Abstract: After a long period of static species concept, followed modern times with new technologies of investigations and wider vision of most systematists who accepted the dynamic species outlook. Adopting population thinking, it was also accepted importance of intra- and interpopulation variation due to geographical and other forms of isolation. The key words - reproductive isolation are referring to the way of a community or part of a population are becoming genetically very different from other populations; it is so called genetic incompatibility of interbreeding. Thus, appeared the meaning of biological species concept (BSC). Because deep differences arise in a long time........
Key words: species, speciation, reproductive isolation, genetic variability, evolution
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