Can Shrews Avoid Competition When Hutchinson's Ecological Rule Is Disobeyed?

It is established that Hutchinson's ratio of the weights and sizes of the body and foraging organs in similar species is not fully obeyed in shrew species of the genus Sorex. Similarity in the centroid size of the mandible was observed in the large species S. isodon and S. araneus. Differences in the shape of the mandible, which is intensely used in foraging, were detected between the species by geometric morphometrics. Interspecific differences were found in mandibular indices, which reflect trophic specialization and functional features of the mandibles. Shrews can therefore avoid competition even when Hutchinson's rule is violated. The avoidance is due to a transformation and specialization of the mandible and changes in prey capture methods and diet, rather than to changes in size. Hutchinson's ecological rule is thus not mandatory, but is only one of the conditions for reducing competition between closely related species.

Lifespans of Fur Color Morphs in Polymorphic Populations of the Mole Vole and the Hypothesis of Adaptive Polymorphism.

Different lifespans were for the first time demonstrated for three (brown, bicolor, and black) fur color morphs in ten mole vole populations of the Volga, Ural, and Trans-Ural regions. With the longest lifespan of 5 years in the species, morphs that numerically dominate in a population can live 1-4 years longer than accompanying morphs. Spearman's correlation coefficient between the longest lifespan of the morphs and their proportion in the population was Rsp = 0.81 (p < 0.0001). A number of morphological and functional features were identified in the color morphs. The findings are of general biological significance, confirming the hypothesis of adaptive polymorphism. Evolutionary and ecological mechanisms whereby selective advantages develop in morphs (as probable ecomorphs) are possible to evaluate using the morphs as a natural model of the initial step of sympatric form development in different parts of the range.

Genetic Diversity of Species of Microtus Generic Group (Arvicolinae, Rodentia): New Data from the Greater Caucasus.

Using the cytochrome b gene (1143 bp), species identification and the phylogenetic analysis of voles of the generic group Microtus from the eastern part of the Greater Caucasus, including the Ismayilli, Khizi, and Balakan Districts of Azerbaijan, have been carried out. Three species, the Major's pine vole (M. majori), the social vole (M. socialis), and the common vole (M. arvalis form obscurus), have been identified, and five new haplotypes have been described for them. Genetic analysis with the inclusion of the new data showed that for each of the species, the physiographic conditions of the Greater Caucasus played a certain role (isolation, migration route or refugium) during the formation of the modern genetic structure. The obtained results indicate that any new data from the Caucasus could be of critical importance for the reconstruction of the evolutionary history of the modern biodiversity both within the region itself and in adjacent territories.

Analysis of Geographical Variability of Morphogenetic Trajectories Using the Mole Vole (Ellobius talpinus Pall.) as an Example.

ABSTTRACT: -Using the methods of geometric morphometrics, we have revealed the phenomenon of geographical variability of morphogenetic trajectories when doing side-by-side comparisons of mandibular shapes in individuals of different ages from three southern Trans-Ural populations of the mole vole (Ellobius talpinus Pall.) in the common morphospace.

New Data on the Holocene Mammal Fauna of the Ustyurt Plateau.

Analysis of mammalian species composition has been performed for eight archaeological sites on the Ustyurt plateau. They date to the range from the middle Subboreal to the middle Subatlantic. The modern species composition of large mammals formed by the end of the Middle Holocene (Subboreal 2) and did not change until the early 20th century. The ungulate species composition and ratio on the plateau showed geographical variation and changed over time. Boars were always rare or absent in the north of Ustyurt. The structure of the ungulate fauna in the north of Ustyurt changed over time. Onager numbers in this area increased and saiga numbers decreased in the middle of the Late Holocene. Significant geographical differences in the structure of ungulate fauna were recorded in the middle of the Late Holocene. The numbers of onagers, goitered gazelles, and argali were higher, whereas the numbers of saigas were lower in the south of Ustyurt than in the north.

Morphogenetic Effects of Resettlement of Mole Voles (Ellobius talpinus Pall., 1770) from the Southern Population to the Northern Boundary of the Species Range.

Geometric morphometry has been used to reveal transformations of mandible morphogenesis in the offspring of mole voles resettled to the northern part of the species range from a southern population. The transformations were new compared to both the original (southern) and the aboriginal (northern) populations. A significant increase in the intragroup morphological disparity estimated by the mean nearest neighbor distance (MNND) in the resettled animals compared to both aboriginal populations is an indirect indication of an increased developmental instability in the resettled animals exposed to new climatic conditions.

Distinct features of intraspecific and intrapopulation variability of the skull size in the red fox.

The range of chronographic variability of the average size of the skull in the red fox (data collected by the authors) from a compact area in the Middle Urals has been assessed for a 30-year period, and the results obtained have been compared with the published data on the geographical variability within the vast species range. The range of changes of the average dimensions of the skull over time spanned almost the entire range of geographical variability. Therefore, the problem of search for factors that determine the morphological diversity arises.

[The role of the Urals in the genetic diversity of the European moose subspecies (Alces alces alces)].

The genetic diversity of the Uralian moose population and the role of the Ural region in the phylogeographic structure of the European moose were evaluated based on sequence polymorphisms of the mtDNA control region. The nucleotide diversity of the Ural moose was low, whereas haplotype diversity was rather high. It was found that the haplotype pool of the Ural moose reflects both the unique features of their mitochondrial lineages and their connection with Alces alces alces populations of Europe and West Siberia. The structure of median networks and the territorial haplotype distribution support the hypothesis that the mitochondrial lineages typical for this part of the European moose area originate from a late Pleistocene refugium that was located in the Urals.

[Changes in the duration of replication of the polytene chromosome region during position effect in Drosophila melanogaster]. / Izmenenie vremeni replikatsii raiona politennoi khromosomy pri éffekte polozheniia u Drosophila melanogaster.

Replication pattern of the X chromosome 2B region translocated to the pericentric heterochromatin in the 2L chromosome within the T(1; 2) dorvar7 rearrangement which causes position effect was studied. It was found that this pattern is affected by the 2B region morphology. When normal, i.e. with decondensed bands in this region, it completes replication early. But after compaction, i.e. fusion of bands in the 2B region into dense block, due to position effect, its late replication was observed, together with the most late replicating intercalary heterochromatin regions in the X chromosome and the 75C-80A-C segment of the 3L chromosome. Possible mechanisms of replication delay and their role in promoting the position effect are discussed.

[Changes in the properties of intercalary heterochromatin in Drosophila melanogaster induced by position effect modifiers]. / Izmenenie proiavleniia svoistv interkaliarnogo geterokhromatina u Drosophila melanogaster pod vliianiem modifikatorov éffekta polozheniia.

Compaction of chromosome regions translocated to the pericentric heterochromatin and the break frequency in intercalary heterochromatin (IH) regions as affected by position effect modifiers (low temperature, removing the Y chromosome, genetic enhancers and suppressors) were studied. It has been shown that the factors enhancing compaction also increase the break frequency in IH regions. Data obtained are discussed from the point of view of proteins affecting the compaction of intercalary and pericentric heterochromatin regions translocated to heterochromatin under position effect.

[Higher military medical education: its developmental outlook]. / Vysshee voenno-meditsinskoe obrazovanie: perspektivy razvitiia.

The authors of the article--the employees of the main military-medical management of the DD of the RF--discuss a way of realization of the programs of the higher military education (1998) in the military-medical high schools of the Armed Forces. Since 1998 the preparation of the general practice doctors is planned with the introduction of the federal nomenclature of this specialty in the troops. The tendency to practical directions of the doctor's preparation to a particular post--"under a working place" will be amplified. The main form of the post-graduated vocational training are training on the faculty of the military-medical management of the military-medical academy and in the clinical post-diploma course of the military-medical colleges. Since 1998 at expansion of the total volumes of the training at the clinical post-diploma course in 3 times an enrollment to the faculty of the military-medical management of the academy will be reduced. Since 1998 at the command department of the military-medical academy only "the organizers", "the preventive maintenance specialists" and "medproviders" will learn. Since 1998/99 educational years, reception of the women in military-medical colleges will be terminated.

[The organizational aspects of medical support for the troops in armed conflicts]. / Nekotorye organizatsionnye aspekty meditsinskogo obespecheniia voisk v vooruzhennykh konfliktakh.

The theory of medical maintenance adopted for young military teachers to help them to organize the course of "Medical Maintenance" discipline within educational programmes of military schools. The article focuses on the main principles of troops medical maintenance and supply.