According to National Geographic, researchers used ancient and mitochondrial DNA, which is passed down only from mothers to daughters, to estimate that the Native American population was at its highest about 5,000 years ago.
The population then dips to its lowest about 500 years ago, a few years after Christopher Columbusarrived and before European colonization began.
Brendan O’Fallon, co-author of the study, thinks many of the earlier casualties were the cause of disease, which “would likely have traveled much faster than the European settlers themselves.”
In good news, O’Fallon, a population geneticist who conducted the study while at the University of Washington, said Native American population numbers have bounced back and the group’s genetic health didn’t suffer any long-term damage.
“Our study did not find a substantial reduction in genetic diversity,” O’Fallon told National Geographic. “The bottleneck was fairly short-lived and, while significant, didn’t appear to eliminate many lineages that were present before Europeans arrived.”