Cultural relationships between historic Baja California Sur indigenous groups are poorly understood, despite the presence of historical accounts of these peoples. Relationships between groups largely have been reconstructed through linguistic attributes recorded by Jesuit missionaries. Non­linguistic cultural traits derived from historical accounts also can be used to determine relationships between groups. We use content analysis to systematically organize cultural trait information from historical explorer accounts, Jesuit missionary documents, and academic research pertaining to three Lower California groups: the Pericú, Guaycura, and southern Cochimí, as well as the Seri/Comcáac Indians of the Gulf of California and Sonora. Reliability analyses reveal considerable cultural homogeneity between the southern Cochimí and Guaycura, and cultural dissimilarity between all other groupings. Hierarchical cluster analysis reveals the Guaycura and southern Cochimí comprise a distant, but natural grouping with the Seri/Comcáac, while the Pericú are isolated. Several hypotheses are presented to explain these patterns.

How and when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we found that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (ka) and after no more than an 8000-year isolation period in Beringia. After their arrival to the Americas, ancestral Native Americans diversified into two basal genetic branches around 13 ka, one that is now dispersed across North and South America and the other restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians (including Siberians) and, more distantly, Australo-Melanesians. Putative "Paleoamerican" relict populations, including the historical Mexican Pericúes and South American Fuego-Patagonians, are not directly related to modern Australo-Melanesians as suggested by the Paleoamerican Model.

How and when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we found that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (ka) and after no more than an 8000-year isolation period in Beringia. After their arrival to the Americas, ancestral Native Americans diversified into two basal genetic branches around 13 ka, one that is now dispersed across North and South America and the other restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians (including Siberians) and, more distantly, Australo-Melanesians. Putative "Paleoamerican" relict populations, including the historical Mexican Pericúes and South American Fuego-Patagonians, are not directly related to modern Australo-Melanesians as suggested by the Paleoamerican Model.