Fig. 1. Genetic sourcing of traded artifacts back to specific walrus stocks.

The Bayesian phylogeny includes walrus mitogenomes from 100 biological samples and 31 cultural artifacts. These biological samples were obtained from a wide range of geographic locations and chronological periods to reconstruct genetic diversity and stock locations at the time of the Norse Greenland settlements. Our results confirm that distinct walrus stocks were located in specific locations (Fig. 2 and table S1). This combined approach enabled the walrus artifacts recovered from trade and production centers in Europe and the main Greenland Norse settlements to be genetically sourced back to specific walrus stocks and particular Arctic hunting grounds (Fig. 2 and table S2). The phylogeny is rooted against the Pacific walrus (not shown). Black circles denote nodes with >90% posterior support. Figure: E.J.R.-P. and coauthors.