Suppose a single continent is breaking apart due to divergent plate boundary. One piece of the continent is moving north towards the polar regions and one piece of the continent is moving south towards the tropics. What effect do you think this process would have on biodiversity?
There is an increase in biodiversity due to the isolation that occurs and the adaptation that species must have to new habitat conditions. In the same way the species of each of the parts of the continent will be different from each other.