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Species, concept of pure and impure breeds.

  1. Jun 8, 2014 #1
    The definition of species is "a group of organisms that can interbreed with each other". So, how is interbreeding of two dogs of different species, say a german shepherd and a pitbull, possible? And the concept of a "pure" and "impure" breed - how will you explain it? As according to the definition, a GSD cannot be crossed with a pitbull?!
  2. jcsd
  3. Jun 8, 2014 #2

    Simon Bridge

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    A breed is not the same thing as a species.

    German Shepherd and Pitbull are not different species, they are different breeds of the same species. The concept of pure and impure breeds refers to inherited characteristics of the breed and lineage (pedigree).

    A breed is a stock of animals or plants within a species having a distinctive appearance and typically having been developed by deliberate selection.

    More on species:
    http://evolution.berkeley.edu/evosite/evo101/VA1BioSpeciesConcept.shtml [Broken]
    Last edited by a moderator: May 6, 2017
  4. Jun 10, 2014 #3
    Also, your definition lacks precision. It could be improved thus:

    A species is a group of organisms that can interbreed with each other and commonly do so.

    Lions and tigers can interbreed yet are members of separate species, yet interbreeding is rare.
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