sentences:  However, without consulting the Dvůr Králové Zoo, the semen of a southern white rhino was used instead of a northern white rhino, which the zoo considers a wasted opportunity.Nevertheless, the experiment showed that viable hybrid embryos of the northern and southern white rhino are possible through IVF, as well as a path to the creation of pure northern white rhino embryos.The San Diego Zoo Safari Park in San Diego, California, had eight wild-caught northern white rhinos.