Comment on “Glacial Survival of Boreal Trees in

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. Parducci et al. (1) propose thatPicea (spruce)and Pinus (pine) survived the Last GlacialMaximum (LGM) in northern Scandinavia, based on the amplification of ancient chloroplast DNA (cpDNA) in lake sediments fromEndletvatn on the Andøya strandflat, northwest Norway (69°N) and genetic evidence from extant spruce populations. We comment first on their method-ology and then on their interpretations. (i) How reliable is ancient DNA (aDNA) from lake sediments? Although knowledge of aDNA, in-cluding sedimentary aDNA (sedaDNA), and envi-ronmental DNA is advancing rapidly, Hofreiter et al