An Assessment of Stone Weapon Tip Standardization During the Clovis-Folsom Transition in the Western United States

It has long been assumed that Folsom points are more standardized than Clovis points, although an adequate test of this proposition has yet to be undertaken. Here, we address that deficiency by using data from a sample of Folsom and Clovis points recovered from sites across the western United States. We used geometric morphometric techniques to capture point shape and then conducted statistical analyses of variability associated with Clovis and Folsom point bases and blades. Our results demonstrate that Folsom bases and blades are less variable than those on earlier Clovis points, indicating an increase in point standardization during the Early Paleoindian period. In addition, despite published claims to the contrary, Clovis and Folsom point bases are no more variable than blades. Based on these results, we conducted additional analyses to examine the modularity and size of Clovis and Folsom points. The results suggest Clovis points have more integrated base and blade segments than Folsom points. We suggest that several classes of Clovis points - intended for different functions - might have been in use during the Clovis period and that the later Folsom points might have served only as weapon tips, the shape of which were constrained by the fluting process

Determination of the cold storage conditions of some apple cultivars

Bu araştırma 2000 2002 yıllan arasında Eğirdir Bahçe Kültürleri Araştırma Enstitüsü ve Süleyman Demirel Üniversitesi Ziraat Fakültesi Bahçe Bitkileri Bölümü Derim Sonrası Fizyoloji Laboratuvarında yürütülmüştür. Çalışmada M9 anacı üzerine aşılı Granny Smith, Imparatore ve Idared elma çeşitlerinin soğukta depolanma koşulları incelenmiştir. Uygun depolama koşulunu belirlemek için iki farklı zamanda derilen elmalar ilk yıl 0 oC ve % 90-95 nispi nem , ikinci yıl -1, 0 ve +2 oC sıcaklık ve yine % 90-95 nispi nem koşullarına sahip üç farklı soğuk odada 6 ay süreyle depolanmışlardır. Depolama boyunca birer ay aralıklarla depodan çıkartılan örneklerde ağırlık kaybı, meyve eti sertliği, suda çözünebilir kuru madde, titre edilebilir asitlik ve renk değerleriyle beraber fizyolojik ve patojen kaynaklı bozulmalar incelenmiştir. Deneme sonuçlarına göre Eğirdir ekolojisinde M9 anacı üzerinde yetiştirilen Granny Smith, Imparatore ve Idared elma çeşitlerinin 0 oC sıcaklık ve % 90-95 nispi nem koşullarında 5-6 ay depolanabileceği saptanmıştır.This research was carried out at Horticulture Research Institute of Egirdir and Postharvest Physiology Lab. of Department of Horticulture, Faculty of Agriculture, University of Süleyman Demirel between 2000 and 20002. Storage conditions of apple varieties Granny Smith, Imparatore and Idared grafted on M9 rootstock were investigated. In order to determine the optimum storage condition, these varieties harvested two different stage were stored at 0 Ctemperature and 90-95%relative humidity in the first year, and at -1, 0 and +2 Cand 90-95% RHin the second year for 6 months. During the storage period, weight loss, fruit flesh firmness, total solible solid, titretable acidity, colorimeter values (L*, a*, b*) and physiological disorders of apples taken from storage by montly intervals were examined.According to the storage results, it is determined that Granny Smith, Imparatore and Idared apple varieties can be stored at 0 Ctemperature and 90-95%relative humidity for 5-6 months

Environment-Induced Changes in Selective Constraints on Social Learning During the Peopling of the Americas

The weaponry technology associated with Clovis and related Early Paleoindians represents the earliest well-defined evidence of humans in Pleistocene North America. We assess the technological diversity of these fluted stone points found at archaeological sites in the western and eastern halves of North America by employing statistical tools used in the quantification of ecological biodiversity. Our results demonstrate that the earliest hunters in the environmentally heterogeneous East used a more diverse set of points than those in the environmentally homogenous West. This and other evidence shows that environmental heterogeneity in the East promoted the relaxation of selective constraints on social learning and increased experimentation with point designs

Statistical Analysis of Paradigmatic Class Richness Supports Greater Paleoindian Projectile-Point Diversity in the Southeast

Ronald Mason\u27s hypothesis from the 1960s that the southeastern United States possesses greater Paleoindian projectile-point diversity than other regions is regularly cited, and often assumed to be true, but in fact has never been quantitatively tested. Even if valid, however, the evolutionary meaning of this diversity is contested. Point diversity is often linked to Clovis origins, but point diversity could also arise from group fissioning and drift, admixture, adaptation, or multiple founding events, among other possibilities. Before archaeologists can even begin to discuss these scenarios, it is paramount to ensure that what we think we know is representative of reality. To this end, we tested Mason\u27s hypothesis for the first time, using a sample of 1,056 Paleoindian points from eastern North America ami employing paradigmatic classification and rigorous statistical tools used in the quantification of ecological biodiversity. Our first set of analyses, which compared the Southeast to the Northeast, showed that the Southeast did indeed possess significantly greater point-class richness. Although this result was consistent with Mason\u27s hypothesis, our second set of analyses, which compared the Upper Southeast to the Lower Southeast and the Northeast showed that in terms of point-class richness the Upper Southeast \u3e Lower Southeast \u3e Northeast. Given current chronometric evidence, we suggest that this latter result is consistent with the suggestion that the area of the Ohio, Cumberland, and Tennessee River valleys, as well as the mid-Atlantic coastal plain, were possible initial and secondary staging areas for colonizing Paleoindian foragers moving from western to eastern North America

The exceptional abandonment of metal tools by North American hunter-gatherers, 3000 B.P.

Most prehistoric societies that experimented with copper as a tool raw material eventually abandoned stone as their primary medium for tool making. However, after thousands of years of experimentation with this metal, North American hunter-gatherers abandoned it and returned to the exclusive use of stone. Why? We experimentally confirmed that replica copper tools are inferior to stone ones when each is sourced in the same manner as their archaeological counterparts and subjected to identical tasks. Why, then, did copper consistently lead to more advanced metallurgy in most other areas of the world? We suggest that it was the unusual level of purity in the North American copper sourced by North American groups, and that naturally occurring alloys yielded sufficiently superior tools to encourage entry into the copper-bronze-iron continuum of tool manufacture in other parts of the world

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

Possible origins of macroscopic left-right asymmetry in organisms

I consider the microscopic mechanisms by which a particular left-right (L/R) asymmetry is generated at the organism level from the microscopic handedness of cytoskeletal molecules. In light of a fundamental symmetry principle, the typical pattern-formation mechanisms of diffusion plus regulation cannot implement the "right-hand rule"; at the microscopic level, the cell's cytoskeleton of chiral filaments seems always to be involved, usually in collective states driven by polymerization forces or molecular motors. It seems particularly easy for handedness to emerge in a shear or rotation in the background of an effectively two-dimensional system, such as the cell membrane or a layer of cells, as this requires no pre-existing axis apart from the layer normal. I detail a scenario involving actin/myosin layers in snails and in C. elegans, and also one about the microtubule layer in plant cells. I also survey the other examples that I am aware of, such as the emergence of handedness such as the emergence of handedness in neurons, in eukaryote cell motility, and in non-flagellated bacteria.Comment: 42 pages, 6 figures, resubmitted to J. Stat. Phys. special issue. Major rewrite, rearranged sections/subsections, new Fig 3 + 6, new physics in Sec 2.4 and 3.4.1, added Sec 5 and subsections of Sec