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Concept: Inca


The Inca Empire is claimed to have driven massive population movements in western South America, and to have spread Quechua, the most widely-spoken language family of the indigenous Americas. A test-case is the Chachapoyas region of northern Peru, reported as a focal point of Inca population displacements. Chachapoyas also spans the environmental, cultural and demographic divides between Amazonia and the Andes, and stands along the lowest-altitude corridor from the rainforest to the Pacific coast. Following a sampling strategy informed by linguistic data, we collected 119 samples, analysed for full mtDNA genomes and Y-chromosome STRs. We report a high indigenous component, which stands apart from the network of intense genetic exchange in the core central zone of Andean civilization, and is also distinct from neighbouring populations. This unique genetic profile challenges the routine assumption of large-scale population relocations by the Incas. Furthermore, speakers of Chachapoyas Quechua are found to share no particular genetic similarity or gene-flow with Quechua speakers elsewhere, suggesting that here the language spread primarily by cultural diffusion, not migration. Our results demonstrate how population genetics, when fully guided by the archaeological, historical and linguistic records, can inform multiple disciplines within anthropology.

Concepts: South America, Bolivia, Andes, Ecuador, Peru, Inca Empire, Quechua, Inca


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 to 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 U.S. 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. While 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.

Concepts: Time, United States, Al-Andalus, American Civil War, Civil war, Inca Empire, Inca, Franklin Pierce


Santiago-Rodriguez et al. [1] report on the putative gut microbiome and resistome of Inca and Italian mummies, and find that Italian mummies exhibit higher bacterial diversity compared to the Inca mummies.[…].

Concepts: DNA, Evolution, Ancient Egypt, Inca Empire, Inca


Paleoparasitological studies have demonstrated that changes in environment or culture are reflected in the patterns of parasitic infection diseases in populations worldwide. The advent of agriculture and animal domestication, with its accompanying reduction in human mobility and expanding population involves changes in or emergence of, parasites, the so-called first epidemiological transition. Cultural processes related to territory occupation contribute to both loss and acquisition of parasites. The archaeological site Lluta 57 in the Lluta Valley, Chile, provides a chronology of the transition from the pre-Inca or Late Intermediate Period (LIP), through the Late or Inca Period (LP), to the Hispanic Contact Period (HCP), providing the possibility of evaluating this epidemiological transition. The aim of this study was to conduct a paleoparasitological investigation of to gain insight into the dynamics of parasitism in Lluta people throughout the Inca expansion. Fourteen human coprolites from the three periods were rehydrated, submitted to spontaneous sedimentation, and examined by light microscopy for the presence of intestinal parasite eggs, pollen grains, and micro-remains. Eggs of four parasites: Enterobius vermicularis, Trichostrongylus sp., Trichuris sp., and Eimeria macusaniensis were recovered. Frequency, diversity, and number of parasite eggs per sample increased over the studied time period. Trichostrongylus sp. and E. macusaniensis were recorded in the region for the first time. Enterobius vermicularis eggs, absent in the LIP, were present as a hyper-infection in LP. The presence of E. macusaniensis is likely related to exploitation of llamas, which were used for food and transport and as sacrificial offerings. The paleobotanical analysis revealed ten families of pollen grains, as well as phytoliths and floral remains. In contrast to parasitological results, a diachronic pattern was not detected. Evolution of the settlements, with the advent of larger, more densely populated, villages, could have influenced the emergence and intensification of transmission of parasites in the region. The study showed that the Inca expansion influenced host-parasite-environment relationships in the Lluta Valley.

Concepts: Parasites, Population, Intestinal parasite, Parasitism, Population density, Inca Empire, Pinworm, Inca


The El Plomo mummy was a pre-Columbian Incan child who was found mummified in the Andes Mountains above an altitude of 17,700 feet. In the environment, natural mummification occurred due to low temperatures and strong winds. Dating measurements (relative dating) by experts from the National Museum of Natural History of Chile established that the mummified body corresponds the Inca period (1,450 to 1,500 AD). In 2003, the body was transferred to the University of Chile Medical School for exhaustive medical examination. Tissue samples from the right quadriceps muscle were extracted and fixed in glutaraldehyde and postfixed in osmium tetroxide to obtain ultrathin sections to be observed by transmission electron microscope. Images were recorded on photographic paper, digitalized and analyzed by experts on morphology. Results showed a preservation of cell boundaries in striated muscle cells, but specific subcellular organelles or contractile sarcomeric units (actin and myosin) were unable to be recognized. However, the classical ultrastructural morphology of the polypeptide collagen type I was preserved intact both in primary and secondary organization. Therefore, we concluded that the process of natural mummification by freezing and strong winds is capable of damaging the ultrastructure of muscle cells and preserving collagen type I intact.

Concepts: Muscle, Myosin, Chile, Andes, Inca Empire, Santiago, Chile, Mummy, Inca


Researchers, using checklists, have identified that 30%-90% of patients make errors in inhaler use. It is not certain whether these errors affect the delivery of medication. We have developed an electronic monitor (INCA™) that records audio each time an inhaler is used, providing objective information on inhaler technique. The aim of this study was to assess the effect that correctly identified inhaler errors, with the INCA device, have on drug delivery.

Concepts: Dosage forms, The Delivery, Inca


Taking as a base our retrospective study of 2760 cases of cutaneous lymphoproliferations from the LYMPHOPATH and GFELC networks, we analyzed the doubtful and discordant cases between non-expert and expert pathologists, and the interest of clinicopathological confrontation.

Concepts: Inca Empire, Inca