DO WEAK OR STRONG ACIDS REMOVE CARBONATE CONTAMINATION FROM ANCIENT TOOTH ENAMEL MORE EFFECTIVELY? THE EFFECT OF ACID PRETREATMENT ON RADIOCARBON AND δ13C ANALYSES

ABSTRACT In hot environments, collagen, which is normally targeted when radiocarbon (14C) dating bone, rapidly degrades. With little other skeletal material suitable for 14C dating, it can be impossible to obtain dates directly on skeletal materials. A small amount of carbonate occurs in hydroxyapatite, the mineral phase of bone and tooth enamel, and has been used as an alternative to collagen. Unfortunately, the mineral phase is often heavily contaminated with exogenous carbonate causing 14C dates to underestimate the true age of a sample. Although tooth enamel, with its larger, more stable crystals and lower porosity, is likely to be more robust to diagenesis than bone, little work has been undertaken to investigate how exogenous carbonate can be effectively removed prior to 14C dating. Typically, acid is used to dissolve calcite and etch the surface of the enamel, but it is unclear which acid is most effective. This study repeats and extends earlier work using a wider range of samples and acids and chelating agents (hydrochloric, lactic, acetic and propionic acids, and EDTA). We find that weaker acids remove carbonate contaminants more effectively than stronger acids, and acetic acid is the most effective. However, accurate dates cannot always be obtained.

Historical Anatomical Collections of Human Remains: Exploring Their Reinterpretation as Representations of Racial Violence

We synthesize how the tools of molecular anthropology, integrated with analyses of skeletal material, can provide direct insights into the context-specific experiences of racial structural violence in the past. Our work—which is emblematic of how biological anthropologists are increasingly interested in exploring the embodied effects of structural and race-based violence—reveals how anthropology can illuminate past lived experiences that are otherwise invisible or inscrutable. This kind of integrative research is exposing the legacies of structural violence in producing anatomical collections and the embodied effects of structural violence evident within individuals in those collections.

A closer look at the forgotten bones of the Dolmen of Pedras Grandes (Odivelas, Portugal). (Examining old human remains 7).

The Dolmen of Pedras Grandes (Odivelas, Lisboa, Portugal) was discovered and excavated at the end of the 19th century by Carlos Ribeiro. In 2004, this monument was re-excavated by Rui Boaventura and a complete study was conducted. The Dolmen of Pedras Grandes presents a polygonal chamber and a very short passage and may have had a short period of burial activity in the 4thmillennium as indicated by the radiocarbon dates and the “archaic” artefacts. The relative and absolute dating enable us to assign this monument to the initial phase of megalithic funerary monumentality in south-central Portugal. Moreover, the recovery of human skeletal material offers an opportunity to obtain data on the biological profile and the health status of the human community who buried their dead in this megalithic tomb. In this paper are present new radiocarbon dates and isotopic analyses obtained from human bone samples from this tomb and also a complete anthropological study of the human skeletal material recovered in this monument. At least 13 individuals are represented in the skeletal assemblage, including 8 adults (> 16 years) and 5 non-adults, although this is certainly an underestimate due to the poor preservation of the bone assemblage. Young children, under the age of three years, are missing. A small number of pathologies were observed, including cranial trauma, degenerative joint disease and oral pathologies. The high frequency of stress indicators, more specifically linear enamel hypoplasia, is a notable feature of this assemblage. The new data are discussed in the context of the problem of the origin of megalithic monumentality in Central and Southern Portugal

Inca Human Sacrifices on Misti Volcano (Peru)

One of the most impressive examples of an Inca capacocha ceremony was discovered during an archaeological expedition to the summit of Misti volcano in 1998. The offerings at the site included several human sacrifices, along with fine ceramics and figurines made from gold, silver, and Spondylus sp. shell. One of the two burials appeared to contain the bones of males and the other of females. The sex was established based on the contents of the graves, because the fragile skeletal material had been badly affected by volcanic activity and exact identification was difficult to make in situ. To limit the risk of damage, the bones were excavated together with the surrounding soil and transported in frozen blocks to the Museo Santuarios Andinos of Universidad Católica de Santa María in Arequipa. This material was the object of a bioarchaeological investigation in February and March 2018. The results revealed that at least eight individuals had been buried in the graves. The findings have increased our understanding of the age categories and physical condition of the individuals chosen to be sacrificed during the capacocha ritual.

Did Akhenaten’s Founding of Akhetaten Cause a Malaria Epidemic?

This paper presents and discusses evidence for changes in the environment that would have taken place at the site of Amarna, ancient Akhetaten, during the rapid building and populating of the city in the reign of King Akhenaten. The evidence suggests that the effect of the founding of this city, with all the consequences of a changed environment on both sides of the river, could have been responsible for a malaria epidemic. This scenario is backed up by the high prevalence of signs of malaria in the skeletal material from Amarna, as well as in the short-lived history of the city, which was deserted after about fifteen years.

An ankylosaurian dinosaur from the Cenomanian Dunvegan Formation of northeastern British Columbia, Canada

Fragmentary but associated dinosaur bones collected in 1930 from the Pine River of northeastern British Columbia are identified here as originating from an ankylosaur. The specimen represents only the second occurrence of dinosaur skeletal material from the Cenomanian Dunvegan Formation and the first from Dunvegan outcrops in the province of British Columbia. Nodosaurid ankylosaur footprints are common ichnofossils in the formation, but the skeletal material described here is too fragmentary to confidently assign to either a nodosaurid or ankylosaurid ankylosaur. The Cenomanian is a time of major terrestrial faunal transitions in North America, but many localities of this age are located in the southern United States; the discovery of skeletal fossils from the Pine River demonstrates the potential for the Dunvegan Formation to produce terrestrial vertebrate fossils that may provide important new data on this significant transitional period during the Cretaceous.