Eurasian back-migration into Northeast Africa was a complex and multifaceted process.

Recent studies have identified Northeast Africa as an important area for human movements during the Holocene. Eurasian populations have moved back into Northeastern Africa and contributed to the genetic composition of its people. By gathering the largest reference dataset to date of Northeast, North, and East African as well as Middle Eastern populations, we give new depth to our knowledge of Northeast African demographic history. By employing local ancestry methods, we isolated the Non-African parts of modern-day Northeast African genomes and identified the best putative source populations. Egyptians and Sudanese Copts bore most similarities to Levantine populations whilst other populations in the region generally had predominantly genetic contributions from the Arabian peninsula rather than Levantine populations for their Non-African genetic component. We also date admixture events and investigated which factors influenced the date of admixture and find that major linguistic families were associated with the date of Eurasian admixture. Taken as a whole we detect complex patterns of admixture and diverse origins of Eurasian admixture in Northeast African populations of today.

Distinguishing African bovids using Zooarchaeology by Mass Spectrometry (ZooMS): New peptide markers and insights into Iron Age economies in Zambia.

Assessing past foodways, subsistence strategies, and environments depends on the accurate identification of animals in the archaeological record. The high rates of fragmentation and often poor preservation of animal bones at many archaeological sites across sub-Saharan Africa have rendered archaeofaunal specimens unidentifiable beyond broad categories, such as "large mammal" or "medium bovid". Identification of archaeofaunal specimens through Zooarchaeology by Mass Spectrometry (ZooMS), or peptide mass fingerprinting of bone collagen, offers an avenue for identification of morphologically ambiguous or unidentifiable bone fragments from such assemblages. However, application of ZooMS analysis has been hindered by a lack of complete reference peptide markers for African taxa, particularly bovids. Here we present the complete set of confirmed ZooMS peptide markers for members of all African bovid tribes. We also identify two novel peptide markers that can be used to further distinguish between bovid groups. We demonstrate that nearly all African bovid subfamilies are distinguishable using ZooMS methods, and some differences exist between tribes or sub-tribes, as is the case for Bovina (cattle) vs. Bubalina (African buffalo) within the subfamily Bovinae. We use ZooMS analysis to identify specimens from extremely fragmented faunal assemblages from six Late Holocene archaeological sites in Zambia. ZooMS-based identifications reveal greater taxonomic richness than analyses based solely on morphology, and these new identifications illuminate Iron Age subsistence economies c. 2200-500 cal BP. While the Iron Age in Zambia is associated with the transition from hunting and foraging to the development of farming and herding, our results demonstrate the continued reliance on wild bovids among Iron Age communities in central and southwestern Zambia Iron Age and herding focused primarily on cattle. We also outline further potential applications of ZooMS in African archaeology.

Ancient proteins provide evidence of dairy consumption in eastern Africa.

Consuming the milk of other species is a unique adaptation of Homo sapiens, with implications for health, birth spacing and evolution. Key questions nonetheless remain regarding the origins of dairying and its relationship to the genetically-determined ability to drink milk into adulthood through lactase persistence (LP). As a major centre of LP diversity, Africa is of significant interest to the evolution of dairying. Here we report proteomic evidence for milk consumption in ancient Africa. Using liquid chromatography tandem mass spectrometry (LC-MS/MS) we identify dairy proteins in human dental calculus from northeastern Africa, directly demonstrating milk consumption at least six millennia ago. Our findings indicate that pastoralist groups were drinking milk as soon as herding spread into eastern Africa, at a time when the genetic adaptation for milk digestion was absent or rare. Our study links LP status in specific ancient individuals with direct evidence for their consumption of dairy products.

A monumental cemetery built by eastern Africa's first herders near Lake Turkana, Kenya.

Monumental architecture is a prime indicator of social complexity, because it requires many people to build a conspicuous structure commemorating shared beliefs. Examining monumentality in different environmental and economic settings can reveal diverse reasons for people to form larger social units and express unity through architectural display. In multiple areas of Africa, monumentality developed as mobile herders created large cemeteries and practiced other forms of commemoration. The motives for such behavior in sparsely populated, unpredictable landscapes may differ from well-studied cases of monumentality in predictable environments with sedentary populations. Here we report excavations and ground-penetrating radar surveys at the earliest and most massive monumental site in eastern Africa. Lothagam North Pillar Site was a communal cemetery near Lake Turkana (northwest Kenya) constructed 5,000 years ago by eastern Africa's earliest pastoralists. Inside a platform ringed by boulders, a 119.5-m2 mortuary cavity accommodated an estimated minimum of 580 individuals. People of diverse ages and both sexes were buried, and ornaments accompanied most individuals. There is no evidence for social stratification. The uncertainties of living on a "moving frontier" of early herding-exacerbated by dramatic environmental shifts-may have spurred people to strengthen social networks that could provide information and assistance. Lothagam North Pillar Site would have served as both an arena for interaction and a tangible reminder of shared identity.