Expansion of the house mouse in the North Atlantic area in the Iron Age - Roman period, Viking Period and 'Modern' era based on mtDNA sequences. Colours for the mtDNA clades are the same as in Figure 2, which depicts the current distribution of the clades. The M. m. musculus/M. m. domesticus hybrid zone is marked with a black line. The mice that originally colonized Greenland in the Viking era may have gone extinct; only mice of the Danish colonization have been found there now.
Jones et al. BMC Evolutionary Biology 2012 12:35 doi:10.1186/1471-2148-12-35