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1

Wplyw barier genetycznych i srodowiskowych oraz czynnikow historycznych na przeplyw genow i strukture populacji u zwierzat

100%
Ratkiewicz M.
Kosmos
|
2006
|
tom 55
|
nr 2-3
165-176
2

Od genetyki do genomiki populacji: nowe perspektywy badan w ekologii i biologii ewolucyjnej

100%
Ratkiewicz M.
Kosmos
|
2006
|
tom 55
|
nr 1
129-136
3

Funkcjonowanie populacji łosia w Polsce

63%
Raczynski J., Ratkiewicz M.
Annals of Warsaw University of Life Sciences - SGGW. Animal Science
|
2011
|
tom 50
The natural range of the moose, Alces alces in Europe had been reduced during historical times and the species became extinct in western Europe. In Poland, being the edge of the species' natural range the moose population survived in the wild. After the Second World War, the moose was critically endangered in Poland. Fortunately, its number considerably increased, most probably due to immigration of large numbers of individuals from the former Soviet Union and the demographic expansion of autochthonous, relic population at the Biebrza valley. Starting for 1952 the species was strictly protected and in 1967, when population was about 600 individuals, the sustainable harvest (hunting) was established. Demographic expansion of moose populations continued through 60. and 70-ties of the XXth century and resulted in its maximum (ca 6200 individuals) in 1981. The moose was present at Polish lowlands and reached the German boundary. Unfortunately, overhunting that continued for over 20 years became a considerable threat to a species and their numbers were reduced by over 70%. Many populations in western and central Poland became extinct till 2001. The reduction was explained by demands of forest protection, as moose in Poland caused significant damages in young-growth forests. As the species became endangered, no hunting is allowed since 2001. This decision of the Ministry of Environment resulted in the recovery of moose populations and the species is now abundant, especially in eastern part of Poland. The future of the moose in Poland will depend on "The strategy for moose protection and management", being prepared by a team of scientists, National Forest Holding and Polish Hunting Association. This evidence based-management plans should help to maintain viable populations and lower the damages in young-growth forests as well as the risk of car accidents with moose.
4

Zastosowanie technik molekularnych w ekologii

63%
Ratkiewicz M., Borkowska A.
Wiadomości Ekologiczne
|
2002
|
tom 48
|
nr 2
99-121
5

Genetic structure is influenced by environmental barriers: empirical evidence from the common vole Microtus arvalis

63%
Ratkiewicz M., Borkowska A.
Acta Theriologica
|
2006
|
tom 51
|
nr 4
337-344
One of the major challenges in population biology is the identification of barriers to gene flow and/or secondary contacts between differentiated entities. The level of genetic differentiation among eight populations of the common voleMicrotus arvalis (Pallas, 1779) around the Biebrza Wetlands, NE Poland was examined by analyzing seven microsatellite loci for 140 voles and testing for the presence of barriers to gene flow. Overall population differentiation was moderate and significant (F ST = 0.081,p < 0.001) and there was no correlation between geographical and genetic distances among populations. We found a relatively high level of genetic variability within the populations studied. This could be explained by male bias in dispersal, a phenomenon recently found inM. arvalis. Patterns of genetic structure visualized in synthetic genetic maps showed clear gradients along a southeast-northwest axis across the study area, as well as the presence of a potential barrier to dispersal. The position of a barrier to gene flow identified using Monmonier’s maximum difference algorithm likely corresponds to humid habitats of the Biebrza Wetlands. These results suggest that the presence of environmental barriers to gene flow and drift may be responsible for the observed spatial genetic structure ofM. arvalis in the Biebrza Valley. Institute of Biology, University of Białystok, OEwierkowa 20 B, 15-950 Białystok, Poland,
6

Markery molekularne - narzedzia w badaniu dyspersji osobnikow roznej plci

63%
Borkowska A., Ratkiewicz M.
Wiadomości Ekologiczne
|
2004
|
tom 50
|
nr 1
3-17
7

Does biotope diversity promote an increase of genetic variation in the bank vole population ?

63%
Gebczynski M., Ratkiewicz M.
Acta Theriologica
|
1998
|
tom 43
|
nr 2
An electrophoretic study of the variation at 40 protein loci in the bank vole Clethrionomys glareolus {Schreber, 1780) was performed in spring 1994-1996 and in autumn 1994 and 1995. A total of 153 individuals from deciduous forest and 122 from coniferous forest subpopulations were collected. During the whole time of the study in spring the coefficient of trappability was 4.1% in deciduous forest and 3.0% in coniferous forest; in autumn 9.3% and 7.6%, respectively. In spring there were no significant differences in allele frequencies between the subpopulations studied. The samples from deciduous and coniferous forests were genetically similar. However, in autumn these differences were statistically significant. Although the level of hetero­zygosity in both, neighbouring subpopulations is similar, its changes in consecutive seasons have different values. From the calculations performed, based on the level of genetic differentiation between subpopulations (Fst), it can be concluded that the level of gene flow between the voles from two biotopes in spring is greater than in autumn. We hypothesise that the essence of this phenomenon lies in a non-random fraction of migrants between the biotopes studied. The data presented in the study indicate that the genetic structure in two neighbouring subpopulations of the bank vole undergoes different processes.
8

Relationships between allozyme heterozygosity and gut morphology in Apodemus agrarius

63%
Borkowska A., Ratkiewicz M.
Acta Theriologica
|
1996
|
tom 41
|
nr 4
We studied enzyme polymorphisms in a striped field mouse Apodemus agrarius (Pallas, 1771) population from NE Poland and the relationships between hetero­zygosity and length and mass of the digestive tract organs, and the mucosal surface area of the small intestine. _Most of 38 loci studied were found monomorphic (pro­portion of polymorphic loci P = 0.053, observed average heterozygosity H0 = 0.021). Heterozygotes were found for Acy, Pgm-1, Mdh-2, Est-D, Pgi, Sdh and Trf. Hetero­zygous males had longer large intestines and ceca and smaller liver wet mass than their homozygous conterparts. However, in females there were no significant inter­actions between heterozygosity and gut parameters. We suggest that the low level of polymorphism, the particular set of the loci examined and sex have an effect on detection of differences between heterozygous and homozygous individuals.
9

Admixture promotes genetic variation in bottlenecked moose populations in eastern Poland

51%
Swislocka M., Czajkowska M., Duda N., Ratkiewicz M.
Acta Theriologica
|
2015
|
tom 60
|
nr 2
Human activity has led to severe bottlenecks in many wildlife species in the recent past. This usually increases the strength of genetic drift, leading to loss of genetic variation. Gene flow may however counteract the genetic consequences of small population size. Using 11 of 38 tested microsatellite loci and five moose populations in eastern Poland, we investigated the effects of two phenomena: bottlenecks that occurred in the nineteenth century and the first half of twentieth century, and admixture after moose populations expanded demographically and spatially in eastern Poland after the Second World War. The statistical tests indicated a recent bottleneck in all the studied samples with respect to H E and low Garza–Williamson index values. The Biebrza population, which consists of autochthonous moose representing a branch of the Central Europe mitochondrial DNA (mtDNA) clade and immigrants belonging to the Ural clade, is one of the most variable populations of this species. AMOVA, PCA, and STRUCTURE analyses all revealed significant population structuring, with most probable existence of K = 2 genetically distinct clusters that exhibited a relatively high level of admixture. Analysis of recent dispersal rates demonstrated that population from the Biebrza Valley may supply individuals to the other four studied moose populations. We also found female-biased sex ratio in nonharvested moose populations inhabiting eastern Poland.
10

Maintenance of genetic variation and moderate differentiation among populations under sex-biased dispersal in the common vole Microtus arvalis in patchy habitats

51%
Borkowska A., Ratkiewicz M., Jaarola M.
Acta Theriologica
|
2010
|
tom 55
|
nr 4
We present a microgeographic analysis of 34 allozyme loci and the control region of mitochondrial DNA (mtDNA) in the common voleMicrotus arvalis (Pallas, 1779), performed to assess the effects of environmental heterogeneity on the distribution of genetic variation among populations in the Biebrza river valley, NE Poland. The common vole occurs there in two types of habitat: open grassland and pastures around the valley (GP populations); and abandoned fields on small hills isolated by wetlands (SH populations). No significant genetic differences were found between SH and GP populations with respect to allelic richness, nor average observed and expected heterozygosities. The average genetic differentiation at allozyme loci among the SH populations was significantly lower (F ST =0.066) than among the GP populations located around the Biebrza valley (F ST =0.112), and an isolation by distance pattern was detected (r=0.26,pr<0.05). Mitochondrial DNA differentiation among the GP populations was great (F ST =0.357,p<0.01), indicating that female dispersal was 4.4–6.5 times lower than for males. Our results and reviewed published data onM. arvalis dispersal suggest that common vole dispersal in patchy natural and semi-natural habitats is male-biased and could generate moderate population divergence, with relatively high levels of genetic variation retained within populations.
11

Low genetic diversity and significant structuring of the common hamster populations Cricetus cricetus in Poland revealed by the mtDNA control region sequence variation

51%
Banaszek A., Jadwiszczak K. A., Ratkiewicz M., Ziomek J.
Acta Theriologica
|
2009
|
tom 54
|
nr 4
289-295
The genetic diversity of 12 populations in the present range of the common hamster Cricetus cricetus (Linnaeus, 1758) in Poland was established. The 366 bp of the mtDNA control region was sequenced for 195 individuals. As few as seven haplotypes were found and their distribution was geographically structured. The large geographic areas were fixed or almost fixed for a single haplotype and three groups of populations, that do not share any haplotypes, have been defined. Proportions of genetic diversity attributable to variation between groups of populations, between populations within groups and within populations were 93.64, 1.92 and 4.45% (SAMOVA: p < 0.001 for all estimates), respectively. Such pattern of variation is most probably the result of historical, postglacial bottlenecks and present genetic drift after the population decline in the last few decades.
12

Evolution of the common shrew Sorex araneus: chromosomal and molecular aspects

51%
Wojcik J. M., Ratkiewicz M., Searle J. B.
Acta Theriologica. Supplement
|
2002
|
tom 47
|
nr 1
We review data on the chromosomal variation in the common shrew Sorex araneus Linnaeus, 1758 in the context of recent molecular findings. The article considers all aspects of chromosomal variation in this species: within-population polymorphism, karyotypic races, hybrid zones between karyotypic races, chromosomal evolution, and speciation. The recent molecular data provide vital information on different evolutionary processes such as inbreeding, genetic drift, population expansion, and selective forces. In particular, the molecular data challenge traditional models for the fixation of chro­mosomal variants, provide new insights into the manner of spread of such variants once they are formed and allow in-depth analysis of gene exchange between karyotypic races.
13

Zroznicowanie mitochondrialnego DNA oraz przeplyw genow miedzy populacjami losia [Alces alces L.] w Dolinie Biebrzy i Puszczy Augustowskiej

39%
Swislocka M., Ratkiewicz M., Raczynski J., Duda N., Borkowska A., Komenda E.
Parki Narodowe i Rezerwaty Przyrody
|
2009
|
tom 28
|
nr 1
95-106
14

Zimowa dieta łosia

39%
Czernik M., Swislocka M., Czajkowska M., Duda N., Borkowska A., Ratkiewicz M.
Głos Lasu
|
2014
|
nr 03
15

Complex patterns of population genetic structure of moose, Alces alces , after recent spatial expansion in Poland revealed by sex-linked markers

39%
Swislocka M., Czajkowska M., Duda N., Danylow J., Owadowska-Cornil E., Ratkiewicz M.
Acta Theriologica
|
2013
|
tom 58
|
nr 4
In recent years, human activity directly and indirectly influenced the demography of moose in Poland. The species was close to extinction, and only a few isolated populations survived after the Second World War; then, unprecedented demographic and spatial expansions had occurred, possibly generating a very complex pattern of population genetic structure at the present-day margins of the species range in Poland. Over 370 moose from seven populations were collected from Poland, and partial sequences of the mitochondrial control region (mtDNA-cr; 607 bp) were obtained. In addition, the entire mtDNA cytochrome b gene (1,140 bp) and Y-chromosome markers (1,982 bp in total) were studied in a chosen set of individuals. Twelve mtDNA haplotypes that all belonged to the European moose phylogroup were recorded. They could be divided into two distinct clades: Central Europe and the Ural Mountains. The first clade consists of three distinct groups/branches: Biebrza, Polesie, and Fennoscandia. The Biebrza group has experienced spatial and demographic expansion in the recent past. Average genetic differentiation among moose populations in Poland at mtDNA-cr was great and significant (Φ ST = 0.407, p < 0.001). Using mtDNA-cr data, four separate groups of population were recognized using spatial analysis of molecular variance and principal coordinate analysis, including a relict population in Biebrza National Park, a reintroduced Kampinos National Park population, as well as populations that were descendants of moose that colonized Poland from the east (Lithuania, Belarus, and Ukraine) and the north (former East Prussia). Among all the sequenced Y-chromosome markers, polymorphisms were found in the DBY14 marker in three populations only; four haplotypes were recorded in total. No significant differentiation was detected for this Y-linked marker among moose populations in Poland. Our mtDNA study revealed that a variety of different factors—bottleneck, the presence of relict, autochthonous populations, translocations, limited female dispersal, and the colonization from the east and north—are responsible for the observed complex pattern of population genetic structure after demographic and spatial expansion of moose in Poland.
16

Ocena rozmieszczenia i liczebności niedźwiedzia brunatnego Ursus arctos (L.) we wschodniej części polskich Karpat

39%
Smietana W., Matosiuk M., Czajkowska M., Ratkiewicz M., Rutkowski R., Bus-Kieman M., Jakimiuk S.
Roczniki Bieszczadzkie
|
2014
|
tom 22
17

Fast and efficient DNA-based method for winter diet analysis from stools of three cervids: moose, red deer, and roe deer

39%
Czernik M., Taberlet P., Swislocka M., Czajkowska M., Duda N., Ratkiewicz M.
Acta Theriologica
|
2013
|
tom 58
|
nr 4
Effects of cervid browsing on timber production, especially during winter, lead to economic losses in forest management. The aim of this study was to present an efficient DNA-based method which allows qualitative assessment of the winter diet from stools of moose (Alces alces), roe deer (Capreolus capreolus), and red deer (Cervus elaphus). The preliminary results of the diet composition of the three cervids from Poland were also presented with a special emphasis on moose. The electropherograms of the chloroplast intron trnL (UAA) P6 loop amplification products using g (fluorescence-labeled) and h primers revealed differences in the length of PCR products among various plant species eaten by these herbivores. In addition, the usage of species-specific primers allowed unambiguous identification of different gymnosperms and angiosperms. The preliminary moose diet analysis, based on winter fecal samples from the entire range of moose occurrence in Poland, revealed the presence of 15 to 24 tree, shrub, and herbaceous species. This fast, cost-efficient, and simple method proved also to be reliable for the diet analysis of red deer and roe deer. It may be a valuable tool in forest and conservation management, as well as a way of enhancing ecological studies focusing on the impact of herbivores on the ecosystems and their possible food niche overlap.
18

Genetic differentiation and gene flow between the Drnholec and Legucki Mlyn chromosome races of the common shrew Sorex araneus in Northern Poland

39%
Ratkiewicz M., Supruniuk J., Fedyk S., Banaszek A., Chetnicki W., Szalaj K. A.
Acta Theriologica. Supplement
|
2000
|
tom 45
|
nr 1
19

Łoś wychodzi z ukrycia

38%
Ratkiewicz M.
Mój Piękny Ogród
|
2012
|
nr 10
20

Sarna pełna tajemnic

32%
Ratkiewicz M., Matosiuk M.
Mój Piękny Ogród
|
2012
|
nr 12
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