卷 45, 编号 1 (2018)

We studied the male generative sphere in the populations of Pinus sibirica Du Tour growing in forest bog ecosystems of the southern taiga subzone of western Siberia. Significant differences in the morphological and palynological characteristics were found in specific microclimatic and edaphocenotic growing conditions on the upland and on the ecotone between the upland and the bog.

Two types of surface tactile epidermal formations are identified in the bill tip organ of 11 species of lamellirostral birds. Their density arrangement and ratio in the mandible and maxilla are greater in dabbling ducks (filter-feeder species) than in herbivorous and in actively pursuing species. The length and proportions of the connective tissue tubules enclosing the encapsulated mechanoreceptors in filter-feeder species differ significantly from the others. The vibroreceptor endings are significantly more numerous in filter-feeder species and the touch endings in nonfiltering ones. The latter are smaller in the filter-feeder species. Within the walls of the connective tissue tubules, tactile epitheliocytes are registered for the first time. The structure of keratinocytes separating epidermal papillae of the bill tip organ apparently ensures their mobility. The bill tip organ is probably involved in the communication process of waterfowl.

This work has demonstrated that the life stages of the Hermetia illucens fly are characterized by varying melanin contents with the maximum melanin amount being detected in the pupa. It has been observed that active synthesis of the pigment takes place in the prepupa and coincides with the time when the population migrated for pupation. It has been noted that a high manganese content in the prepupa and pupa indicates the important role that this biogenic element plays in organogenesis and melanogenesis in H. illucens. It has been revealed that in the imago and pupa, the melanin demonstrates broad-range antimicrobial activity and contribute to the insect protection against bacterial and fungal infections.

The results of urease activity studies in the digestive tract of muroid rodents Microtus socialis and Meriones meridianus are considered. It was noted that the absolute values of urease activity turned out to be comparable with those of lagomorphs, but were less than the results obtained for ungulates. The pronounced postgastric character of urealytic fermentation was shown. The possibility of significant urea recycling in muroid rodents aimed at compensating for dietary nitrogen deficiency and water conservation is considered.

Stress reactions with activation of the sympathetic-adrenal system due to acute hypoxia reflects the degree of sensitivity of the body to this extreme factor. Succinate dehydrogenase (SDH) activation in cells as an adaptive response to acute hypoxia is closely associated with the degree of disturbance of tissue respiration through a lack of oxygen in the tissues, including the manifestation of “biochemical shock,” which is an unavoidable component of implementation of the protective effect of radioprotectors. In experiments on mice, rats, and dogs, the correlation between the manifestation of the radioprotective effect of acute hypoxia and SDH activation in blood lymphocytes, caused primarily by adrenergic stimulation during stress reactions, is confirmed. The degree of SDH activation in blood lymphocytes by hypoxia of different origins including that induced by radioprotectors may indicate its radioprotective potential irrespective of the differences in the oxygen consumption intensity and the resistance to acute hypoxia in animals and humans.

An analysis of research data and published data on comparable standard metabolism in invertebrates is carried out. It is shown that this parameter varies insignificantly within each family and most orders. The mean values of the comparable standard metabolism for orders are grouped around certain values. It is assumed that these values correspond to stationary states, which organisms seek to reach during the evolutionary process. A total of nine levels of stationary states have been identified. The ratio of the values of comparable standard metabolism for neighboring levels is approximately 2.25. The orders occupy ever higher stationary levels in the process of macroevolution of phyla and classes. A possible mechanism for the transition from one stationary level to another is discussed.

Sequencing of two regions of mitochondrial DNA, CytB (1124 bp) and COI (629 bp), is conducted for the first time for pond smelt Hypomesus olidus (Osmeridae) from the Commander Islands. The haplotypes identified, H1 and H2, differ by one mutation in the region of the COI gene. Haplotype H1 that belongs to the pond smelt from the Commander Islands was previously massively found in pond smelt of Azabache Lake. Haplotype H2 was not found previously and is probably unique to pond smelt from the Commander Islands.

The short-day plant stevia (Stevia rebaudiana) was earlier reported to produce electron-dense thylakoids in the chloroplasts under long-day conditions. In the present work, such thylakoids were analyzed by transmission electron microscopy and gas chromatography–mass spectrometry. It was found that they contain glyceryl tricaprate, which belongs to triacylglycerols. A hypothesis is advanced that glyceryl tricaprate acts as a photoprotector for short-day plants against redundant solar radiation.

The formation of early fouling communities developing under different spatial orientations of substrates and various lighting conditions was studied during a field experiment. The algal predominance on the sunlit upward-oriented sides and the animal predominance on the shaded downward-oriented sides are the consequence of two processes: (1) competitive displacement of animals from the sunlit sides by algae; (2) preferential colonization of the shaded downward-oriented sides of the substrates by animals.

This paper studies the impact of a free-ranging bison population on the vegetation and soil fauna in spatially adjacent biotopes (meadow-transition zone-surrounding forest) in the Kaluzhskie Zaseki State Nature Reserve. It is noted that bison maintains meadows in the absence of haymaking. Analysis of phytosociological relevés shows that the forest vegetation has been significantly transformed by bison over 10–15 years, as evident from (1) differences in the ecological-coenotic structure of the vegetation in the different biotopes, (2) a larger ecological-coenotic diversity of communities in the transition zones in comparison with surrounding forests, and (3) an increase in the participation of nitrophilous species in the vegetation. A fairly high earthworm species diversity (a total of seven species in the biotopes) is found; Aporrectodea caliginosa dominates in the earthworm density and biomass. The total earthworm density and biomass became lower in the transition zone than in neighboring forests and meadows, and the differences in earthworm density between the transition zone and the meadows were statistically significant.