Ancient Microbial DNA in Dental Calculus: A New method for Studying Rapid Human Migration Events

Ancient human migrations provide the critical genetic background to historical and contemporary human demographic patterns. However, our ability to infer past human migration events, especially those that occurred over rapid timescales, is often limited. A key example is the peopling of Polynesia, where the timing is relatively well defined, but the exact routes taken during the final stages and the source populations are not. Here, we discuss the technical limitations of current methods for inferring rapid human migration events, using the final stages of Polynesian migration as an example. We also introduce a promising new proxy method to infer human migrations—patterns of bacterial evolution within ancient dental calculus (calcified plaque). While we focus on Polynesia, this method should be applicable to other past migrations, enhancing our understanding of human prehistory and revealing the crucial events that shaped it.     

Radiocarbon Chronometry of Site QJ-280, Quebrada Jaguay,a Terminal Pleistocene to Early Holocene Fishing Site in Southern Peru

Excavations in 1970, 1996, and 1999 at Site QJ-280, Quebrada Jaguay, in southern Peru, yielded enough dateable terrestrial plant material to establish an extensive radiocarbon chronology for the site. QJ-280 is one of oldest well-dated fishing sites in the Americas: it was occupied from the terminal Pleistocene to the mid-Holocene (about 13,000–8,300 calibrated years BP) based on 42 terrestrial radiocarbon dates, encompassing the Jaguay and Machas Phases of the local archaeological sequence. In addition to the terrestrial dates, radiocarbon measurements on valves of two marine surf clam (Mesodesma donacium) individuals from a single, well-dated mid-Holocene Manos Phase archaeological context have provided insight into marine upwelling conditions during the occupation of Quebrada Jaguay. The marine reservoir age varied between 130 and 730 ¹⁴C years during the brief lives of the two clams (up to 5 years each), and varied by up to 530 ¹⁴C years within an individual valve, suggesting strong and variable deep marine upwelling; conditions broadly similar to those that exist in coastal Peru today. These rapid variations in marine radiocarbon age suggest that marine radiocarbon dates from environments with variable upwelling could be skewed by up to hundreds of years.     

Method and Memory in the Midwestern "Lincoln Inquiry": Oral Testimony and Abraham Lincoln Studies, 1865 1938

This article narrates the role of oral testimony in the fieldof Abraham Lincoln studies from 1865 through the 1930s. Collectedin the form of letters, affidavits, and face-to-face interviews,this mounting body of "eyewitness evidence" dominated the discoursefor two generations and reflective, public practice culminatedin the organization of a "Lincoln Inquiry" in the Midwest duringthe 1920s and 1930s. For a time, practitioners successfullydefended themselves against increasing positivist assaults onthe credibility of oral testimony. Their interests and effortsresonate with later oral history practice and theory about method,authorship, performance, and memory, and their story highlightsthe contingency inherent in the development of oral historicalpractice in America.     

Stable Isotope Analysis of Human and Animal Remains at the Qijiaping Site in Middle Gansu,China

Intercontinental exchanges between communities living in different parts of Eurasia during the late prehistoric period have become increasingly popular as a topic of archaeological research. The Qijia culture, found in northwest China, is one of the key archaeological cultures that can shed light on trans‐Eurasian exchange because a variety of imports are found in this cultural context. These imports include new cereals and animals, which suggest that human diets may also have changed compared with previous periods. To understand human and animal diets of the Qijia culture, carbon and nitrogen isotope ratios from human and animal skeletal remains were analysed from the type site of the Qijia culture at Qijiaping. The results demonstrate that human diet at the site mainly consisted of millet and animals fed on millet. C₃ cereals, such as wheat and barley, did not contribute significantly to human diet, and no isotopic differences were found between adult and subadult diets. Furthermore, three outlying human results raise the possibility of exogenous individuals, perhaps in relation to the parallel movement of animals, crops and goods. This study provides human and animal dietary information for evaluating the nature of exchange and diffusion in eastern Eurasia at this time. Copyright © 2013 John Wiley & Sons, Ltd.     

Applying forensic techniques to interpret cranial fracture patterns in an archaeological specimen

This paper presents some of the basic principles of bone fracture physics and outlines characteristics used by forensic anthropologists to distinguish gunshot trauma from blunt trauma. The fracture pattern of a cranium from a historic cemetery in Memphis, Tennessee provides an example of how the mechanism of trauma could be misinterpreted. The pattern of the perimortem fractures is indicative of gunshot trauma with a bullet entering one side of the vault and impacting the opposite side. Identification of radiating fractures, concentric heaving fractures, and observation of the direction of bevel on the fractured surfaces are essential for interpretation of the mechanism that produced the injury.     

Colgi, Cajal and the Neuron Doctrine

Camillo Golgi and Santiago Ramon y Cajal shared the Nobel Prize in 1906 for their work on the histology of the nerve cell, but both held diametrically opposed views about the Neuron Doctrine which emphasizes the structural, functional and developmental singularity of the nerve cell. Golgi's reticularist views remained entrenched and his work on the nervous system did not venture greatly into new territories after its original flowering, which had greater impact than is now commonly credited. Cajal, by contrast, by the time he was awarded the Nobel Prize, was already breaking new ground with a new staining technique in the field of peripheral nerve regeneration, seeing the reconstruction of a severed nerve by sprouting from the proximal stump as another manifestation of the Neuron Doctrine. Paradoxically, identical studies were going on simultaneously in Golgi's laboratory in the hands of Aldo Perroncito, but the findings did not seem to influence Golgi's thinking on the Neuron Doctrine.