They may not have raped and pillaged, but "Viking" mice
conquered the outer reaches of the British Isles all the same.
Rodents living in Wales, Scotland and Ireland can trace their
ancestry to Norwegian house mice, presumably stowaways on Viking
ships. Because grain-eating house mice - Mus musculus domesticus
- depend on dense human populations, they serve as a reliable
proxy for human settlement and migration, says Jeremy Searle, an
evolutionary biologist at the University of York, UK, who led
the new study. "It's just a completely different angle to look
at and potentially add new pieces of evidence that historians
and archaeologists can use," he says. The discovery that mice
made the journey to the northern and western British Isles at
the time of the Vikings isn't much of a surprise in itself. The
Orkney Islands served as a major Norwegian Viking settlement in
the 11th and 12th centuries, and rodents probably sailed between
Scandinavia and Scotland. What surprised Searle's team was the
difference in mitoc