How populations can become isolated...

Populations in the world can become isolated in mnay ways. The first reason is that because of the climate. Some people like places that are cold;others like places that are warm and sunny with beaches at the coast. Many poeple like hot, sunny places because of the beaches. Thats why there are many populations that are isolated from one another. The second reason is maybe because of race. Many poeple don't like to live in a place with too much asians or mexicans so they move to a place where more of their race is common. That is why there is population isolation.