Genetic Study Tracks the First Hawaiians

STANFORD, CALIFORNIA—Science Alert reports that Alexander Ioannidis of Stanford University and his colleagues analyzed the genomes of more than 1,000 people who live in French Polynesia; 12 genomes from individuals on the island of Rapa Nui; and the genomes of people native to Hawaii, Samoa, Tonga, and Tahiti. First, the researchers isolated segments of Polynesian ancestry with machine learning, and then they applied an identity by descent method, which can identify common ancestors of living people and people from the past. The study shows that people traveled across Polynesia in small populations, sometimes resulting in a genetic bottleneck of reduced genetic variation that can increase the odds of the occurrence of harmful mutations known as the founder effect. People who became Native Hawaiians are thought to have experienced a series of bottlenecks as they traveled long distances on small double-hulled catamarans. “Hawaii is the only Polynesian island in the Northern Hemisphere, so it’s a long way from everything,” Ioannidis explained. The study also suggests that Native Hawaiians are most closely related to the people of Rapa Nui. The two islands are more than 4,000 miles apart, and each one is about 2,000 miles from another island. Both populations were also found to be related to people on Mangareva Island, which may have been their launching point in French Polynesia, Ioannidis concluded. For more on early Hawaiian history, go to “Letter from Hawaii: Inside Kauai’s Past.”