Zh Obshch Biol
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The structure of planktic trophic chains was studied in eight lakes of European Russia and five lakes in Central Asia. The lakes differed in the level of productivity, morphometric parameters, and the type of agitation and mineralization. ⋯ The presence of a great number of cladocerans decreased the role of the microbial loop in the structural organization of the planktic community. Heterotrophic flagellates consuming 3-81% of daily bacterial production were the principal cause of bacteria elimination only in some of the studied water bodies.
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Comparative Study
[Computer simulation of different types of evolutionary process].
The computer model of two alternative variants of biological evolution is proposed. The first variant supposes random while the second--directed change of individual features, thus corresponding to the Darwinian and non-Darwinian evolution. The evolution of fish communities in fresh waters serves as a particular example. ⋯ On the other hand, non-Darwinian type of evolution provides fast achievement of high individual fitness, especially under conditions of constant environment. Non-Darwinian type evolution failed in big evolutionary alteration (for example, transition to predation); while the Darwinian evolution under the same conditions can produce such alterations though it took more time and many extinct species. Phylogenetic tree of Darwinian evolution is always more complex than of non-Darwinian one under the same conditions.
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Review Comparative Study
[The genetic similarity of man and the anthropoid apes].