Page "Red Knot" Paragraph 11

Studies based on mitochondrial sequence divergence and models of paleoclimatic changes during the glacial cycles suggest that canutus is the most basal population, separating about 20, 000 years ago ( 95 % confidence interval: 60, 000 – 4, 000 years ago ) with two distinct lineages of the American and Siberian breeders emerging about 12, 000 years ago ( with a 95 % confidence interval: 45, 000 – 3, 500 years ago ).