Datasets S1 from Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic

Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but whether the Inuit adopted local Paleo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Paleo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Paleo-Inuit dogs, and most likely aided the Inuit expansion across the North American Arctic beginning around 1000 BP.

在北美洲北极地区，家犬自古以来便居于生活核心。爱斯基摩人的先祖是首批将狗拉雪橇运输技术广泛引入美洲的群体，然而，爱斯基摩人是采纳了当地的古爱斯基摩犬，还是引入了新的犬种群体至该地区，这一问题至今仍无定论。为验证这些假说，我们收集了922只北美北极地区犬类和狼类的线粒体DNA以及头骨和牙齿元素的几何形态计量数据，时间跨度超过4500年。我们的分析揭示，公元前2000年以来的因纽特人遗址中的犬类，其形态学和遗传特征与早期古爱斯基摩犬存在显著差异，并在西伯利亚东部和阿拉斯加识别出一个新的线粒体分支。尽管在考古学上的北极犬与现代北极犬在表型上存在差异，但这些因纽特犬的遗传遗产在今天仍存活于现代北极雪橇犬中。综合我们的数据，揭示因纽特犬源自一次与古爱斯基摩犬不同的次级接触前犬类迁移，且最有可能在公元前1000年左右帮助因纽特人扩张至北美北极地区。