Field Report: Materials from the Cave of Lost Causes
Archaeological Research Facility
THE PREHISTORY OF THE GUAYCURA IN BAJA CALIFORNIA SUR, MEXICO: EXCAVATIONS AT THE CAVE OF LOST CAUSES
Stahl funds were used to continue analysis and curation of the 2008 Cueva Santa Rita archaeological collection. Archeological collections excavated in the country of Mexico cannot leave the country, even temporarily. To finish the analysis phase of this dissertation project, considerable time was spent examining artifacts in Baja California Sur. By funding travel to Mexico, Stahl funds also made it possible to export ancient DNA samples for analysis at the University of Copenhagen and collect data for a poster presentation at the 2011 SAA meetings.
Curation and Artifact Analysis
Several months were spent in La Paz with the collection. Analysis included classification of cordage (dm, length, spin, twist, twist per cm., angle of twist, wear); debitage (unit, quad, level, material, weight aggregate analysis, size aggregate analysis, tripel cortex analysis, free standing typology); cores (size, wt., type, use wear), olivella shell beads and bead blanks (shell type circumference size, height, #of ground surfaces, shape of spire, cordage present, # of suture lines, surface wear, heat treatment); projectile points (length, width, In addition all data was digitized and photographs were taken of nearly every artifact. Permission was received to store the collection at a facility in La Paz.
Permission was also received to export “contact” DNA samples for DNA analysis and extraction of mtDNA at the Center for GeoGenetics. Samples include a reed skirt fragment, corn, quid, and coprolites. Samples were hand carried to the United States and mailed to Copenhagen.
Significance of mtDNA analysis
A long-debated concept regarding southern Baja California prehistory involves its population history, with particular attention focused on antiquity of the Pericú in the southernmost portion of the peninsula. Although the aDNA laboratory at the Centre for GeoGenetics has extracted aDNA from Pericú burials in the Cape Region, to understand population dynamics in the southern peninsula, it is crucial to capture the spatial patterning of mtDNA lineages throughout the region. Given that the unique Pericú-style burials are found as far north as the central peninsula, many archaeological sites much farther north may be Pericú or ancestral Pericú.
The samples provided are from the Guaycura region, directly north and adjacent to the historically drawn boundaries of the Pericú. Data collection in this region was partially inspired by the discovery of Pericú-style burials in central Baja and survey work in the 1950’s that indicate Pericú territory may have been more extensive in the past. Our interest in the Pericú of the Cape Region is related to the potential for genetic and/or cultural isolation for an unusually long period of time, possibly as early as the Pleistocene. Early explorers and missionary accounts, some separated by decades, describe the southern Baja natives as being both physically and culturally different from other Native Americans. Recently, a systematic analysis of cultural traits (e.g. child carrying devices, female dress, male headdress, marriage patterns) discussed in these historic texts suggests the Pericú were culturally distinct from the Guaycura and Cochimí during the period of historic contact (Macfarlan and Henrickson 2010). However, this does not speak to the antiquity of the Pericú or the history of their relationships with the Guaycura, as cultural mechanisms can cause groups to diverge quickly, especially when population sizes are small (Neiman 1995). Archaeological sites have uncovered an interesting set of artifacts reminiscent of early sites in North America, including the retention of atlatls (Laylander 2007), projectile point production and styles (Aschmann 1952, Des Lauriers 2006; Des Lauriers 2008; Gutierrez and Hyland 2002), and notable absence of indigenous pottery (Massey 1966). Gonzalez-José et al. made headlines in 2003 when they published an article based on craniometric evidence stating skeletons from the Cape Region were most similar to Paleoamerican remains, attributing climate changes during the middle Holocene as restricting gene flow to the southern peninsula. Although many lines of evidence have suggested that southern baja populations may indeed be a remnant population of one of the earliest migrations into the New World, none are considered conclusive.
The results of cordage analysis were presented as a poster at the 2010 SAA meetings.
The goal of cordage analysis was to answer several questions:
1) Can we identify cordage attribues as characteristic of Cueva Santa Rita? Do cordage attributes vary by facies?
2) Can results of our analysis be used to interpet cultural relationships between sites and groups of sites?
I would like to thank the Stahl committee for the funding provided and the time and effort given to provide this opporunity to graduate students. The funding is very much appreciated and needed.