The influence of symphysiologic connections of both of the 

 complexes studied was thus manifested in a very narrow range of change 

 of the effective factor--the specific hydroid growth rate (complex I) 

 and the relative Tenellia population density (complex II)--within limits 

 confined to the "effective range" of the complex of connections. 

 Outside the limits of this range, with a lower intensity of the 

 effective factor the influence of the connections is not felt, and the 

 development of the dependent species is determined by its ecologic 

 peculiarities under the specific conditions at hand; with higher 

 intensity of the effective factor, the dependent species is destroyed. 

 In turn, changes in the intensity of the effective factors are 

 determined by the presence of modifier species: the Vorticella and 

 Tenellia . The intraspecific connection coefficients of both these 

 species were found to be much higher than the interspecific connection 

 coefficients. This agrees with the ecologic theory, according to which 

 intraspecific competition, with high populations, is more acute than 

 interspecific competition (Shorygin, 1939, 1946). 



Long-term changes in the intensity of connections can be presumed 

 in those cases when a slow increase in biomass or abundance of the 

 conditioning species occurs. However, a high abundance or biomass of a 

 conditioning species cannot be used as an indication of great intensity 

 of a connection. According to the materials of the FFE, the greatest 

 value of relative intensity was that of connection 5 (version 8), where 

 the population of the conditioning species ( Tenellia) was quite low 

 throughout the entire experiment, while the development of the dependent 

 species (hydroid) was suppressed at the very beginning. The 

 symphysiologic connections with high intensity of action modeled in the 

 FFE rapidly stopped the growth of the population of the dependent 

 species by its elimination; connections with low intensity acted slowly, 

 and the dependent species continued to develop. 



In the natural overgrowth community, the symphysiologic connections 

 modeled in the FFE function at different times. The time divergence of 

 the action of the various connections is caused, on the one hand, by the 

 seasonal differences in the time of settling of larvae, determining the 

 seasonal succession of complexes of the connection, and, on the other 

 hand, by time differences in occurrence of the maximal abundance of the 

 various species of animals, defining the sequence of functioning of the 

 connections of each complex. For example, in spring, after settling of 

 the hydroid and Balanus larvae, when the young stolons of the hydroid 

 are free of epibionts, the action of connection 1 is evident. After 

 some time has passed, the Vorticella develops on the 4 to 6-day old 

 stolons of the hydroid, and connection 3 begins to function, which, with 

 intensive development of the hydroid, usually causes mass mortality of 

 the young Balanus . In mid- summer, with mass development of the 

 Tenellia , connections begin to function which suppress the hydroid; at 

 first connection 8, decreasing the growth rate of the colonies, then 

 connection 5, suppressing its vital activity. As the Tenellia 

 population increases, intraspecific connection 9 begins to function, the 

 intensity of which apparently gradually increases. After the vital 

 activity of the hydroid is suppressed, the intensity of connection 9 

 reaches its maximum, most of the individual Tenellia are expelled from 

 the community, and the remaining small portion, temporarily go over 



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