Roman roads to prosperity: Persistence and non-persistence of public infrastructure
Carl-Johan Dalgaard et al.
Journal of Comparative Economics, forthcoming
In this paper, we explore the link between public transport infrastructure investments made during antiquity and the presence of infrastructure today; as well as the link between early infrastructure and economic activity, both in the past and in the present. We examine the territory under dominion of the Roman Empire at the zenith of its geographical extension (117 CE), and find a remarkable pattern of persistence showing that greater Roman road density goes along with (a) greater modern road density, (b) greater settlement formation in 500 CE, and (c) greater economic activity in 2010–2020. Exploiting a natural experiment, we find that persistence in road density and the strong link between early road density and contemporary economic development weaken to the point of insignificance in areas where the use of wheeled vehicles was abandoned and caravan trade routes replaced road-based trade from the first millennium CE until the late modern period. Studying channels of persistence, we identify the emergence of market towns during the early medieval period and the modern era as a robust mechanism sustaining the persistent effects of the Roman roads network. Our results contribute to a deeper understanding of the channels through which persistence in comparative development comes about.
Millet, Rice, and Isolation: Origins and Persistence of the World's Most Enduring Mega-State
James Kai-sing Kung et al.
Southern Methodist University Working Paper, June 2022
We propose and test empirically a theory describing the endogenous formation and persistence of mega-states, using China as an example. We suggest that the relative timing of the emergence of agricultural societies, and their distance from each other, set off a race between their autochthonous state-building projects, which determines their extent and persistence. Using a novel dataset describing the historical presence of Chinese states, prehistoric development, the diffusion of agriculture, and migratory distance across 1° × 1° grid cells in eastern Asia, we find that cells that adopted agriculture earlier and were close to Erlitou -- the earliest political center in eastern Asia -- remained under Chinese control for longer and continue to be a part of China today. By contrast, cells that adopted agriculture early and were located further from Erlitou developed into independent states, as agriculture provided the fertile ground for state-formation, while isolation provided time for them to develop and confront the expanding Chinese empire. Our study sheds important light on why eastern Asia kept reproducing a mega-state in the area that became China and on the determinants of its borders with other states.
The Prehistoric Origins of European Economic Integration
Social Philosophy and Policy, Winter 2021, Pages 261-306
It appears likely that at its peak the classical economy was almost as large as that of Western Europe during the Industrial Revolution. The following review of the archeological and document evidence indicates that three events occurring in the first half of the first millennium BC trigger the emergence of a specialized and integrated classical economy after 500 BC: (i) growth in demand for silver as a medium of exchange in economies in the Near East; (ii) technical breakthroughs in hull construction and sailing rig in merchant shipping of the late Bronze Age; (iii) perfection of ferrous metallurgy into the European hinterland. This last event raised agricultural productivity to a level capable of supporting the occupational specialization needed to sustain a vigorous trading economy. To these initial causes may be added the diffusion of alphabetic writing. While it did not create opportunities for long-distance trade, the diffusion of writing supplied the means of responding on a scale large enough economically to matter.
Why Warmth Matters More Than Competence: A New Evolutionary Approach
Adar Eisenbruch & Max Krasnow
Perspectives on Psychological Science, forthcoming
Multiple lines of evidence suggest that there are two major dimensions of social perception, often called warmth and competence, and that warmth is prioritized over competence in multiple types of social decision-making. Existing explanations for this prioritization argue that warmth is more consequential for an observer’s welfare than is competence. We present a new explanation for the prioritization of warmth based on humans’ evolutionary history of cooperative partner choice. We argue that the prioritization of warmth evolved because ancestral humans faced greater variance in the warmth of potential cooperative partners than in their competence but greater variance in competence over time within cooperative relationships. These each made warmth more predictive than competence of the future benefits of a relationship, but because of differences in the distributions of these traits, not because of differences in their intrinsic consequentiality. A broad, synthetic review of the anthropological literature suggests that these conditions were characteristic of the ecologies in which human social cognition evolved, and agent-based models demonstrate the plausibility of these selection pressures. We conclude with future directions for the study of preferences and the further integration of social and evolutionary psychology.
Hidden signatures of early fire at Evron Quarry (1.0 to 0.8 Mya)
Zane Stepka et al.
Proceedings of the National Academy of Sciences, 21 June 2022
Pyrotechnology is a key element of hominin evolution. The identification of fire in early hominin sites relies primarily on an initial visual assessment of artifacts’ physical alterations, resulting in potential underestimation of the prevalence of fire in the archaeological record. Here, we used a suite of spectroscopic techniques to counter the absence of visual signatures for fire and demonstrate the presence of burnt fauna and lithics at the Lower Paleolithic (LP) open-air site of Evron Quarry (Israel), dated between 1.0 and 0.8 Mya and roughly contemporaneous to Gesher Benot Ya’aqov where early pyrotechnology has been documented. We propose reexamining finds from other LP sites lacking visual clues of pyrotechnology to yield a renewed perspective on the origin, evolution, and spatiotemporal dispersal of the relationship between early hominin behavior and fire use.
Grey wolf genomic history reveals a dual ancestry of dogs
Anders Bergström et al.
The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000–30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.
Cosmogenic nuclide dating of Australopithecus at Sterkfontein, South Africa
Darryl Granger et al.
Proceedings of the National Academy of Sciences, 5 July 2022
Sterkfontein is the most prolific single source of Australopithecus fossils, the vast majority of which were recovered from Member 4, a cave breccia now exposed by erosion and weathering at the landscape surface. A few other Australopithecus fossils, including the StW 573 skeleton, come from subterranean deposits [T. C. Partridge et al., Science 300, 607–612 (2003); R. J. Clarke, K. Kuman, J. Hum. Evol. 134, 102634 (2019)]. Here, we report a cosmogenic nuclide isochron burial date of 3.41 ± 0.11 million years (My) within the lower middle part of Member 4, and simple burial dates of 3.49 ± 0.19 My in the upper middle part of Member 4 and 3.61 ± 0.09 My in Jacovec Cavern. Together with a previously published isochron burial date of 3.67 ± 0.16 My for StW 573 [D. E. Granger et al., Nature 522, 85–88 (2015)], these results place nearly the entire Australopithecus assemblage at Sterkfontein in the mid-Pliocene, contemporaneous with Australopithecus afarensis in East Africa. Our ages for the fossil-bearing breccia in Member 4 are considerably older than the previous ages of ca. 2.1 to 2.6 My interpreted from flowstones associated with the same deposit. We show that these previously dated flowstones are stratigraphically intrusive within Member 4 and that they therefore underestimate the true age of the fossils.
Emergence and intensification of dairying in the Caucasus and Eurasian steppes
Ashley Scott et al.
Nature Ecology & Evolution, June 2022, Pages 813–822
Archaeological and archaeogenetic evidence points to the Pontic–Caspian steppe zone between the Caucasus and the Black Sea as the crucible from which the earliest steppe pastoralist societies arose and spread, ultimately influencing populations from Europe to Inner Asia. However, little is known about their economic foundations and the factors that may have contributed to their extensive mobility. Here, we investigate dietary proteins within the dental calculus proteomes of 45 individuals spanning the Neolithic to Greco-Roman periods in the Pontic–Caspian Steppe and neighbouring South Caucasus, Oka–Volga–Don and East Urals regions. We find that sheep dairying accompanies the earliest forms of Eneolithic pastoralism in the North Caucasus. During the fourth millennium BC, Maykop and early Yamnaya populations also focused dairying exclusively on sheep while reserving cattle for traction and other purposes. We observe a breakdown in livestock specialization and an economic diversification of dairy herds coinciding with aridification during the subsequent late Yamnaya and North Caucasus Culture phases, followed by severe climate deterioration during the Catacomb and Lola periods. The need for additional pastures to support these herds may have driven the heightened mobility of the Middle and Late Bronze Age periods. Following a hiatus of more than 500 years, the North Caucasian steppe was repopulated by Early Iron Age societies with a broad mobile dairy economy, including a new focus on horse milking.
Reconstructing the history of founder events using genome-wide patterns of allele sharing across individuals
Rémi Tournebize, Gillian Chu & Priya Moorjani
PLoS Genetics, June 2022
Founder events play a critical role in shaping genetic diversity, fitness and disease risk in a population. Yet our understanding of the prevalence and distribution of founder events in humans and other species remains incomplete, as most existing methods require large sample sizes or phased genomes. Thus, we developed ASCEND that measures the correlation in allele sharing between pairs of individuals across the genome to infer the age and strength of founder events. We show that ASCEND can reliably estimate the parameters of founder events under a range of demographic scenarios. We then apply ASCEND to two species with contrasting evolutionary histories: ~460 worldwide human populations and ~40 modern dog breeds. In humans, we find that over half of the analyzed populations have evidence for recent founder events, associated with geographic isolation, modes of sustenance, or cultural practices such as endogamy. Notably, island populations have lower population sizes than continental groups and most hunter-gatherer, nomadic and indigenous groups have evidence of recent founder events. Many present-day groups – including Native Americans, Oceanians and South Asians – have experienced more extreme founder events than Ashkenazi Jews who have high rates of recessive diseases due their known history of founder events. Using ancient genomes, we show that the strength of founder events differs markedly across geographic regions and time – with three major founder events related to the peopling of Americas and a trend in decreasing strength of founder events in Europe following the Neolithic transition and steppe migrations. In dogs, we estimate extreme founder events in most breeds that occurred in the last 25 generations, concordant with the establishment of many dog breeds during the Victorian times. Our analysis highlights a widespread history of founder events in humans and dogs and elucidates some of the demographic and cultural practices related to these events.
Ancient DNA reveals five streams of migration into Micronesia and matrilocality in early Pacific seafarers
Yue-Chen Liu et al.
Science, 1 July 2022, Pages 72-79
Micronesia began to be peopled earlier than other parts of Remote Oceania, but the origins of its inhabitants remain unclear. We generated genome-wide data from 164 ancient and 112 modern individuals. Analysis reveals five migratory streams into Micronesia. Three are East Asian related, one is Polynesian, and a fifth is a Papuan source related to mainland New Guineans that is different from the New Britain–related Papuan source for southwest Pacific populations but is similarly derived from male migrants ~2500 to 2000 years ago. People of the Mariana Archipelago may derive all of their precolonial ancestry from East Asian sources, making them the only Remote Oceanians without Papuan ancestry. Female-inherited mitochondrial DNA was highly differentiated across early Remote Oceanian communities but homogeneous within, implying matrilocal practices whereby women almost never raised their children in communities different from the ones in which they grew up.