Everyone agrees that Homo sapiens is a different species (and most would say a different genus) from Pan troglodytes, the chimpanzee. But everyone also agrees that if you follow human ancestry backward to the shared ancestor and then forward to chimpanzees, the intermediates all along the way will form a gradual continuum in which every generation would have been capable of breeding with its parent or child of the opposite sex. By the interbreeding criterion every individual is a member of the same species as its parents. This is an unsurprising, not to say platitudinously obvious conclusion,
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