>We sequenced complete mitochondrial genomes (mitogenomes) from 71 archaeological dog remains collected in North America and Siberia (Fig. 1a; Table S1) and an

>We sequenced complete mitochondrial genomes (mitogenomes) from 71 archaeological dog remains collected in North America and Siberia (Fig. 1a; Table S1) and analyzed these with 145 mitogenomes derived from a global dataset of modern and ancient canids (3). A phylogenetic tree constructed from the mitogenomes indicated that all sampled pre-contact dogs (spanning ~9,000 years) formed a monophyletic group within dog haplogroup A (Fig. 1b; Fig. S3; Fig. S6), which we refer to as pre-contact dogs (PCD). This analysis indicated that the most closely related mitochondrial lineage to the PCD clade are ~9,000 year-old dogs from Zhokhov Island in Eastern Siberia (3) (Fig. 1b; Fig. S3; Fig. S6). In addition, molecular clock analyses suggest that all PCD dogs shared a common ancestor ~14,600 years ago (95% high posterior density [HPD]: 16,484- 12,965; Fig. 1b; Fig. S6), which diverged from a shared ancestor with the Zhokhov Island dogs ~1,000 years earlier (95% HPD:17,646-13,739; Fig. 1b; Fig. S6). Interestingly, these time frames are broadly coincident with early migrations into the Americas (10–12).[0] Population genetics / migration can get quite complicated (different waves etc.) but the bottom line is all pre-contact dogs (meaning before the European colonists came) share a common ancestor @ 14,600 BC which in turn diverged from a shared ancestor with the Zhokhov Island [Siberia] dogs ~1,000 years earlier. >The history of the global dispersal of dogs remains contentious (1). In North America, the earliest confirmed dog remains have been radiocarbon dated to ~9,900 calibrated years before present (cal BP) (Koster, Illinois; (2, 3)), approximately 6,000 years after [!] the earliest unambiguous evidence of humans arriving in North America (4). While these early dogs were most likely not domesticated in situ [i.e. from North American wolves] (5), the timing of their arrival and their geographic origins are unknown [!]. [0]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7116273/figure/F1/?report=objectonly https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7116273/figure/...