During historical glacial periods when large areas of land are covered by ice s…

During historical glacial periods when large areas of land are covered by ice sheets (ice ages), species distributions are fragmented into small disjunct areas that remain ice free. These are known as glacial refugia.
1. What evolutionary phenomena are the populations in the glacial refugia likely experiencing?
2. As the glaciers melt and species reestablish their previous distribution, what phenomena will the refugial populations experience?

1. What evolutionary phenomena are the populations in the glacial refugia likely experiencing?
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