Della Collins Cook

Pre-Columbian mycobacterial genomes reveal seals as a source of New World human tuberculosis

Modern strains of Mycobacterium tuberculosis from the Americas are closely related to those from Europe, supporting the assumption that human tuberculosis was introduced post-contact. This notion, however, is incompatible with archaeological evidence of pre-contact tuberculosis in the New World. Comparative genomics of modern isolates suggests that M. tuberculosis attained its worldwide distribution following human dispersals out of Africa during the Pleistocene epoch, although this has yet to be confirmed with ancient calibration points. Here we present three 1,000-year-old mycobacterial genomes from Peruvian human skeletons, revealing that a member of the M. tuberculosis complex caused human disease before contact. The ancient strains are distinct from known human-adapted forms and are most closely related to those adapted to seals and sea lions. Two independent dating approaches suggest a most recent common ancestor for the M. tuberculosis complex less than 6,000 years ago, which supports a Holocene dispersal of the disease. Our results implicate sea mammals as having played a role in transmitting the disease to humans across the ocean.

Skeletal evidence for child abuse: a physical anthropological perspective

Analysis of the skeletal remains of abused children can prove challenging for forensic pathologists and radiographers who are inexperienced in the direct examination of bones. In such cases, radiographically invisible skeletal lesions that document a history of trauma can often be identified by a physical anthropologist with appropriate osteological experience. This is illustrated by cases in which skeletal remains of four murdered children and a mentally handicapped adult produced evidence of antemortem trauma and perimortem injuries that was critical in developing murder cases against the assailants. In these cases, well-healed areas of subperiosteal new bone formation were identified that were below the threshold of radiographic detection. Such injuries provide strong evidence for a history of physical abuse.

Subsistence Base and Health in Prehistoric Illinois Valley: Evidence from the Human Skeleton

Abstract A variety of osteological techniques provide direct estimates of the effects of subsistence base changes on health in prehistoric populations. A model is presented for the interactions among demographic, skeletal and nutritional variables across the transition from hunting and gathering to maize agriculture based economies. Data on population composition, growth retardation, growth arrest markers, cortical bone dynamics, and nutrition‐related aspects of dental health are examined in the light of this model. These techniques permit a quantification of the biological impact of the transition from Woodland to Mississippian economies in the Lower Illinois Valley region from 0 to 1000 A. D.

Synchrotron Reveals Early Triassic Odd Couple: Injured Amphibian and Aestivating Therapsid Share Burrow

Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of vertebrate remains associated with these burrows leaves many ecological questions unanswered. Synchrotron scanning of a lithified burrow cast from the Early Triassic of the Karoo unveiled a unique mixed-species association: an injured temnospondyl amphibian (Broomistega) that sheltered in a burrow occupied by an aestivating therapsid (Thrinaxodon). The discovery of this rare rhinesuchid represents the first occurrence in the fossil record of a temnospondyl in a burrow. The amphibian skeleton shows signs of a crushing trauma with partially healed fractures on several consecutive ribs. The presence of a relatively large intruder in what is interpreted to be a Thrinaxodon burrow implies that the therapsid tolerated the amphibian’s presence. Among possible explanations for such unlikely cohabitation, Thrinaxodon aestivation is most plausible, an interpretation supported by the numerous Thrinaxodon specimens fossilised in curled-up postures. Recent advances in synchrotron imaging have enabled visualization of the contents of burrow casts, thus providing a novel tool to elucidate not only anatomy but also ecology and biology of ancient tetrapods.

Isotopic Evidence for Diet at Chau Hiix, Belize: Testing Regional Models of Hierarchy and Heterarchy

The stable carbon and nitrogen isotope values (o13C, §15N) of collagen and the carbon isotope value of structural carbonate in bioapatite were measured in the bones and teeth of Early Classic to Historic period Maya buried at Chau Hiix, Belize. Diet at Chau Hiix comprised a mixture of resources but contained an unusual amount of protein from high trophic levels. There were no differences between the diets of males and females, and there were no consistent changes in diet from birth to age 12. However, children consumed more maize than adults during all time periods. Similarities in general diet and temporal changes at Chau Hiix, Lamanai, and Altun Ha suggest their participation in a regional socioeconomic system. The diets of the highest-status Early Classic individuals at Chau Hiix, Lamanai, and Altun Ha were different from one another and from those of other individuals buried at their respective sites. We suggest that elites created or attempted to create hierarchies of food consumption within sites during the Classic period and that a heterarchy existed among elites from different sites. During the Postclassic period the major protein component of the Chau Hiix diet shifted from terrestrial animal and/or freshwater resources to reef resources, which suggests increased associations with coastal sites. Temporal changes in diet at Chau Hiix closely paralleled changes at Lamanai, but diets at the two sites were distinct during all time periods.

Tuberculosis in the New World: a study of ribs from the Schild Mississippian population, West-Central Illinois

Vertebral lesions have been the main evidence for infection by the Mycobacterium tuberculosis complex (MTC) in paleopathology. Skeletal involvement is expected in a small percentage of infected individuals. Recently, several authors report a correlation between rib lesions and tuberculosis (TB) complex infection. This study tests the hypothesis that rib lesions can serve as a useful marker for MTC infection within the Mississippian Schild skeletal collection from West-Central Illinois. Ribs from 221 adults and juveniles were examined, and affected individuals were tested for TB complex infection. DNA from rib samples of affected individuals was amplified with primers targeting the IS6110 insertion element, which is common to all members of the TB complex. Although it cannot allow discrimination between different species of TB, IS6110 is present in many copies within their genomes, and its presence is thus an indication of MTC infection. The results support the use of rib lesions as a marker for TB infection. Additionally, we demonstrate that MTC DNA can be recovered from ribs that lack lesions in individuals who have lesions of other bones. We recommend that an examination of ribs be incorporated into investigations for TB.

Natural Selection and Morphological Variability: The Case of Europe From Neolithic to Modern Times [and Comments and Reply]

Two hypotheses concerning the influence of natural selection intensity on intra- and interpopulational variability of metric characteristics of the human skull ar tested. Using data on 58 series from Europe and its environs dating from Neolithic to modern times, it has been found that with the decline of the decline of the intensity of operation of natural selection (1) intragroup variability increases, (2) intergroup variability decreases, and (3) there is a trend toward shorter, wider, and lower braincase and shorter upper face.

5 – THERMALLY INDUCED CHANGES IN THE STABLE CARBON AND NITROGEN ISOTOPE RATIOS OF CHARRED BONES

Publisher Summary Cremations, whether accidental or deliberate, are difficult to work with because they are usually fragmentary. However, cremation is rarely complete, and cremated burials often provide bone fragments suitable for many types of osteological investigations. Morphological analyses of cremated bones can provide information about sex, age, health, and cause of death. It is often assumed that cremation produces highly oxidized bone fragments that are little more than inorganic ash, but this is not the case for most prehistoric cremations. Bone fragments often display a gradient of thermal alteration, ranging from calcined through blackened to apparently unaltered, sometimes even on the same bone. Burned bones can also be subjected to chemical studies, although these are rarely done. Many cremations produce bones that still contain organic matter in the form of thermally altered organics or reduced carbon. This is especially true for prehistoric cremations, where the large amount of fuel necessary for a total cremation may not have been readily available to nonindustrial societies. In many cases, charred bones from archaeological contexts can be expected to contain more organic carbon than uncharred bones from the same context, because reduced carbon in charred bone is more resistant to diagenetic change than uncharred collagen and other organic fractions of bone. Cremated burials would provide an abundant and promising source of paleodietary data through isotope studies if correct techniques were available.

Koniag Eskimo Tooth Ablation: Was Hrdlicka Right After All?

by DELLA COLLINS COOK Department of Anthropology, Indiana University, Bloomington, Ind. 47405, U.S.A. 31 x 80 In 1940, Ales Hrdlicka published a paper in which he argued that the intentional removal of one or more of the permanent teeth was a custom among palearctic peoples. He described examples from Siberia, North America, and South America, finding in this distribution support for the Siberian origin of American Indians. The age-specific frequencies of missing teeth suggested to him something of the nature of the cultural content of the practice: As specimens of this nature accumulated, itbecame evident hat we were confronted here with a definite custom, which in all probabilitv was a part of the initiation rites of the youth, parallel to that in aboriginal Australia nd other parts of the world, and which conferred on the sufferers a certain distinction. [p. 1] The strong probability is that in general, or at least in the majority of the cases, the ablations both in Siberia and America were of a ritual nature. It would be difficult toattribute any material proportion of them to either disease or to accident; and the evidence, especially the variety of the removals, speaks against any large proportion of the losses of the teeth reported being due to branding or to punishment. [p. 30] The meaning of the ritual ablation could only have been sacrificial, with secondarily a test of endurance. The practice falls into the same class with circumcision a d could have had no connection, it would seem, with decorative, cosmetic, or simple torture mutilations. [p. 30] The ablations, curiously, though differing considerably infrequency in different groups, were never universal. In most of the tribes or localities they were in fact rather are, affecting but a few percent of the individuals. There evidently was some selection-based perhaps on clan or other form of social organization. [p. 31]

Ancient DNA from the Schild site in Illinois: Implications for the Mississippian transition in the Lower Illinois River Valley

Archaeologists have long debated whether rapid cultural change in the archaeological record is due to in situ developments, migration of a new group into the region, or the spread of new cultural practices into an area through existing social networks, with the local peoples adopting and adapting practices from elsewhere as they see fit (acculturation). Researchers have suggested each of these explanations for the major cultural transition that occurred at the beginning of the Mississippian period (AD 1050) across eastern North America. In this study, we used ancient DNA to test competing hypotheses of migration and acculturation for the culture change that occurred between the Late Woodland (AD 400-1050) and Mississippian (AD 1050-1500) periods in the Lower Illinois River Valley. We obtained sequences of the first hypervariable segment of the mitochondrial genome (mtDNA) from 39 individuals (17 Late Woodland, 22 Mississippian) interred in the Schild cemetery in western Illinois, and compared these lineages to ancient mtDNA lineages present at other sites in the region. Computer simulations were used to test a null hypothesis of population continuity from Late Woodland to Mississippian times at the Schild site and to investigate the possibility of gene flow from elsewhere in the region. Our results suggest that the Late Woodland to Mississippian cultural transition at Schild was not due to an influx of people from elsewhere. Instead, it is more likely that the transition to Mississippian cultural practices at this site was due to a process of acculturation.