So, I linked to an article a few days ago talking about the pole-ward migration of species. This is one of the results of that, namely that there is going to be a loss in genetic diversity. As the climate changes, species move, if their movement is restricted by say living in a stream that doesn't go in the right direction, they die. Maybe not the whole species, but certainly a decent chunk of it can be at danger. And a lack of diversity within a species is not going to help a species adapt to further changes in climate. We are going to lose so much in the next century or so. sigh.