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Comment on “Glacial Survival of Boreal Trees in Northern Scandinavia”

Parducci et al. (Reports, 2 March 2012, p. 1083) fail to present convincing evidence for glacial survival of Pinus and Picea in northern Scandinavia. Their methodology does not exclude contamination. Additionally, they should consider the lack of suitable habitats, the apparent extinction of both taxa after deglacial warming, and alternative hypotheses for the distribution of the Picea genetic marker haplotype A.