Animal DNA in PCR reagents plagues ancient DNA research

Molecular archaeology brings the tools of molecular biology to bear on fundamental questions in archaeology, anthropology, evolution, and ecology. Ancient DNA research is becoming widespread as evolutionary biologists and archaeologists discover the power of the polymerase chain reaction (PCR) to amplify DNA from ancient plant and animal remains. However, the extraordinary susceptibility of PCR to contamination by extraneous DNA is not widely appreciated. We report the independent observation of DNA from domestic animals in PCR reagents and ancient samples in four separate laboratories. Since PCR conditions used in ancient DNA analyses are extremely sensitive, very low concentrations of contaminating DNA can cause false positives. Previously unidentified animal DNA in reagents can confound ancient DNA research on certain domestic animals, especially cows, pigs, and chickens.     

Teens and territory in contested spaces: Negotiating sectarian interfaces in Northern Ireland

The purpose of this article is to examine children's experiences of territory in one location in Northern Ireland. The research draws on stories, maps and focus group interviews with 80 children aged between 14–15 years of age, living in one of the most contested interface areas in Northern Ireland. Interface areas are locations where Catholics and Protestants live side by side in segregated communities divided by peace walls and other symbolic boundaries. Within these spaces, children made distinctions between place and territory. Place was referred to in relation to physical features of the surrounding landscape but more importantly as spaces where family and friendship ties were paramount. Territory on the other hand was referred to in terms of Protestant and Catholic identity.     

Rousseau's fulfillment of the natural public law tradition and his contribution to its demise

The recent research of Helena Rosenblatt, Hilail Gildin, Arthur Meltzer, and John Scott calls for a reconsideration of Rousseau's stance towards and effect on the natural public law tradition. This reconsideration is especially called for given the persuasive evidence and arguments that these scholars marshal to demonstrate the positive contribution of Rousseau to that tradition and to suggest that his pre-Kantian rational law teaching in the Social Contract is rooted in his post-Hobbesian stance towards natural law, especially in the Second Discourse. The work of these scholars builds upon others, especially on Leo Strauss, Victor Gourevitch, Jean Starobinski, Marc Plattner, Roger Masters and John Charvet, as well as Asher Horowitz, R. A. Leigh, Franz Haymann, and Robert Derathe, and completes the full range of alternative answers to our question. Their contributions are an invaluable scaffolding for fully grasping the issue and for proposing theses that could resolve it. Given the great debt owed to these scholars, the present inquiry begins with an overview and general assessment of their opinions on the issue, which is then followed by a close analysis of the relevant texts of Rousseau, especially the “Preface” to the Second Discourse.