I'm not convinced, and I find the sceptic quoted in the article's objection that the claimed similarities are all in words short enough to be chance to be a strong argument, but its still very interesting.
A linguistic adventurer chases down an ancient language in Siberia and discovers a surprising connection to modern languages in North America
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"All this" is Mr. Vajda's announcement of a linguistic link between Asia and the Americas, a discovery that has sent a wave of celebration — and controversy — through his field.
In 1987, Mr. Vajda was a new professor of Slavic Studies at Western Washington University in Bellingham, Washington, where he came across a book in Russian about a language called Ket, a nearly extinct language spoken by only 1,000 people in a remote area of central Siberia. It belonged to a language family called Yeneseic, of which Ket was the only survivor. One its siblings, Arin, is only known because a Cossack adventurer named Arzamas Loskutov wrote down words from the last Arin speaker in 1735.
Reading the book, Mr. Vajda noticed the Ket verbs, a complex string of particles attached to a root that make up almost an entire sentence. "It was intriguing," Mr. Vajda says, "because the verb is completely different from anything else in Asia." In fact, they reminded him of verbs in Navajo, a Na-Dene language that he had studied. That was enough to pique his interest to pursue evidence of a connection between Na-Dene and Yeniseian — a linguistic connection between Asia and the Americas.