First Americans May Have Taken A Coastal Route To Cross Over From Eurasia: Study

Tracing the journey of the first Americans is tricky, but new evidence supports the theory of the people taking the coastal route to the continent.

While the traditional theory was that early Americans got into the continent through Canada, there have been a number of research that show that this might not be the case. Instead, Alaska's southern coastline may have been the entry point.

A new study, published in the journal Science Advances on May 30, offers a glimpse at exactly how it's possible that early settlers entered Americas through the coast thousands of years ago.

Coastal Route Open To Humans

A team of researchers, led by the University at Buffalo, analyzed boulders and bedrock, found that a section of the coastal migration route in Alaska's Pacific border was actually accessible to humans as far back as 17,000 years ago.

Using surface exposure dating, the scientists discovered that the Alexander Archipelago — which used to be blanketed by glaciers — have been free from ice for 17,000 years, making it possible for human migration to take place.

Recent studies have suggested that settlers have been potentially exploring the Americas about 16,000 years ago, just after the gateway became accessible.

"Our study provides some of the first geologic evidence that a coastal migration route was available for early humans as they colonized the New World," first study author Alia Lesnek, a UB geology PhD candidate, explains in a statement. "There was a coastal route available, and the appearance of this newly ice-free terrain may have spurred early humans to migrate southward."

The bones of an ancient 17,000-year-old ringed seal have been previously found in a cave nearby, which means that humans can survive with the resources in the region.

Study: Not Conclusive Of The Actual Route

The study shows that human migration via Alaska's southern coastline is possible, but since the researchers only examined one part of the coast, it doesn't mean that early settlers really did go this way. Further examinations of other locations of the coast are necessary.

"Our research contributes to the debate about how humans came to the Americas," lead scientist Jason Briner, PhD, a professor of geology at UB's College of Arts and Sciences, says. "It's potentially adding to what we know about our ancestry and how we colonized our planet."

Why A Coastal Migration Is Likely

Initial belief of the early humans' journey to the Americas involved a route that went from Siberia to Canada, passing by an ice-free corridor in the middle of two ice sheets over 14,000 years ago. However, Briner points out that research has shown that this region only developed sufficient biological diversity that can support human life 13,000 years ago.

Archaeological studies have suggested that humans were already in Chile at least 15,000 years ago. There have also been evidence of human life in Florida as far back as 14,500 years in the past.

With these data and the new findings in mind, the coastal theory is not only feasible, but also likely due to the timing of the route's availability.