Ancient DNA discovery adjusts timeline of first North American humans: new study

Researchers examining ancient DNA have narrowed down the timeline of early human migration into North America — shedding light on a question that’s puzzled scientists for decades.The study, published online ahead of its appearance in the December 2026 issue of the journal Current Opinion in Genetics & Development, looked at previously published genetic and archaeological evidence to better understand when humans first arrived in the Americas.Genetic evidence most strongly supports humans reaching the Americas between 14,000 and 20,000 years ago, the study suggests — with an arrival before 15,000 years ago considered likely.Previously, scientists thought the first humans arrived in North America roughly 13,500 years ago, a theory known as “Clovis First.”Later archaeological discoveries have challenged that timeline, suggesting humans may have reached North America thousands of years earlier.The researchers, led by Bethany Potter and Savannah Hay of the University of Kansas, reviewed existing ancient DNA and archaeological evidence, including 23,000-year-old human footprints found at White Sands National Park in New Mexico.The footprints suggest humans may have inhabited North America earlier than the timeline supported by currently available genetic evidence.Such early populations could have belonged to genetic lineages that have not yet been sampled or that left no surviving descendants, the researchers said. By comparing previously published genetic data from ancient human remains in Asia and the Americas, researchers examined shared ancestry to trace how early Indigenous populations split into distinct groups.Some ancestral lineages diverged roughly 21,000 years ago, according to the review.The researchers also highlighted evidence that ancestral Native American populations split into northern and southern groups roughly 15,500 years ago, likely south of the massive ice sheets that once covered much of North America.That would mean their ancestors h...