Datasets S3 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.

自古以来，家犬便在北美北极地区的生活中占据核心地位。爱斯基摩人的先祖是首个将狗拉雪橇运输技术广泛应用于美洲的群体，然而，爱斯基摩人是采纳了当地的古爱斯基摩犬种，还是引入了新的犬种至该地区，这一问题至今未解。为验证这些假说，我们对来自北美北极地区的922只犬和狼的颅骨及牙齿元素进行了线粒体DNA及几何形态测量数据的采集，时间跨度超过4500年。我们的分析揭示，公元前2000年以来的因纽特犬种在形态学和遗传特征上与早期的古爱斯基摩犬种存在显著差异，并在西伯利亚东部和阿拉斯加地区识别出一个新的线粒体谱系。尽管考古学上的北极犬与现代北极犬在表型上存在差异，这些因纽特犬的遗传遗产至今仍存在于现代的北极雪橇犬中。我们的数据共同表明，因纽特犬源自一次独立的、与古爱斯基摩犬种不同的二次接触前的犬种迁移，且很可能在公元1000年左右帮助因纽特人扩张至北美北极地区。