Looking back, looking forward: Paleopathology in Andean South America.

Over the past twenty years, the field of Andean paleopathology has advanced significantly thanks to a new generation of scholars who have been attracted to this region and whose innovative research has expanded our knowledge substantially. The papers in this special issue demonstrate how the field of Andean paleopathology has diversified and grown to become what is today a truly interdisciplinary enterprise involving archaeology, ethnohistory, biological anthropology, geochemistry, medical imaging, and genetics. These studies apply theoretical approaches to research questions that are increasingly innovative and nuanced as well as analytical methods that were in their infancy when I wrote my 1997 survey of the field.

A mass sacrifice of children and camelids at the Huanchaquito-Las Llamas site, Moche Valley, Peru.

Here we report the results of excavation and interdisciplinary study of the largest child and camelid sacrifice known from the New World. Stratigraphy, associated artifacts, and radiocarbon dating indicate that it was a single mass killing of more than 140 children and over 200 camelids directed by the Chimú state, c. AD 1450. Preliminary DNA analysis indicates that both boys and girls were chosen for sacrifice. Variability in forms of cranial modification (head shaping) and stable isotope analysis of carbon and nitrogen suggest that the children were a heterogeneous sample drawn from multiple regions and ethnic groups throughout the Chimú state. The Huanchaquito-Las Llamas mass sacrifice opens a new window on a previously unknown sacrificial ritual from fifteenth century northern coastal Peru. While the motivation for such a massive sacrifice is a subject for further research, there is archaeological evidence that it was associated with a climatic event (heavy rainfall and flooding) that could have impacted the economic, political and ideological stability of one of the most powerful states in the New World during the fifteenth century A.D.

Trepanation Procedures/Outcomes: Comparison of Prehistoric Peru with Other Ancient, Medieval, and American Civil War Cranial Surgery.

More prehistoric trepanned crania have been found in Peru than any other location worldwide. We examine trepanation practices and outcomes in Peru over nearly 2000 years from 400 BC to provide a perspective on the procedure with comparison with procedures/outcomes of other ancient, medieval, and American Civil War cranial surgery. Data on trepanation demographics, techniques, and survival rates were collected through the scientific analysis of more than 800 trepanned crania discovered in Peru, through field studies and the courtesy of museums and private collections in the United States and Peru, over nearly 3 decades. Data on procedures and outcomes of cranial surgery ancient, medieval, and during 19th-century through the American Civil war were obtained via a literature review. Successful trepanations from prehistoric times through the American Civil War likely involved shallow surgeries that did not pierce the dura mater. Although there are regional and temporal variations in ancient Peru, overall long-term survival rates for the study series were about 40% in the earliest period (400-200 BC), with improvement to a high of 91% in samples from AD 1000-1400, to an average of 75%-83% during the Inca Period (AD 1400s-1500). In comparison, the average cranial surgery mortality rate during the American Civil war was 46%-56%, and short- and long-term survival rates are unknown. The contrast in outcomes highlights the astonishing success of ancient cranial surgery in Peru in the treatment of living patients.

Reprint of-Differential diagnosis: Trepanation.

Trepanation is the scraping, cutting, or drilling of an opening (or openings) into the neurocranium. World surveys reveal that a number of ancient cultures experimented with cranial surgery, and that in some areas these practices continued into modern times. Archaeological discoveries of possible trepanations continue to be made, often from geographic areas or time periods from which the practice was not previously known. Unfortunately, most of these reports describe single crania with healed defects interpreted as trepanations. When evaluating a possible trepanation in a skull that lacks medical history or comes from an archaeological context where there is no other evidence that such operations were performed, a thorough differential diagnosis is essential. Identification of unhealed trepanations is a relatively straightforward exercise, since tool marks provide direct evidence of surgical intervention. A confident diagnosis is more difficult in healed defects of the skull, where the mechanism that produced an opening may be obscured by bone remodeling. There are many possible causes of defects of the skull vault, including congenital and developmental anomalies, trauma, infection, neoplasm, and taphonomic damage. For this reason, a careful differential diagnosis is essential for identifying surgical intervention and distinguishing it from cranial defects caused by other mechanisms.

Differential diagnosis: Trepanation.

Trepanation is the scraping, cutting, or drilling of an opening (or openings) into the neurocranium. World surveys reveal that a number of ancient cultures experimented with cranial surgery, and that in some areas these practices continued into modern times. Archaeological discoveries of possible trepanations continue to be made, often from geographic areas or time periods from which the practice was not previously known. Unfortunately, most of these reports describe single crania with healed defects interpreted as trepanations. When evaluating a possible trepanation in a skull that lacks medical history or comes from an archaeological context where there is no other evidence that such operations were performed, a thorough differential diagnosis is essential. Identification of unhealed trepanations is a relatively straightforward exercise, since tool marks provide direct evidence of surgical intervention. A confident diagnosis is more difficult in healed defects of the skull, where the mechanism that produced an opening may be obscured by bone remodeling. There are many possible causes of defects of the skull vault, including congenital and developmental anomalies, trauma, infection, neoplasm, and taphonomic damage. For this reason, a careful differential diagnosis is essential for identifying surgical intervention and distinguishing it from cranial defects caused by other mechanisms.

Craniofacial plasticity in ancient Peru.

Numerous studies have utilized craniometric data to explore the roles of genetic diversity and environment in human cranial shape variation. Peru is a particularly interesting region to examine cranial variation due to the wide variety of high and low altitude ecological zones, which in combination with rugged terrain have created isolated populations with vastly different physiological adaptations. This study examines seven samples from throughout Peru in an effort to understand the contributions of environmental adaptation and genetic relatedness to craniofacial variation at a regional scale. Morphological variation was investigated using a canonical discriminant analysis and Mahalanobis D(2) analysis. Results indicate that all groups are significantly different from one another with the closest relationship between Yauyos and Jahuay, two sites that are located geographically close in central Peru but in very different ecozones. The relationship between latitude/longitude and face shape was also examined with a spatial autocorrelation analysis (Moran's I) using ArcMap and show that there is significant spatial patterning for facial measures and geographic location suggesting that there is an association between biological variation and geographic location.

Violence and weapon-related trauma at Puruchuco-Huaquerones, Peru.

Conquest of indigenous peoples in North America is understood primarily through ethnohistorical documents, archaeological evidence, and osteological analyses. However, in the Central Andes, the colonial enterprise and its effects are understood only from postcontact historical and ethnohistorical sources. Few archaeological and bioarchaeological studies have investigated Spanish Conquest and colonialism in the Andean region [for exceptions see Klaus and Tam: Am J Phys Anthropol 138 (2009) 356-368; Wernke, in press; and Quilter, in press]. Here we describe bioarchaeological evidence of violence from the cemeteries of Huaquerones and 57AS03 within the archaeological zone of Puruchuco-Huaquerones, Peru (circa A.D. 1470-1540). A total of 258 individuals greater than 15 years of age were analyzed for evidence of traumatic injuries. Individuals were examined macroscopically and evidence of traumatic injuries was analyzed according to the skeletal element involved, the location of the injury on the skeletal element, and any additional complications of the injury. This study examines and compares the evidence of perimortem injuries on skeletonized individuals from the two cemeteries and focuses specifically on the interpretation of weapon-related perimortem injuries. Evidence of perimortem trauma is present in both cemeteries (18.6%, 48/258); however, the frequency of injuries in 57AS03 is greater than that in Huaquerones (25.0% vs. 13.0%). Several injuries from 57AS03 are consistent with documented cases of injuries from firearms and 16th Century European weapons. We believe that the nature and high frequency of perimortem trauma at 57AS03 provide evidence of the violence that occurred with Spanish Conquest of the Inca Empire.

Chapter 1: ancient trepanation.

Cranial trepanations began to be performed more than 5000 years ago in Europe and as early as the 5th century BC in the New World. It was only in the mid-19th century, however, that men of medicine began to realize that the openings in some of the unearthed ancient skulls were made by individuals skilled in surgery, and that the practice was routinely performed on the living. Some of the first reports on these unusual skulls and their significance came from pioneer neurologists and neurosurgeons, including Paul Broca and Victor Horsley. However, from the start, Broca and Horsley did not agree on why the operations were performed, and the logic behind these early cranial surgeries has continued to generate debate. In Peru, where more trepanned crania have been found than anywhere else, numerous skulls have been associated with head injuries from battles, a finding of special significance for neurologists, neurosurgeons, and neurohistorians.

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.

Biodistance analysis of the Moche sacrificial victims from Huaca de la Luna plaza 3C: Matrix method test of their origins.

The purpose of this study is to test two competing models regarding the origins of Early Intermediate Period (AD 200-750) sacrificial victims from the Huacas de Moche site using the matrix correlation method. The first model posits the sacrificial victims represent local elites who lost competitions in ritual battles with one another, while the other model suggests the victims were nonlocal warriors captured during warfare with nearby polities. We estimate biodistances for sacrificial victims from Huaca de la Luna Plaza 3C (AD 300-550) with eight previously reported samples from the north coast of Peru using both the mean measure of divergence (MMD) and Mahalanobis' distance (d2). Hypothetical matrices are developed based upon the assumptions of each of the two competing models regarding the origins of Moche sacrificial victims. When the MMD matrix is compared to the two hypothetical matrices using a partial-Mantel test (Smouse et al.: Syst Zool 35 (1986) 627-632), the ritual combat model (i.e. local origins) has a low and nonsignificant correlation (r = 0.134, P = 0.163), while the nonlocal origins model is highly correlated and significant (r = 0.688, P = 0.001). Comparisons of the d2 results and the two hypothetical matrices also produced low and nonsignificant correlation for the ritual combat model (r = 0.210, P = 0.212), while producing a higher and statistically significant result with the nonlocal origins model (r = 0.676, P = 0.002). We suggest that the Moche sacrificial victims represent nonlocal warriors captured in territorial combat with nearby competing polities.

Mummified trophy heads from Peru: diagnostic features and medicolegal significance.

Several forms of mummified human trophy heads were produced by prehistoric and historic native groups in South America. This paper describes the diagnostic features of trophy heads produced by the Nasca culture of ancient Peru. A growing interest in these mummified heads among collectors of Pre-Columbian art and antiquities has led to their illegal exportation from Peru, in violation of national and international antiquities laws. Requests from the Peruvian government to protect its cultural patrimony led the United States in 1997 to declare these heads as items subject to U.S. import restriction, along with six other categories of human remains. Despite such restrictions, Nasca trophy heads continue to reach private collectors outside of Peru and thus may be encountered by local, state, or federal law enforcement officials unfamiliar with their characteristic features and origin. The objective of this paper is to describe the features that allow Nasca trophy heads to be identified and distinguished from other archaeological and forensic specimens that may be submitted to a forensic anthropologist for identification.