Publications by authors named "N A Shchipanov"

Among 36 known chromosomal hybrid zones of the common shrew Sorex araneus, the Moscow-Seliger hybrid zone is of special interest because inter-racial complex heterozygotes (F hybrids) produce the longest meiotic configuration, consisting of 11 chromosomes with monobrachial homology (undecavalent or chain-of-eleven: CXI). Different studies suggest that such a multivalent may negatively affect meiotic progression and in general should significantly reduce fertility of hybrids. In this work, by immunocytochemical and electron microscopy methods, we investigated for the first time chromosome synapsis, recombination and meiotic silencing in pachytene spermatocytes of natural inter-racial heterozygous shrew males carrying CXI configurations.

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The spatial genetic structure is a topical issue in the studies of various aspects of ecology and evolution. Using the multilocus autocorrelation method with hypervariable microsatellite genetic markers, we investigated a fine-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300-1000 m (the Moscow chromosomal race). Spatial genetic autocorrelation analysis based on 5 microsatellite loci (expected heterozygosity >0.

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The specific aim of our study was to test individual common shrews from a population monitored long-term. In a preference test, we revealed sex-related differences in behavioral traits of young common shrews and consistent individual differences in sociability, boldness and in an exploration pattern that have not been reported previously. More active animals were bolder and more superficial in the exploration of non-social objects as compared to shier shrews.

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The skulls of shrews of genus Sorex from eight samplings from the European part of Russia and two from the vicinity of Novosibirsk were compared. The characteristics were identified using 22 marks on the axial skull. It was found that the centroid size differs significantly in the common and Laxmann's shrews S.

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Sorex araneus, the Common shrew, is a species with more than 70 karyotypic races, many of which form parapatric hybrid zones, making it a model for studying chromosomal speciation. Hybrids between races have reduced fitness, but microsatellite markers have demonstrated considerable gene flow between them, calling into question whether the chromosomal barriers actually do contribute to genetic divergence. We studied phenotypic clines across two hybrid zones with especially complex heterozygotes.

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