REYKJAVIK, ICELAND—According to a report in Science Magazine, a new genetic study of Icelanders led by S. Sunna Ebenesersdóttir of the University of Iceland suggests the population rapidly shifted from a roughly even mix of Norse and Gaelic ancestry some 1,000 years ago, to mostly Norse ancestry today. The team analyzed genomes obtained from 27 ancient skeletons found across Iceland, and found that these early settlers of the island had genes associated with populations from Norway, Sweden, Ireland, and Scotland. The researchers then used a computer simulation to model the change to predominantly Norse ancestry, and found evidence for genetic drift, or random fluctuations in gene frequencies, which has been seen in isolated populations of animals. The study notes that recent immigration from Scandinavia, and especially from Denmark, also had an impact on Iceland’s gene pool. The scientists note that those settlers with Gaelic ancestry were likely to have been enslaved, giving those with Norse ancestry a reproductive advantage. In addition, the enslaved may have been buried in unmarked graves, possibly leaving them underrepresented in the test sample. To read in-depth about a mysterious site in Iceland, go to “The Blackener’s Cave.”