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Researchers use a variety of target materials, and sometimes combinations of materials, in their archaeological experiments to examine thrust‐spear or projectile penetration, impact angle, durability, and other issues involving prehistoric hunting weaponry. This variety of target materials is beneficial to archaeological science in several ways, but it may also hinder the comparison of results because many of these target materials do not necessarily share similar physical properties. Here, we assess the penetration properties of four different target materials—store‐bought meat, clay, and two types of gelatin—via static penetration tests of a modern broadhead‐tipped arrow and a stone‐tipped projectile attached to an Instron Universal Materials Tester. Our analyses of load‐deflection curves, peak load, and work energy demonstrate how the four target materials are similar in some ways but different in others, which suggests that researchers may strategically employ one or several depending on the question asked or hypothesis tested. [ABSTRACT FROM AUTHOR]

Many factors governed the penetration efficacy of prehistoric projectile weaponry. Archaeologists broadly focus their efforts on understanding the effect of stone weapon tips because these specimens are often the only part of the weapon system that survives in the archaeological record. The tip cross‐sectional area (TCSA) and perimeter (TCSP) of stone weapon tips have been shown to correlate with target penetration depth. Here, using results from both static and dynamic penetration testing, we compare TCSA and TCSP against other tip geometry metrics: lateral surface area (LSA) and volume (V). Our analyses broadly show that using a single‐point geometry metric evaluated at multiple locations along the length of the point, or using multiple geometry metrics evaluated at a single location, better predicts required energy than using a single‐point geometry metric evaluated at a single location. Our results also show that in the case where a single geometry metric evaluated at multiple locations is used LSA provided the most robust prediction models. Finally, our results show that for the case where all geometry metrics evaluated at a single location are used the location that provides the most robust prediction model is dependent on how far the point penetrated the target. [ABSTRACT FROM AUTHOR]

Clovis groups, the first widely successful colonizers of North America, had a distinctive technology, whereby manufacturers removed flakes to thin the bases of their stone projectile points, creating “flutes.” That process is challenging to learn and costly to implement, yet was used continent-wide. It has long been debated whether fluting conferred any adaptive benefit. We compared standardized models of fluted and unfluted points: analytically, by way of static, linear finite element modeling and discrete, deteriorating spring modeling; and experimentally, by way of displacement-controlled axial-compression tests. We found evidence that the fluted-point base acts as a “shock absorber,” increasing point robustness and ability to withstand physical stress via stress redistribution and damage relocation. This structural gain in point resilience would have provided a selective advantage to foragers on a largely unfamiliar landscape, who were ranging far from known stone sources and in need of longer-lasting, reliable, and maintainable weaponry. [ABSTRACT FROM AUTHOR]

Lithic raw material differences are widely assumed to be a major determining factor of differences in stone tool morphology seen across archaeological sites, but the security of this assumption remains largely untested. Two different sets of raw material properties are thought to influence artifact form. The first set is internal, and related to mechanical flaking properties. The second set is external, namely the form (size, shape, presence of cortex) of the initial nodule or blank from which flakes are struck. We conducted a replication experiment designed to determine whether handaxe morphology was influenced by raw materials of demonstrably different internal and external properties: flint, basalt, and obsidian. The knapper was instructed to copy a "target" model handaxe, produced by a different knapper, 35 times in each toolstone type ( n = 105 handaxes). On each experimental handaxe, 29 size-adjusted (scale-free) morphometric variables were recorded to capture the overall shape of each handaxe in order to compare them statistically to the model. Both Principal Components Analysis (PCA) and a Multivariate Analysis of Variance (MANOVA) were used to determine if raw material properties were a primary determinate of patterns of overall shape differences across the toolstone groups. The PCA results demonstrated that variation in all three toolstones was distributed evenly around the model target form. The MANOVA of all 29 size-adjusted variables, using two different tests, showed no statistically significant differences in overall shape patterns between the three groups of raw material. In sum, our results show that assuming the primacy of raw material differences as the predominant explanatory factor in stone tool morphology, or variation between assemblages, is unwarranted. [ABSTRACT FROM AUTHOR]

The iconic Paleoindian projectile points of the northern portion of the North American Great Plains—Clovis, Folsom, Agate Basin, Plainview (Goshen), Hell Gap, Alberta, Scottsbluff, and Eden—span nearly 4,000 radiocarbon years. Here, we apply recent findings from experimental archaeology to a database of 343 Paleoindian points to better understand how well these point types potentially functioned relative to each other in terms of penetration. Given that tip cross-sectional area (TCSA) and tip cross-sectional perimeter (TCSP) inversely correlate with penetration depth, we measured and analyzed these two attributes on each specimen in our database. Our results indicate significant differences in the Paleoindian point types' tip cross-sectional geometries, suggesting that these points were not equally effective at penetration and that there is not a progressive trend in penetration effectiveness from Early to Late Paleoindian times. We conclude with a discussion of hypothetical Paleoindian point evolution and the reasons for the possible selection for or against penetration. The results speak to the assessment of archaeological and ethnographic technologies with full knowledge of their performance potential as gleaned from experimental archaeology. Such knowledge will help anthropologists propose more robust hypotheses involving the evolution of technology and culture, both past and present. [ABSTRACT FROM AUTHOR]