The recent rekindling of this debate involves the genome sequencing of a small boy that lived approximately 12,600 years ago. The boy, approximately 1-2 years old at the time of his death, is believed to be one of the Clovis people - a group that inhabited significant areas of North America during this time period, but basically vanished shortly thereafter. Tools indicative of the Clovis culture were found in the burial site along with the boy, thus the boy is assumed to be one of the Clovis people - and he represents the only human skeletal remains ever found with Clovis tools. The site, known as the Anzick site, is located near Wilsall, Montana.
After DNA analysis, the researchers were able to conclude that approximately 80% of all modern-day Native American populations are directly descended from the family of the Clovis boy, and the remaining 20% have more genetic similarities with the Clovis boy than they do with any other people on Earth. In turn, the Clovis boy, along with all present day Native Americans, share around one-third of their genes with previously analyzed 24,000 year old skeletal remains found in Siberia.
Advocates of the theory of Siberian descent suggest that humans probably migrated from Siberia to Beringia sometime between 26,000 and 18,000 years ago. Ancient Beringia is an area consisting of northeast Russia, parts of Alaska, and the area in between (at one time a land mass, but now covered by the Bering Sea). Glacier movement cleared the way for these humans to cross the Bering Strait and disperse throughout the Americas, splitting into groups. Some headed to modern day Canada, others dispersed throughout Mexico, Central and South America, and still others dispersed throughout North America - including the ancestors of the Clovis people.
Not so fast, say the Solutrean advocates. They point out that other artifacts found buried with the Clovis boy predate his death by centuries, including stone spear points and elk antlers. This would seem to imply that these were precious heirlooms that were handed down over many generations. Similar artifacts have been dated to 20,000 years old, predating the supposed arrival of migrants from Beringia, and have a resemblance to Solutrean artifacts.
Further, mitochondrial DNA in Native Americans has been linked to western Eurasia but not to eastern Eurasia, where those migrating across Beringia would have originated. How else did the mitochondrial DNA arrive if not through migration?
An even more interesting question is: what is the significance of the burial site containing the boy and all of these artifacts? Is it meaningful, or a case of anthropological misdirection? More evidence is likely to come over the years, but the only thing we can conclude for sure regarding this discovery is that anthropologists love a good debate.