental archipelagos of fragmented rocky habitats which are frequently restricted to high altitudes. It is not clear whether forest habitats separating such population fragments act as barriers to gene flow. We studied the genetic makeup of the chamois in a topographically diverse landscape at the contact zone of two mountain ranges in Slovenia. Based on sequences of mitochondrial DNA, all Slovenian populations belong to a Northern chamois (Rupicapra r. rupicapra) subspecies. The range of chamois in Slovenia encompasses three different regions, each with unique topography, habitat connectivity and abundance of chamois: the Alps, the Dinaric Mts., and the Pohorje Mts. The habitat of the chamois is extensive and more or less continuous in the Alps, but suboptimal and fragmented in the remaining regions. In agreement with neutral genetic theory, large Northern chamois populations tended to have higher allelic richness and observed heterozygosity. Spatial clustering bears the differentiation into four geographically associated clusters within Slovenia and also revealed a strong substructure within all mountain ranges with suboptimal chamois habitat. Surprisingly, some small Dinaric populations have stayed genetically isolated in restricted habitat patches, even if they are geographically very close to each other. The four clusters, each having a unique demographic history, should be regarded as independent units for management purposes.
Najdeno v: osebi
Ključne besede: Rupicapra rupicapra, Chamois, population structure, microsatellites, fragmentation, conservation management
Objavljeno: 15.10.2013; Ogledov: 1968; Prenosov: 29
URL Polno besedilo (0,00 KB)

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Evolutionary history of mole rats (genus Nannospalax) inferred from mitochondrial cytochrome b sequence
Boris Kryštufek, Elena Ivanitskaya, Atilla Arslan, Emine Arslan, Elena Bužan, 2012, izvirni znanstveni članek

Opis: Mole rats (genus Nannospalax) display prolific chromosomal variation with more than 50 distinct cytotypes. These cytotypes are largely indistinguishable morphologically, are mainly allopatric and their taxonomic ranking is contradictory. We established a cytochrome b phylogeny for 15 cytotypes belonging to all three species recognized on morphological grounds (morphospecies): N. leucodon, N. xanthodon and N. ehrenbergi. Phylogenetic reconstructions yielded two highly divergent groups which are in agreement with the current division into two subgenera (Nannospalax and Mesospalax). The former comprised samples from south-eastern Turkey, Israel and Egypt (the morphospecies N. ehrenbergi). Basal dichotomy within Mesospalax remained unresolved and the putative sister position of N. leucodon against the two lineages of N. xanthodon was not supported in our analysis. Net divergences between sister cytotypes were low (< 2.0%) and two N. leucodon cytotypes were not even reciprocally monophyletic. Among the three morphospecies, the genetic diversity was lowest in N. leucodon (2.4% 0.3%), highest in N. xanthodon (8.8% 0.7%) and intermediate in N. ehrenbergi (5.0% 0.5%). Our results show that associations between genetic and chromosomal variation are not widespread and common in mole rats, and therefore refute the generalization of a 'cytotype-equals-species' approach
Najdeno v: osebi
Ključne besede: molecular phylogeny, Nannospalax ehrenbergi, Nannospalax leucodon, Nannospalax xanthodon, Spalax, species delimitation
Objavljeno: 15.10.2013; Ogledov: 1766; Prenosov: 67
URL Polno besedilo (0,00 KB)

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