Another curious Solithromycin in the history of P. pumila is the surprisingly early age (∼9600 14C/∼11,100 cal yr BP) for the shrub\'s presence in the Chukchi Upland. Modern pollen samples demonstrate that P. pumila is not as over represented as other Pinus taxa (likely due to its large size; Lozhkin et al., 2001). Furthermore in the case of the large-diameter Lake El\'gygytgyn, the pollen catchment appears to be from the surrounding Upland, and it is unlikely the core is overly influenced by long distance pollen rain from such areas as Eastern Siberia ( Matrosova, 2006 and Lozhkin et?al., 2007). Additionally, there is the question of the source of the Pinus pollen. Evidence exists for the survival of Larix, which shares similar summer temperature requirements as P. pumila, during the LGM in the northern coastal lowlands of Western Beringia, but pollen data do not suggest altitudinal gradient P. pumila was also present ( Anderson et al., 2002). However, plant macrofossils from the lower Indigirka River indicate the presence of P. pumila, L. gmelinii, Picea, and tree Betula by ∼10,000 14C/∼11,400 cal yr BP (Lozhkin et al., 2011a). Although other data exist supporting treed vegetation in coastal areas of Western Beringia (see Section 7.2.2.), no other sites have been found with P. pumila macrofossils. However, the paleobotanical data are suggestive of a northern source of P. pumila for the El\'gygytgyn area and a separate southern source for the Kankaren region.
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