... and soon they cannot interbreed, hence becoming a new species. Species “A” Geographically Isolated Permanent Isolation - Bodies of water - Mountain formation - Volcanic activity - Destruction by man New Species A good example of allopatric speciation is the differences between the common giraffe (Giraffa camelopardalis), and the reticulated giraffe (Giraffa cameloparadalis reticula). These two subspecies have formed on different sides of the Tana River in Kenya. They are phenotypically distinct, and can only produce fertile offspring in zoos. Sympatric speciation occurs when two segments of the same species occupy a geographical area without interb ...