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If you recreated intermediate species between every species on the evolutionary tree, would every species be able to reproduce with each other through a series of intermediates? Would this blur the concept of "species"?


marked as duplicate by Remi.b, Community Sep 25 '16 at 15:09

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    $\begingroup$ Yes it is a concept like Fuzzy logic. It exists but its 'border' is not at all clear cut. $\endgroup$ – Always Confused Sep 25 '16 at 13:33
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    $\begingroup$ Like your head-hairs and beards can-not be distinguished with 1 clear-cut line; yet your head-hair and beard is not the same; they have some own features... beards grow-up only on and after adolescence. $\endgroup$ – Always Confused Sep 25 '16 at 13:37
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    $\begingroup$ 'reproductive barrier' is a main, but not the only criterion to define a species. It is used mostly for the animals. In case of other-kingdoms; only vegetatively reproducing strains, reproductive isolation could not be judged. Rather we have to depend on other sorts of characteristics; from macroscopic through biochemical to molecular-genetic. In certain cases, especially for microbes, to define a species is really difficult; and sometimes instead species, directly the specimen-number ( like certain particular collection-number or culture number) is preferred. $\endgroup$ – Always Confused Sep 25 '16 at 13:44
  • $\begingroup$ Without need to recreate any species, en.wikipedia.org/wiki/Ring_species offers a real life examples of the situation proposed by the OP. It challenges the concept of species somehow, but also sheds light on the process of speciation. $\endgroup$ – Pere Jan 26 at 23:54

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