Ethics and applications of isotope analysis in archaeology.

This synthesis explores specific ethical questions that commonly arise in isotopic analysis. For more than four decades, isotope analysis has been employed in archeological studies to explore past human and animal dietary habits, mobility patterns, and the environment in which a human or animal inhabited during life. These analyses require consideration of ethical issues. While theoretical concepts are discussed, we focus on practical aspects: working with descendant communities and other rights holders, choosing methods, creating and sharing data, and working mindfully within academia. These layers of respect and care should surround our science. This paper is relevant for specialists in isotope analysis as well as those incorporating these methods into larger projects. By covering the whole of the research process, from design to output management, we appeal broadly to archaeology and provide actionable solutions that build on the discussions in the general field.

Community partnerships are fundamental to ethical ancient DNA research.

The ethics of the scientific study of Ancestors has long been debated by archaeologists, bioanthropologists, and, more recently, ancient DNA (aDNA) researchers. This article responds to the article "Ethics of DNA research on human remains: five globally applicable guidelines" published in 2021 in Nature by a large group of aDNA researchers and collaborators. We argue that these guidelines do not sufficiently consider the interests of community stakeholders, including descendant communities and communities with potential, but yet unestablished, ties to Ancestors. We focus on three main areas of concern with the guidelines. First is the false separation of "scientific" and "community" concerns and the consistent privileging of researcher perspectives over those of community members. Second, the commitment of the guidelines' authors to open data ignores the principles and practice of Indigenous Data Sovereignty. Further, the authors argue that involving community members in decisions about publication and data sharing is unethical. We argue that excluding community perspectives on "ethical" grounds is convenient for researchers, but it is not, in fact, ethical. Third, we stress the risks of not consulting communities that have established or potential ties to Ancestors, using two recent examples from the literature. Ancient DNA researchers cannot focus on the lowest common denominator of research practice, the bare minimum that is legally necessary. Instead, they should be leading multidisciplinary efforts to create processes to ensure communities from all regions of the globe are identified and engaged in research that affects them. This will often present challenges, but we see these challenges as part of the research, rather than a distraction from the scientific endeavor. If a research team does not have the capacity to meaningfully engage communities, questions must be asked about the value and benefit of their research.

Ancient DNA from the skeletons of Roopkund Lake reveals Mediterranean migrants in India.

Situated at over 5,000 meters above sea level in the Himalayan Mountains, Roopkund Lake is home to the scattered skeletal remains of several hundred individuals of unknown origin. We report genome-wide ancient DNA for 38 skeletons from Roopkund Lake, and find that they cluster into three distinct groups. A group of 23 individuals have ancestry that falls within the range of variation of present-day South Asians. A further 14 have ancestry typical of the eastern Mediterranean. We also identify one individual with Southeast Asian-related ancestry. Radiocarbon dating indicates that these remains were not deposited simultaneously. Instead, all of the individuals with South Asian-related ancestry date to ~800 CE (but with evidence of being deposited in more than one event), while all other individuals date to ~1800 CE. These differences are also reflected in stable isotope measurements, which reveal a distinct dietary profile for the two main groups.

Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis.

Stable carbon and oxygen isotope analysis of human and animal tooth enamel carbonate has been applied in paleodietary, paleoecological, and paleoenvironmental research from recent historical periods back to over 10 million years ago. Bulk approaches provide a representative sample for the period of enamel mineralization, while sequential samples within a tooth can track dietary and environmental changes during this period. While these methodologies have been widely applied and described in archaeology, ecology, and paleontology, there have been no explicit guidelines to aid in the selection of necessary lab equipment and to thoroughly describe detailed laboratory sampling and protocols. In this article, we document textually and visually, the entire process from sampling through pretreatment and diagenetic screening to make the methodology more widely available to researchers considering its application in a variety of laboratory settings.