4 research outputs found
Miniaturization optimized weapon killing power during the social stress of late pre-contact North America (AD 600-1600)
Before Europeans arrived to Eastern North America, prehistoric, indigenous peoples experienced a number of changes that culminated in the development of sedentary, maize agricultural lifeways of varying complexity. Inherent to these lifeways were several triggers of social stress including population nucleation and increase, intergroup conflict (warfare), and increased territoriality. Here, we examine whether this period of social stress co-varied with deadlier weaponry, specifically, the design of the most commonly found prehistoric archery component in late pre-contact North America: triangular stone arrow tips (TSAT). The examination of modern metal or carbon projectiles, arrows, and arrowheads has demonstrated that smaller arrow tips penetrate deeper into a target than do larger ones. We first experimentally confirm that this relationship applies to arrow tips made from stone hafted onto shafts made from wood. We then statistically assess a large sample (n = 742) of late pre-contact TSAT and show that these specimens are extraordinarily small. Thus, by miniaturizing their arrow tips, prehistoric people in Eastern North America optimized their projectile weaponry for maximum penetration and killing power in warfare and hunting. Finally, we verify that these functional advantages were selected across environmental and cultural boundaries. Thus, while we cannot and should not rule out stochastic, production economizing, or non-adaptive cultural processes as an explanation for TSAT, overall our results are consistent with the hypothesis that broad, socially stressful demographic changes in late pre-contact Eastern North America resulted in the miniaturizationâand augmented lethalityâof stone tools across the region
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Miniaturization optimized weapon killing power during the social stress of late pre-contact North America (AD 600-1600).
Before Europeans arrived to Eastern North America, prehistoric, indigenous peoples experienced a number of changes that culminated in the development of sedentary, maize agricultural lifeways of varying complexity. Inherent to these lifeways were several triggers of social stress including population nucleation and increase, intergroup conflict (warfare), and increased territoriality. Here, we examine whether this period of social stress co-varied with deadlier weaponry, specifically, the design of the most commonly found prehistoric archery component in late pre-contact North America: triangular stone arrow tips (TSAT). The examination of modern metal or carbon projectiles, arrows, and arrowheads has demonstrated that smaller arrow tips penetrate deeper into a target than do larger ones. We first experimentally confirm that this relationship applies to arrow tips made from stone hafted onto shafts made from wood. We then statistically assess a large sample (n = 742) of late pre-contact TSAT and show that these specimens are extraordinarily small. Thus, by miniaturizing their arrow tips, prehistoric people in Eastern North America optimized their projectile weaponry for maximum penetration and killing power in warfare and hunting. Finally, we verify that these functional advantages were selected across environmental and cultural boundaries. Thus, while we cannot and should not rule out stochastic, production economizing, or non-adaptive cultural processes as an explanation for TSAT, overall our results are consistent with the hypothesis that broad, socially stressful demographic changes in late pre-contact Eastern North America resulted in the miniaturization-and augmented lethality-of stone tools across the region
Pregnancy and neonatal outcomes of COVID -19: coreporting of common outcomes from PAN-COVID and AAP-SONPM registries
Objective
Few large cohort studies have reported data on maternal, fetal, perinatal and neonatal outcomes associated with severe acute respiratory syndrome coronavirus 2 (SARSâCoVâ2) infection in pregnancy. We report the outcome of infected pregnancies from a collaboration formed early during the pandemic between the investigators of two registries, the UK and Global Pregnancy and Neonatal outcomes in COVIDâ19 (PANâCOVID) study and the American Academy of Pediatrics (AAP) Section on NeonatalâPerinatal Medicine (SONPM) National Perinatal COVIDâ19 Registry.
Methods
This was an analysis of data from the PANâCOVID registry (1 January to 25 July 2020), which includes pregnancies with suspected or confirmed maternal SARSâCoVâ2 infection at any stage in pregnancy, and the AAPâSONPM National Perinatal COVIDâ19 registry (4 April to 8 August 2020), which includes pregnancies with positive maternal testing for SARSâCoVâ2 from 14âdays before delivery to 3âdays after delivery. The registries collected data on maternal, fetal, perinatal and neonatal outcomes. The PANâCOVID results are presented overall for pregnancies with suspected or confirmed SARSâCoVâ2 infection and separately in those with confirmed infection.
Results
We report on 4005 pregnant women with suspected or confirmed SARSâCoVâ2 infection (1606 from PANâCOVID and 2399 from AAPâSONPM). For obstetric outcomes, in PANâCOVID overall and in those with confirmed infection in PANâCOVID and AAPâSONPM, respectively, maternal death occurred in 0.5%, 0.5% and 0.2% of cases, early neonatal death in 0.2%, 0.3% and 0.3% of cases and stillbirth in 0.5%, 0.6% and 0.4% of cases. Delivery was preterm (<â37âweeks' gestation) in 12.0% of all women in PANâCOVID, in 16.1% of those women with confirmed infection in PANâCOVID and in 15.7% of women in AAPâSONPM. Extreme preterm delivery (<â27âweeks' gestation) occurred in 0.5% of cases in PANâCOVID and 0.3% in AAPâSONPM. Neonatal SARSâCoVâ2 infection was reported in 0.9% of all deliveries in PANâCOVID overall, in 2.0% in those with confirmed infection in PANâCOVID and in 1.8% in AAPâSONPM; the proportions of neonates tested were 9.5%, 20.7% and 87.2%, respectively. The rates of a smallâforâgestationalâage (SGA) neonate were 8.2% in PANâCOVID overall, 9.7% in those with confirmed infection and 9.6% in AAPâSONPM. Mean gestationalâageâadjusted birthâweight Zâscores were â0.03 in PANâCOVID and â0.18 in AAPâSONPM.
Conclusions
The findings from the UK and USA registries of pregnancies with SARSâCoVâ2 infection were remarkably concordant. Preterm delivery affected a higher proportion of women than expected based on historical and contemporaneous national data. The proportions of pregnancies affected by stillbirth, a SGA infant or early neonatal death were comparable to those in historical and contemporaneous UK and USA data. Although maternal death was uncommon, the rate was higher than expected based on UK and USA population data, which is likely explained by underascertainment of women affected by milder or asymptomatic infection in pregnancy in the PANâCOVID study, although not in the AAPâSONPM study. The data presented support strong guidance for enhanced precautions to prevent SARSâCoVâ2 infection in pregnancy, particularly in the context of increased risks of preterm delivery and maternal mortality, and for priority vaccination of pregnant women and women planning pregnancy. Copyright Š 2021 ISUOG. Published by John Wiley & Sons Ltd