In the exceptionally cold winter of 1997, lake superior froze over between the wisconsin mainland and isle royale. A pack of 8 wolves crossed the ice and reached isle royale, an island where they encountered a population of about a dozen wolves. It is estimated that the wolf population on isle royale had been isolated for over 100 years (~10 generations). If the 8 wolves could not successfully interbreed with the island population, which species concept would classify the two populations as separate species?.