The theoretical concept of the biological species as a reproductive community

Abstract

The biological species concept of the reproductive community is examined with regard to consequence and consistency, and it is found that the conditions under which the organisms belonging to a reproductive community can successfully reproduce are not clearly defined. The widespread concept that the mating barriers between two different species are tight, so that successful mating between two species would show that they are not two different species, is not tenable. Hybridizations between different species are common and in certain cases can even be essential for the survival of the species and in some examples also lead to the emergence of a new species. It is further stated that the term “species” is neither a reality that exists beyond of human thinking “out there in nature”, nor can the finding of a universal concept for the term “species” be successful.