Cusp

... it be grouped with the original species, or with the resulting species, or as something else entirely? Many species today exist right on this cusp of a speciation event, and are called ring species. To put it very briefly, population A can interbreed with population B, which can interbreed ...

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... want to be an organ donor. Hospital staffs always ask permission before arranging for donations. --R.D.W. Sixty years ago, scientists were on the cusp of a revolutionary scientific breakthrough. In the preceding decades, researchers had had some success transplanting organs in animals, and there ...

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