The concepts of centers of biota origin and centers of biota accumulation are usually considered as alternative ones. The paper analyzes them within a united conception of centers of biota redistribution. Center of redistri- bution represents a biogeographical unit, which has three developmental stages: accumulation, diversification, and dispersal. At the accumulation stage, the taxonomic capacity of a biogeographical district increases drasti- cally, and the species richness becomes higher due to the penetration of species from other regions. At the stage of diversification, the species richness continues to increase due to speciation, a united succession system de- velops. At the stage of dispersal, the biotic boundaries of the region act as efficient barriers for species coloni- zation. The species of the center of redistribution have an advantage over the species of adjacent regions when colonizing new habitats. In the Neogene, the main centers of redistribution of the marine fauna characteristic of shallow areas were located in the Indo-Malayan "triangle," the western Atlantic and the northern Pacific Ocean. For deep oceanic areas, the role of redistribution belonged to the Antarctic and the western Pacific. The possibility to use an ecosystem approach to study the centers of redistribution is discussed.
Shchipanov N.A., Aleksandrov D. Yu., Aleksandrova A.V.
The distribution of micromycete spores was studied in soil litter and on the fur of small mammals
Tsellarius A. Yu., Tsellarius E. Yu.
The territory of male was formed around centers of the activity of settled females. A young male obtained an access to these centers only in the case when the territorial male died and new centers had been formed within his home range. A direct aggression towards other males appeared when the male obtained an access to regular contacts with females. This access might be unlimited when all or the majority of the centers of female activity were within the male territory (α-males). The access might be partly limited when the territory contained only one or few such centers (β-males). In α-males, the obligatory aggression of high intensity was provoked by the behavior of an intruder, which as improper for its status, or by the attempts to rape any female. The intruder's courting to female provoked aggression only in 80% of instances. The most intense aggression of β-male was caused by the intruders' attempts to court the female that was preferable for him or by his invasion into the her activity center. The territories of males with different status proved to differ in both the motivation of their be- havior and their position in a system of social relationships and use of resources.
A review of principles for application of karyotype features in systematics of parasitic Hymenoptera is given. Specific character of using chromosomal characteristics at different taxonomic levels is determined. The data on morphology of karyotype play the most important part in the systematics of parasitic wasps on the species level. Closely related forms of parasitic Hymenoptera that differ in structural features of their chromosomal sets may be divided by their taxonomic level and degree of morphological isolation into the following categories: well-distinguished species; species with weak differences in external morphology (sibling species sensu stric- to); morphologically identical populations; intrapopulation forms; individuals with spontaneous chromosomal mutations. Chromosomal research is proposed to use in the systematics of parasitic Hymenoptera as an express method for analysis of natural populations and laboratory stocks of these insects.
Kadyrbekov R. Kh.
Dokuchaev N.E., Dorogoi I.V.
The distribution of
Panov E.N., Nepomnyashchikh V.A., Rubtsov A.S.
A prolonged phonogram obtained within two early morning hours from the single tree pipit
Sokolov V.I., Milyutin D.M.
The behavior of red king crab groups of different size was observed during diving investigations at the coastal zone of the Kola Peninsula in the summer periods of 2002-2003. In the Barents Sea, young immature indivi- duals are shown to lead a settled way of life up to the age of 3
Reznik S. Ya., Vagina N.P.
The effects of temperature on the induction and stability of infestation of eggs in the less preferable factitious host by
The new psammophilous ciliate,
The type specimens of the species
Gagarin V.G., Nguen Vu Thanh
Three new species of free-living nematodes of the genus