The complete mitochondrial cytochrome b genes from four ground squirrels, a marmot, and a tree squirrel were sequenced and compared. A level of divergence three times lower than expected based on fossil evidence was found between the marmot and the ground squirrels. The observed divergence was similar to that found within the ground squirrels and is consistent with a recent divergence of marmots (Marmota) from true ground squirrels (Spermophilus).
