section_path: Definition/Mayr's biological species concept
section_name: Mayr's biological species concept
paragraph_text: Mayr's biological species concept
  
  Most modern textbooks make use of Ernst Mayr 's 1942 definition, known as the Biological Species Concept as a basis for further discussion on the definition of species. It is also called a reproductive or isolation concept. This defines a species as
  
  groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.
  
  It has been argued that this definition is a natural consequence of the effect of sexual reproduction on the dynamics of natural selection. Mayr's use of the adjective "potentially" has been a point of debate; some interpretations exclude unusual or artificial matings that occur only in captivity, or that involve animals capable of mating but that do not normally do so in the wild.