Norwegian lemmings are a unique species according to a new analysis of lemming DNA conducted by researchers at the Swedish Museum of Natural History that was published n the March 24, 2014, issue of the journal Molecular Ecology.
The researchers compared the DNA of fossil Norwegian lemmings, modern Norwegian lemmings, and all species of ancient and modern lemmings found in the Scandinavian Peninsula, Finland, Sweden, and Russia.
No species of lemming demonstrated a close enough match to the DNA of Norwegian lemmings to indicate that there were any ancient relatives of the Norwegian lemming except itself.
The previous presumption was that lemmings moved into Norway after the ice sheets melted during the last Ice Age about 20,000 years ago.
The evidence indicates that the Norwegian lemming was resident in Norway during the last Ice Age and managed to survive the extreme cold of that period. The researchers suggest that the lemmings in Norway may have moved to coastal areas or mountain regions that were not covered by ice in order to survive.
The conclusion correlates with the dramatic changes in the size of present populations of lemmings in Norway and may be the origin of the lemming’s population control behaviors. The large size of the Norwegian lemming compared to other species of lemming may be an evolutionary development that allowed the Norwegian lemming to survive.