This happens in nature, actually. When there's a genetic disparity between individuals, although offspring is possible, it ends up infertile. That's nature's wa

This happens in nature, actually. When there's a genetic disparity between individuals, although offspring is possible, it ends up infertile. That's nature's way of doing a U-turn. When the hybridization is managed by humans though, it can be useful (e.g.: citrus, mules).