Analyses of ancient DNA from prehistoric humans paint a picture of dramatic population change in Europe from 45,000 to 7,000 years ago, according to a new study led by Howard Hughes Medical Institute Investigator David Reich at Harvard Medical School.
The new genetic data, published May 2, 2016 in Nature, reveal two big changes in prehistoric human populations that are closely linked to the end of the last Ice Age around 19,000 years ago. As the ice sheet retreated, Europe was repopulated by prehistoric humans from southwest Europe (e.g., Spain). Then, in a second event about 14,000 years ago, populations from the southeast (e.g., Turkey, Greece) spread into Europe, displacing the first group of humans.