Revelations of ancient head shape: Cranial modification in the Cuzco region of Peru, Early Horizon to Inca Imperial Period.

OBJECTIVES: Cranial vault modification (CVM), the intentional reshaping of the head, indicated group affiliation in prehistoric Andean South America. This study aims to analyze CVM data from the Cuzco region of Peru to illuminate patterns of early migration and settlement along with the later impact of the Inca Empire (AD 1438-1532) on the ethnic landscape. MATERIALS AND METHODS: 419 individuals from 10 archaeological sites spanning over 2300 years were assessed for CVM using morphological analysis. RESULTS: CVM patterns show distinct temporal attributes: the tabular type of modification appeared first and dominated the early sample (900 BC-AD 600), followed by an influx of unmodified crania during the Middle Horizon (AD 600-1000). The annular type appeared later during the Late Intermediate Period (AD 1000-1438). In the subsequent period of Inca imperialism, modification rates were higher at sites in the Cuzco countryside than in Cuzco city sites. DISCUSSION: The study results, combined with archaeological and ethnohistoric data, reveal the sociopolitical transformations that occurred prior to and during the rise of the Inca Empire. The influx of unmodified crania during the Middle Horizon resulted at least partly from Wari occupation, while the appearance of the annular type during the LIP points to migration into the area, possibly from the Lake Titicaca region. In the Inca Imperial Period, Inca individuals at Cuzco city sites refrained from modification as a sign of their ethnic identity, while modification patterns in the Cuzco countryside likely reflect state-coerced resettlement of different ethnic groups.

Skeletal evidence for Inca warfare from the Cuzco region of Peru.

This article addresses the bioarchaeological evidence for Inca warfare through an analysis of 454 adult skeletons from 11 sites in the Inca capital region of Cuzco, Peru. These 11 sites span almost 1000 years (AD 600-1532), which allows for a comparison of the evidence for warfare before the Inca came to power (Middle Horizon AD 600-1000), during the time of Inca ascendency in the Late Intermediate Period (AD 1000-1400), and after the Inca came to power and expanded throughout the Cuzco region and beyond (Inca Imperial Period, AD 1400-1532). The results indicate that 100 of 454 adults (22.0%) showed evidence of cranial trauma. Of these, 23 individuals had major cranial injuries suggestive of warfare, consisting of large, complete, and/or perimortem fractures. There was scant evidence for major injuries during the Middle Horizon (2.8%, 1/36) and Late Intermediate Period (2.5%, 5/199), suggesting that warfare was not prevalent in the Cuzco region before and during the Inca rise to power. Only in the Inca Imperial Period was there a significant rise in major injuries suggestive of warfare (7.8%, 17/219). Despite the significant increase in Inca times, the evidence for major cranial injuries was only sporadically distributed at Cuzco periphery sites and was entirely absent at Cuzco core sites. These findings suggest that while the Inca used warfare as a mechanism for expansion in the Cuzco region, it was only one part of a complex expansion strategy that included economic, political, and ideological means to gain and maintain control.

Trophy-taking and dismemberment as warfare strategies in prehistoric central California.

We document evidence for trophy-taking and dismemberment with a new bioarchaeological database featuring 13,453 individuals from prehistoric central California sites. Our study reveals 76 individuals with perimortem removal of body parts consistent with trophy-taking or dismemberment; nine of these individuals display multiple types of trophy-taking and dismemberment for a total of 87 cases. Cases span almost 5,000 years, from the Early Period (3000-500 BC) to the Late Period (AD 900-1700). Collectively, these individuals share traits that distinguish them from the rest of the population: a high frequency of young adult males, an increased frequency of associated trauma, and a tendency towards multiple burials and haphazard burial positions. Eight examples of human bone artifacts were also found that appear related to trophy-taking. These characteristics suggest that trophy-taking and dismemberment were an important part of the warfare practices of central Californian tribes. Temporally, the two practices soared in the Early/Middle Transition Period (500-200 BC), which may have reflected a more complex sociopolitical system that encouraged the use of trophies for status acquisition, as well as the migration of outside groups that resulted in intensified conflict. Overall, trophy-taking and dismemberment appear to have been the product of the social geography of prehistoric central California, where culturally differentiated tribes lived in close proximity to their enemies.

The causes of porotic hyperostosis and cribra orbitalia: a reappraisal of the iron-deficiency-anemia hypothesis.

Porosities in the outer table of the cranial vault (porotic hyperostosis) and orbital roof (cribra orbitalia) are among the most frequent pathological lesions seen in ancient human skeletal collections. Since the 1950s, chronic iron-deficiency anemia has been widely accepted as the probable cause of both conditions. Based on this proposed etiology, bioarchaeologists use the prevalence of these conditions to infer living conditions conducive to dietary iron deficiency, iron malabsorption, and iron loss from both diarrheal disease and intestinal parasites in earlier human populations. This iron-deficiency-anemia hypothesis is inconsistent with recent hematological research that shows iron deficiency per se cannot sustain the massive red blood cell production that causes the marrow expansion responsible for these lesions. Several lines of evidence suggest that the accelerated loss and compensatory over-production of red blood cells seen in hemolytic and megaloblastic anemias is the most likely proximate cause of porotic hyperostosis. Although cranial vault and orbital roof porosities are sometimes conflated under the term porotic hyperostosis, paleopathological and clinical evidence suggests they often have different etiologies. Reconsidering the etiology of these skeletal conditions has important implications for current interpretations of malnutrition and infectious disease in earlier human populations.

Prehistoric trepanation in the Cuzco region of Peru: a view into an ancient Andean practice.

In this study, patterns of prehistoric trepanation in the southern highlands of Peru were examined through an analysis of 11 Cuzco-region burial sites. Trepanations were found in 66 individuals, with several individuals exhibiting more than one trepanation, for a total of 109 perforations observed. The predominant methods used were circular cutting and scraping-methods that proved highly successful with an overall 83% survival rate and little ensuing infection. Survival rates showed a significant increase over time, apparently reflecting improvements in trepanation technique through experimentation and practical experience. Practitioners avoided certain areas of the cranium and employed methods that reduced the likelihood of damage to the cerebral meninges and venous sinuses. In many cases, trepanation as a medical treatment appears to have been prompted by cranial trauma, a finding that corroborates other studies pointing to cranial trauma as a primary motivation for the surgical procedure.

Bioarchaeological evidence for trophy-taking in prehistoric central California.

Fourteen adult burials in a large (N = 224) prehistoric central California cemetery (CA-SCL-674) lack forearm bones. Twelve of these otherwise well-articulated primary interments have distal humeri bearing cutmarks with a distribution like that seen in fur seals butchered by Native Californians. Most of the burials with missing forearms are young adult males, a demographic profile that differs significantly from the full sample. Three of these males show evidence of perimortem trauma in addition to forearm amputation. Drilled and polished human radii and ulnae were recovered from the CA-SCL-674 cemetery in archaeological contexts separate from burials with missing forearms. A warfare-related trophy-taking practice is strongly suggested by these bioarchaeological data. Based on these data, it seems likely that 20% (N = 10) or more of the adult males (N = 59) in this population were victims of violence. Evidence of perimortem violence was much less common among women, with only about 2% (N = 2) of adult females (N = 86) subjected to trophy-taking. Examination of museum collections produced further evidence for perimortem forearm amputation among the Native American inhabitants of this area during the transition between the Early and Middle periods. The emergence of more hierarchical social systems during this period may have fostered warfare-related trophy-taking as a symbolic tool for enhancing the power and prestige of individuals within competing social groups.