High levels of consanguinity in a child from Paquimé, Chihuahua, Mexico.

This study reports results from the ancient DNA analysis of a unique child burial at Paquimé, northern Chihuahua, Mexico. Located between Mesoamerican and Ancestral Puebloan groups, Paquimé (also known as Casas Grandes) was a vibrant multicultural centre during the 13th-14th centuries AD. Archaeologists have long debated Paquimé's social organization.

Genetic continuity and change among the Indigenous peoples of California.

Before the colonial period, California harboured more language variation than all of Europe, and linguistic and archaeological analyses have led to many hypotheses to explain this diversity. We report genome-wide data from 79 ancient individuals from California and 40 ancient individuals from Northern Mexico dating to 7,400-200 years before present (BP). Our analyses document long-term genetic continuity between people living on the Northern Channel Islands of California and the adjacent Santa Barbara mainland coast from 7,400 years BP to modern Chumash groups represented by individuals who lived around 200 years BP.

Ethical considerations when co-analyzing ancient DNA and data from private genetic databases.

Ancient DNA studies have begun to explore the possibility of identifying identical DNA segments shared between historical and living people. This research requires access to large genetic datasets to maximize the likelihood of identifying previously unknown, close genetic connections. Direct-to-consumer genetic testing companies, such as 23andMe, Inc.

The genetic legacy of African Americans from Catoctin Furnace.

Few African Americans have been able to trace family lineages back to ancestors who died before the 1870 United States Census, the first in which all Black people were listed by name. We analyzed 27 individuals from Maryland's Catoctin Furnace African American Cemetery (1774-1850), identifying 41,799 genetic relatives among consenting research participants in 23andMe, Inc.'s genetic database.

Ethics of DNA research on human remains: five globally applicable guidelines.

We are a group of archaeologists, anthropologists, curators and geneticists representing diverse global communities and 31 countries. All of us met in a virtual workshop dedicated to ethics in ancient DNA research held in November 2020. There was widespread agreement that globally applicable ethical guidelines are needed, but that recent recommendations grounded in discussion about research on human remains from North America are not always generalizable worldwide.

COMBINING ANCIENT DNA AND RADIOCARBON DATING DATA TO INCREASE CHRONOLOGICAL ACCURACY.

This paper examines how ancient DNA data can enhance radiocarbon dating. Because there is a limit to the number of years that can separate the dates of death of related individuals, the ability to identify relatives through ancient DNA analysis can serve as a constraint on radiocarbon date range estimates. To determine the number of years that can separate related individuals, we modeled maximums derived from biological extremes of human reproduction and death ages and compiled data from historic and genealogical death records.

A genetic history of the pre-contact Caribbean.

Humans settled the Caribbean about 6,000 years ago, and ceramic use and intensified agriculture mark a shift from the Archaic to the Ceramic Age at around 2,500 years ago. Here we report genome-wide data from 174 ancient individuals from The Bahamas, Haiti and the Dominican Republic (collectively, Hispaniola), Puerto Rico, Curaçao and Venezuela, which we co-analysed with 89 previously published ancient individuals. Stone-tool-using Caribbean people, who first entered the Caribbean during the Archaic Age, derive from a deeply divergent population that is closest to Central and northern South American individuals; contrary to previous work, we find no support for ancestry contributed by a population related to North American individuals.

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.

Reconstructing the Deep Population History of Central and South America.

We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America.