Kevin Lewis

November 27, 2021

Earliest evidence for human use of tobacco in the Pleistocene Americas
Daron Duke et al.
Nature Human Behaviour, forthcoming

Current archaeological research on cultigens emphasizes the protracted and intimate human interactions with wild species that defined paths to domestication and, with certain plants, profoundly impacted humanity. Tobacco arguably has had more impact on global patterns in history than any other psychoactive substance, but how deep its cultural ties extend has been widely debated. Excavations at the Wishbone site, directed at the hearth-side activities of the early inhabitants of North America’s desert west, have uncovered evidence for human tobacco use approximately 12,300 years ago, 9,000 years earlier than previously documented. Here we detail the preservation context of the site, discuss its cultural affiliation and suggest ways that the tobacco may have been used. The find has implications for our understanding of deep-time human use of intoxicants and its sociocultural intersection with food crop domestication. 

Relationship between rice farming and polygenic scores potentially linked to agriculture in China
Chen Zhu et al.
Royal Society Open Science, August 2021

Following domestication in the lower Yangtze River valley 9400 years ago, rice farming spread throughout China and changed lifestyle patterns among Neolithic populations. Here, we report evidence that the advent of rice domestication and cultivation may have shaped humans not only culturally but also genetically. Leveraging recent findings from molecular genetics, we construct a number of polygenic scores (PGSs) of behavioural traits and examine their associations with rice cultivation based on a sample of 4101 individuals recently collected from mainland China. A total of nine polygenic traits and genotypes are investigated in this study, including PGSs of height, body mass index, depression, time discounting, reproduction, educational attainment, risk preference, ADH1B rs1229984 and ALDH2 rs671. Two-stage least-squares estimates of the county-level percentage of cultivated land devoted to paddy rice on the PGS of age at first birth (b = −0.029, p = 0.021) and ALDH2 rs671 (b = 0.182, p < 0.001) are both statistically significant and robust to a wide range of potential confounds and alternative explanations. These findings imply that rice farming may influence human evolution in relatively recent human history. 

Volcanic climate forcing, extreme cold and the Neolithic Transition in the northern US Southwest
R.J. Sinensky et al.
Antiquity, forthcoming

The impacts on global climate of the AD 536 and 541 volcanic eruptions are well attested in palaeoclimatic datasets and in Eurasian historical records. Their effects on farmers in the arid uplands of western North America, however, remain poorly understood. The authors investigate whether extreme cold caused by these eruptions influenced the scale, scope and timing of the Neolithic Transition in the northern US Southwest. Archaeological tree-ring and radiocarbon dates, along with settlement survey data suggest that extreme cooling generated the physical and social space that enabled early farmers to transition from kin-focused socio-economic strategies to increasingly complex and widely shared forms of social organisation that served as foundational elements of burgeoning Ancestral Pueblo societies. 

Harmful algal blooms and cyanotoxins in Lake Amatitlán, Guatemala, coincided with ancient Maya occupation in the watershed
Matthew Neal Waters et al.
Proceedings of the National Academy of Sciences, 30 November 2021

Human-induced deforestation and soil erosion were environmental stressors for the ancient Maya of Mesoamerica. Furthermore, intense, periodic droughts during the Terminal Classic Period, ca. Common Era 830 to 950, have been documented from lake sediment cores and speleothems. Today, lakes worldwide that are surrounded by dense human settlement and intense riparian land use often develop algae/cyanobacteria blooms that can compromise water quality by depleting oxygen and producing toxins. Such environmental impacts have rarely been explored in the context of ancient Maya settlement. We measured nutrients, biomarkers for cyanobacteria, and the cyanotoxin microcystin in a sediment core from Lake Amatitlán, highland Guatemala, which spans the last ∼2,100 y. The lake is currently hypereutrophic and characterized by high cyanotoxin concentrations from persistent blooms of the cyanobacterium Microcystis aeruginosa. Our paleolimnological data show that harmful cyanobacteria blooms and cyanotoxin production occurred during periods of ancient Maya occupation. Highest prehistoric concentrations of cyanotoxins in the sediment coincided with alterations of the water system in the Maya city of Kaminaljuyú, and changes in nutrient stoichiometry and maximum cyanobacteria abundance were coeval with times of greatest ancient human populations in the watershed. These prehistoric episodes of cyanobacteria proliferation and cyanotoxin production rivaled modern conditions in the lake, with respect to both bloom magnitude and toxicity. This suggests that pre-Columbian Maya occupation of the Lake Amatitlán watershed negatively impacted water potability. Prehistoric cultural eutrophication indicates that human-driven nutrient enrichment of water bodies is not an exclusively modern phenomenon and may well have been a stressor for the ancient Maya. 

Stunting is the natural condition of human height
Christiane Scheffler & Michael Hermanussen
American Journal of Human Biology, forthcoming

Sample and Method:
We revisited height from archeological data (10 000–1000 BC), and historical growth studies (1877–1913). We analyzed height, weight, and skinfold thickness of 1666 Indonesian schoolchildren from six representative rural and urban elementary schools in Bali and West Timor with a stunting prevalence of up to 50%.

Stature in the Holocene prehistory of the Near East and Europe varied with maxima for women usually ranging below 160 cm, and maxima for men between 165 and 170 cm. Stature never rose above 170 cm. European and white US-American schoolchildren of the 19th and 20th century were generally short with average height ranging between −1.5 and −2.2 hSDS, yet in the absence of any evidence of chronic or recurrent undernutrition or frequent illness, poverty, or disadvantageous living conditions. The same is found in contemporary Indonesian schoolchildren. 

Climate-driven early agricultural origins and development in the Nile Delta, Egypt
Xiaoshuang Zhao et al.
Journal of Archaeological Science, forthcoming

Long-standing arguments regarding the early cultural transition, the domestication of plants and the impacts of climate change on past Egyptian societies remain contentious. In this paper, we demonstrate that grazing started at our study site, Kom El-Khilgan in the NE Nile Delta, ca. 7000 years ago, which was several hundred years prior to crop farming. We examined pollen-spores and non-pollen palynomorphs (NPP) in a 1-m-deep sediment profile (KH-1) in the study site, defined archaeologically as the Pre-Dynastic (>5.9 ka) in age. Our results show that before ca. 7.0 ka, major floods prevailed in the Nile Delta, as highly-concentrated Podocarpus and Polypodiaceae were transported from the East African highlands and Cyperaceae of higher Nile flow indication. This humid phase was succeeded by a brief period of drying climate ca. 7.0–6.6 ka, allowing the entry of the first settlers who commenced grazing their animals on previously inundated wetlands. This change is indicated by the remarkable increase in fungal spores (Cercophora, Sordaria, Coniochaeta cf. Ligniaria) from accumulations of animal dung. At ca. 6.6 ka, the abrupt appearance of domesticated cereal pollen (Poaceae >35 μm) and cereal grass pathogens (Pericornia and Sorosporium) suggests an amelioration of the climate that allowed the introduction of cereal crops and related water management activities. Grazing and cropping co-existed for the remainder of the record during the time when there occurred a mega-tendency of climate drying towards recent time. A drought event recognized ca. 4.2 ka led to the collapse of the Old Kingdom. 

Genomic transformation and social organization during the Copper Age–Bronze Age transition in southern Iberia
Vanessa Villalba-Mouco et al.
Science Advances, November 2021

The emerging Bronze Age (BA) of southeastern Iberia saw marked social changes. Late Copper Age (CA) settlements were abandoned in favor of hilltop sites, and collective graves were largely replaced by single or double burials with often distinctive grave goods indirectly reflecting a hierarchical social organization, as exemplified by the BA El Argar group. We explored this transition from a genomic viewpoint by tripling the amount of data available for this period. Concomitant with the rise of El Argar starting ~2200 cal BCE, we observe a complete turnover of Y-chromosome lineages along with the arrival of steppe-related ancestry. This pattern is consistent with a founder effect in male lineages, supported by our finding that males shared more relatives at sites than females. However, simple two-source models do not find support in some El Argar groups, suggesting additional genetic contributions from the Mediterranean that could predate the BA.

Briquetage and Brine: Living and Working at the Classic Maya Salt Works of Ek Way Nal, Belize
Heather McKillop & Cory Sills
Ancient Mesoamerica, forthcoming

Systematic flotation survey and spatial analysis of artifacts at the submerged salt work of Ek Way Nal reveal evidence of a residence, salt kitchens, and additional activities. Ek Way Nal is one of 110 salt works associated with a Late to Terminal Classic (A.D. 600–900) salt industry known as the Paynes Creek Salt Works. Wooden posts that form the walls of 10 buildings are remarkably preserved in a peat bog below the sea floor providing an opportunity to examine surface artifacts in relation to buildings. Numerous salt kitchens have been located at the Paynes Creek Salt Works by evidence of abundant briquetage — pottery associated with boiling brine over fires to make salt. As one of the largest salt works with 10 buildings, there is an opportunity to examine variability in building use. Systematic flotation survey over the site and flagging and mapping individual artifacts and posts provide evidence that the Ek Way Nal salt makers had a residence near the salt kitchens, along with evidence of salting fish for subsistence or surplus household production. The results are compared with ethnographic evidence from Sacapulas and other salt works.


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