[Decentralized self-regulation of the integrity of colonial organisms]. / Netsentralizovannaia samoreguliatsiia tselostnosti kolonial'nykh organizmov.

The self-regulation of the integrity of colonial organism is accomplished without any central system organs. Abundance of similar structures, parallelism and synchrony of the processes form the basis for self-regulation, thus creating the independent mechanism of the internal coordination of the processes. Decentralized regulation of the integrity is much more economical then the centralized regulation, because it does not demand large volume of information, consequent increase in complexity of its processing and unavoidable problems with coordination. The principles of decentralized self-regulation, addressed in this paper, can be use not only in biology, but also in sociology, psychology, modeling, neuroformatics, etc.

[Effect of variable phases of tide cycle on reproduction of Laomedea flexuosa (Hydroidea, Thecaphora]. / Zavisimost' razmnozhenia gidroida Laomedea flexuosa (Hydroidea: Thecaphora) ot stadii prilivnogo tsikla.

Colonial hydroid Laomedea flexuosa inhabits the narrow belt of low littoral zone in the White Sea. What is a reason of so limited habitat? The authors studied the time of planulae release and its behavior during free swimming stages and settlement of larvae in nature and under laboratory conditions. Three methods were used to registrate the tidal dependent dynamic of planulae release: 1) plankton collecting bags around Fucus inflatus kelp with mature hydroids colonies; 2) active stirring kelps with hydroids in container with water, which is an old way to stimulate planulae release; 3) direct account of the mature planulae into gonangia. The dynamic of intensity of L. flexuosa planulae release was investigated according 3-4 phases of tidal cycle. All data were statistically tested. For L. flexuosa a moment of general larvae release was found in phase with the period of low water. This correlation could explain strict limitation in occurrence of L. flexuosa only in the lower part of intertidal zone. Laboratory experiments show that planulae release is stimulated by littoral drainage, and renewal of water movement during the beginning of tide. The decrease in time of planulae settlement is an affective way for marine sedentary species to stay in a narrow zone of optimal habitat.