The DNA legacy of the first human settlers of the Americas has started to paint a complex picture of multiple waves of migration and genetic variation.
Now it’s the many languages of America which are the latest clue to the earliest beginnings of people in the hemisphere, according to new work to be presented Friday at the annual meeting of the American Association for the Advancement of Science.
Languages without any familial connection to known dialects – called “isolates” – exist in large numbers running down from what was Beringia, south along the western edge of the two continents. Twenty-six isolates are in North America, and 55 exist in South America, according to the team of scientists.
“Scientists in the past few decades have rethought the settlement of the Americas,” said Mark Sicoli, the linguistic anthropologist at the University of Virginia who led the work.
The original theory that the last ice age created a “bridge” from Asia to North America that allowed a single wave of colonization has since become a stepping-stone for a more complex theory: that the ice age land mass known as Beringia was a waystation for settlement that lasted thousands of years, said Sicoli.
Sicoli and colleagues Anna Berge at the University of Alaska, and Gary Holton at the University of Hawaii took the indigenous languages in existence now, and used “big data” to recreate how they may have developed over time.
They found that there were at least three extinct languages that went into the linguistic melting pot, they report. These three or more fed into the evolution of the Dene and Aleut tongues that have survived to the modern day.
They found other migrations – and even back-migration returning to Asia among the Yeniseian speaking peoples of Siberia.
This was done through cataloging the dialects from three continents, combining maps and language networks, they write.
“Based on linguistic analysis including computations phylogenetics, we suggest the prehistory of South Alaska, the Aleutian Islands, and the Pacific Northwest Coast involved intensive language contacts, including language shifts from now extinct languages that we can infer through typological features, grammar and vocabulary found in languages documented in historic periods,” they add.
Major breakthroughs in DNA of the New World’s first settlers were made in 2015. A Harvard team led by geneticist David Reich found that multiple waves of settlers, including some who share genes with peoples from South Asia and Australia, settled the Americas. The “Beringian standstill model” was further elucidated that same year by a University of Utah team that explored the mitochondrial DNA of two infants that were buried 11,500 years ago. Also, that same year, the famed “Kennewick Man” found near the banks of the Columbia River in 1996, where he had fallen and died some 9,000 years earlier, was connected genetically to Native Americans in the same area of the Pacific Northwest.