Native
Dairying, diseases and the evolution of lactase persistence in Europe
Richard Evershed et al.
Nature, forthcoming
Abstract:
In European and many African, Middle Eastern and southern Asian populations, lactase persistence (LP) is the most strongly selected monogenic trait to have evolved over the past 10,000 years. Although the selection of LP and the consumption of prehistoric milk must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions. Here we provide detailed distributions of milk exploitation across Europe over the past 9,000 years using around 7,000 pottery fat residues from more than 550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Notably, LP selection varying with levels of prehistoric milk exploitation is no better at explaining LP allele frequency trajectories than uniform selection since the Neolithic period. In the UK Biobank cohort of 500,000 contemporary Europeans, LP genotype was only weakly associated with milk consumption and did not show consistent associations with improved fitness or health indicators. This suggests that other reasons for the beneficial effects of LP should be considered for its rapid frequency increase. We propose that lactase non-persistent individuals consumed milk when it became available but, under conditions of famine and/or increased pathogen exposure, this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitation — proxies for these drivers — provide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.
Ancestral Livelihoods and Moral Universalism: Evidence from Transhumant Pastoralist Societies
Etienne Le Rossignol & Sara Lowes
NBER Working Paper, July 2022
Abstract:
Moral universalism, the extent to which individuals exhibit similar altruism and trust towards in-group and out-group members, varies widely across societies. We test the hypothesis from anthropology that the requirements of transhumant pastoralism – a livelihood in which populations seasonally migrate and herd livestock – made individuals highly interdependent and cohesive within groups but hostile to individuals beyond the radius of extended kin. Using global data, we find that historical reliance on transhumant pastoralism is strongly predictive of greater in-group relative to out-group trust. This result is consistent across countries, between residents of the same country, among second-generation migrants, and with an instrumental variable strategy. We find evidence that these results are specific to transhumant pastoralism. The effects are particularly pronounced when transhumant pastoralists interact with groups that rely on other forms of economic production and in areas that are prone to climate shocks and conflict. Finally, we explore the economic implications of limited moral universalism. We find that greater reliance on transhumant pastoralism is associated with less objective promotion criteria within firms and smaller firm size.
Drought-Induced Civil Conflict Among the Ancient Maya
Douglas Kennett et al.
Nature Communications, July 2022
Abstract:
The influence of climate change on civil conflict and societal instability in the premodern world is a subject of much debate, in part because of the limited temporal or disciplinary scope of case studies. We present a transdisciplinary case study that combines archeological, historical, and paleoclimate datasets to explore the dynamic, shifting relationships among climate change, civil conflict, and political collapse at Mayapan, the largest Postclassic Maya capital of the Yucatán Peninsula in the thirteenth and fourteenth centuries CE. Multiple data sources indicate that civil conflict increased significantly and generalized linear modeling correlates strife in the city with drought conditions between 1400 and 1450 cal. CE. We argue that prolonged drought escalated rival factional tensions, but subsequent adaptations reveal regional-scale resiliency, ensuring that Maya political and economic structures endured until European contact in the early sixteenth century CE.
The Spanish Mission Legacy on Native American Reservations
Lee Alston, Marie Christine Duggan & Julio Alberto Ramos Pastrana
NBER Working Paper, July 2022
Abstract:
We explore the long run impact of the Spanish missions on Native American outcomes in the early 20th century. Native communities who interacted with Spanish missionaries developed into enclaves which blended Catholicism with native culture. Some survived assaults on their property rights by Mexico and the US to persist as reservations into the 20th century. We found that having extensive contact with missions increased the percentage of Native Americans Catholic, decreased crime rates, and increased income from agriculture and overall earnings from wages. Surprisingly, we found no impact on education.
Tufas indicate prolonged periods of water availability linked to human occupation in the southern Kalahari
Jessica von der Meden et al.
PLoS ONE, July 2022
Abstract:
Detailed, well-dated palaeoclimate and archaeological records are critical for understanding the impact of environmental change on human evolution. Ga-Mohana Hill, in the southern Kalahari, South Africa, preserves a Pleistocene archaeological sequence. Relict tufas at the site are evidence of past flowing streams, waterfalls, and shallow pools. Here, we use laser ablation screening to target material suitable for uranium-thorium dating. We obtained 33 ages covering the last 110 thousand years (ka) and identify five tufa formation episodes at 114–100 ka, 73–48 ka, 44–32 ka, 15–6 ka, and ~3 ka. Three tufa episodes are coincident with the archaeological units at Ga-Mohana Hill dating to ~105 ka, ~31 ka, and ~15 ka. Based on our data and the coincidence of dated layers from other local records, we argue that in the southern Kalahari, from ~240 ka to ~71 ka wet phases and human occupation are coupled, but by ~20 ka during the Last Glacial Maximum (LGM), they are decoupled.