Old Data
The origins of political institutions and property rights
Giacomo Benati, Carmine Guerriero & Federico Zaina
Journal of Comparative Economics, forthcoming
Abstract:
We study the possible cooperation between nonelites exerting an unobservable effort and elites unable to commit to direct transfers and, thus, always assure the nonelites’ participation. The elites can, however, incentivize investment by granting to the nonelites strong property rights to the input and a more inclusive political process, which entrusts them with control over fiscal policies. Adverse production conditions force the elites to enact strong nonelites’ political and property rights to convince them that a sufficient part of the returns on joint investments will be shared via public good provision. These reforms assure cooperation. When, instead, the expected investment return is large, the elites keep control over fiscal policies but refrain from weakening the nonelites’ property rights, while strengthening their own, if the production conditions are sufficiently opaque. Then, the expected cost of providing the extra public good guaranteeing the nonelites’ participation is too large. These predictions are consistent with novel data on 44 major Mesopotamian polities observed for each half-century from 3050 to 1750 BCE. While a lower growing season temperature favored a larger division of the decision-making power and stronger farmers’ use rights to land, only the latter are related to the diffusion of the very opaque viticulture. In addition, only the inclusiveness of the political process fostered the provision of public and ritual buildings as well as conscripted armies. Crucially, our results are robust to considering the trade potential, the severity of conflicts, and the degree of urbanization.
Human Occupation of the North American Colorado Plateau ∼37,000 Years Ago
Timothy Rowe et al.
Frontiers in Ecology and Evolution, July 2022
Abstract:
Calibrating human population dispersals across Earth’s surface is fundamental to assessing rates and timing of anthropogenic impacts and distinguishing ecological phenomena influenced by humans from those that were not. Here, we describe the Hartley mammoth locality, which dates to 38,900-36,250 cal BP by AMS 14C analysis of hydroxyproline from bone collagen. We accept the standard view that elaborate stone technology of the Eurasian Upper Paleolithic was introduced into the Americas by arrival of the Native American clade ∼16,000 cal BP. It follows that if older cultural sites exist in the Americas, they might only be diagnosed using nuanced taphonomic approaches. We employed computed tomography (CT and μCT) and other state-of-the-art methods that had not previously been applied to investigating ancient American sites. This revealed multiple lines of taphonomic evidence suggesting that two mammoths were butchered using expedient lithic and bone technology, along with evidence diagnostic of controlled (domestic) fire. That this may be an ancient cultural site is corroborated by independent genetic evidence of two founding populations for humans in the Americas, which has already raised the possibility of a dispersal into the Americas by people of East Asian ancestry that preceded the Native American clade by millennia. The Hartley mammoth locality thus provides a new deep point of chronologic reference for occupation of the Americas and the attainment by humans of a near-global distribution.
Evolutionary loss of complexity in human vocal anatomy as an adaptation for speech
Takeshi Nishimura et al.
Science, 12 August 2022, Pages 760-763
Abstract:
Human speech production obeys the same acoustic principles as vocal production in other animals but has distinctive features: A stable vocal source is filtered by rapidly changing formant frequencies. To understand speech evolution, we examined a wide range of primates, combining observations of phonation with mathematical modeling. We found that source stability relies upon simplifications in laryngeal anatomy, specifically the loss of air sacs and vocal membranes. We conclude that the evolutionary loss of vocal membranes allows human speech to mostly avoid the spontaneous nonlinear phenomena and acoustic chaos common in other primate vocalizations. This loss allows our larynx to produce stable, harmonic-rich phonation, ideally highlighting formant changes that convey most phonetic information. Paradoxically, the increased complexity of human spoken language thus followed simplification of our laryngeal anatomy.
Endocranial ontogeny and evolution in early Homo sapiens: The evidence from Herto, Ethiopia
Christoph Zollikofer et al.
Proceedings of the National Academy of Sciences, 9 August 2022
Abstract:
Fossils and artifacts from Herto, Ethiopia, include the most complete child and adult crania of early Homo sapiens. The endocranial cavities of the Herto individuals show that by 160,000 y ago, brain size, inferred from endocranial size, was similar to that seen in modern human populations. However, endocranial shape differed from ours. This gave rise to the hypothesis that the brain itself evolved substantially during the past ∼200,000 y, possibly in tandem with the transition from Middle to Upper Paleolithic techno-cultures. However, it remains unclear whether evolutionary changes in endocranial shape mostly reflect changes in brain morphology rather than changes related to interaction with maxillofacial morphology. To discriminate between these effects, we make use of the ontogenetic fact that brain growth nearly ceases by the time the first permanent molars fully erupt, but the face and cranial base continue to grow until adulthood. Here we use morphometric data derived from digitally restored immature and adult H. sapiens fossils from Herto, Qafzeh, and Skhul (HQS) to track endocranial development in early H. sapiens. Until the completion of brain growth, endocasts of HQS children were similar in shape to those of modern human children. The similarly shaped endocasts of fossil and modern children indicate that our brains did not evolve substantially over the past 200,000 y. Differences between the endocranial shapes of modern and fossil H. sapiens adults developed only with continuing facial and basicranial growth, possibly reflecting substantial differences in masticatory and/or respiratory function.
Long-distance trade in the Middle Chalcolithic of the southern Levant: The case of the olivine beads from Tel Tsaf, Jordan Valley, Israel
Danny Rosenberg et al.
PLoS ONE, August 2022
Abstract:
Eight olivine beads found at the Middle Chalcolithic site of Tel Tsaf (ca. 5,200-4,700 cal. BC), Jordan Valley, Israel, underscore a new facet of interregional exchange for this period. The current paper presents the olivine beads assemblage, its morphometric and technological characteristics, and chemical composition. The results of the chemical analysis suggest that all eight beads derive from the same source. By means of comparison with the chemical characteristics of known olivine sources, we argue for a northeastern African-western Arabian provenience and cautiously suggest Ethiopia as a probable origin. Finally, we discuss the significance of the assemblage, its possible origin, and the mechanisms that may have brought the beads to the site.