Fishtail Points Research Articles

Mobility and raw material procurement by Fishtail people in Uruguay: Evaluation of silcrete long distance transport between campsites and outcrops during the late Pleistocene (ca. 12,900–12,250 cal BP)

Lithic artifacts from late Pleistocene manufactured in silcrete are used to understand Fishtail behaviors linked to mobility, land use and raw material acquisition during early prehistory in Uruguay. The data analyzed here include three categories of silcrete evidence: (1) a database of Fishtail points, (2) regional outcrops of these lithic resource, (3) debitage and unifacial tools from campsites. We calculated the cumulative cost of movement between campsites and the nearest lithic resources in space, located within the silcrete area, the distances involved in such movements, and the possible connection routes between campsites and silcrete resources. We analyzed the raw materials, density and spatial distribution of Fishtail points, and generated a Predictive Model of Transit Pathways. The results obtained indicate that silcretes were transported over long distances in mobility networks by an extensive Paleoamerican social landscape from outcrops located in the western and southwestern to campsites in northwestern Uruguay at distances ranging between ∼ 179 and 482 km. This new data confirms long distance displacements, the high social value, and the preference of this lithic resource for the production of tool assemblages by the Fishtail peoples of Uruguay.

Abrigo 1, Cerro El Sombrero: An Early Site in Eastern Argentina

ABSTRACT Late Pleistocene human occupations are well represented in the Tandilia Range, Argentine Pampas. Abrigo 1 is a small shelter in close relation to the main and better-known site on the hilltop of Cerro El Sombrero, with both sites including Fishtail points. The oldest levels at the shelter dated to 13,000–12,000 calendar years ago and yielded two Fishtail points. This paper deals with the analysis of the sedimentary context, stratigraphy, artifact distribution, and site formation processes at Abrigo 1. The sedimentary record is dominantly composed of geogenic sediments with a minor participation of anthropogenic material, mainly lithic artifacts. The geogenic input includes sediments coming from the physical and chemical weathering of the rockshelter’s quartzites and windblown sediments. Pedogenesis is the prevailing site formation process. Artifact distribution, the homogeneity of the assemblage, and refitting are considered relevant to assess site integrity. The results are compared to other early cultural contexts of the immediate vicinity.

An Automatic Recognition Method for Fish Species and Length Using an Underwater Stereo Vision System

Developing new methods to detect biomass information on freshwater fish in farm conditions enables the creation of decision bases for precision feeding. In this study, an approach based on Keypoints R-CNN is presented to identify species and measure length automatically using an underwater stereo vision system. To enhance the model’s robustness, stochastic enhancement is performed on image datasets. For further promotion of the features extraction capability of the backbone network, an attention module is integrated into the ResNeXt50 network. Concurrently, the feature pyramid network (FPN) is replaced by an improved path aggregation network (I-PANet) to achieve a greater fusion of effective feature maps. Compared to the original model, the mAP of the improved one in object and key point detection tasks increases by 4.55% and 2.38%, respectively, with a small increase in the number of model parameters. In addition, a new algorithm is introduced for matching the detection results of neural networks. On the foundation of the above contents, coordinates of head and tail points in stereo images as well as fish species can be obtained rapidly and accurately. A 3D reconstruction of the fish head and tail points is performed utilizing the calibration parameters and projection matrix of the stereo camera. The estimated length of the fish is acquired by calculating the Euclidean distance between two points. Finally, the precision of the proposed approach proved to be acceptable for five kinds of common freshwater fish. The accuracy of species identification exceeds 94%, and the relative errors of length measurement are less than 10%. In summary, this method can be utilized to help aquaculture farmers efficiently collect real-time information about fish length.

Changes in projectile design and size of prey reveal the central role of Fishtail points in megafauna hunting in South America

Fishtail projectile points are the earliest widespread projectile type in South America, and share chronology and techno-morphology with Clovis, the oldest North American projectile type. Both were temporally associated with late Pleistocene megafaunal extinctions. Although the elusive direct evidence of human exploitation of megafauna in South America had kept Fishtails out of the extinction debate, a recent paper showed a strong relationship between the temporal density and spatial distribution of megafauna and Fishtail projectile points, and proposed that this weapon was designed and used for megafauna hunting, contributing to their extinction. If so, this technology must be distinctly different from post-FPP technologies (i.e., early Holocene projectile points), used for hunting smaller prey, in terms of distribution and functional properties. In this paper, we explore the changes in projectile point technology, as well as the body mass of potential megafaunal prey, and show that Fishtails were strongly related to the largest extinct megafaunal species.

Recycled Fishtail Points in the Argentinian Pampa: Everyday Tools on Distinctive Paleoamerican Objects?

ABSTRACT In this paper, we present the case of recycled Fishtail points from a late Pleistocene site in the Pampean Tandilia ranges, Argentina. Detailed descriptions of the recycled tools are integrated with previous breakage and fatty-acids analysis. We assess if the practice of recycling was related to a specific task, a conservative strategy, functional reasons, and if other non-economic reasons may have played a significant role. Results show a marked selection of certain fragments to manufacture burin-like tools and a few other tool types. We propose that recycling of Fishtail points played a role in making and repairing weapons, and that different factors must be considered to explain the reasons behind this practice.

INITIAL HUMAN COLONIZATION OF THE AMERICAS, REDUX

ABSTRACTThe study of the peopling of the Americas has been transformed in the past decade by astonishing progress in paleogenomic research. Ancient genomes now show that Native American ancestors were formed in Siberia or the Amur region by admixture of ca. 15–30% Ancient North Eurasian genes with those of East Asians. The Anzick infant, buried with Clovis bifaces at 12,900 cal BP, belonged to a group that was ancestral to later Native Central and South Americans. Fishtail points, derived from Clovis, mark the arrival and rapid expansion of Clovis-descended Paleoindians across South America, also evident in the sharp increase of radiocarbon dates, continent-wide, at 13,000–12,500 cal BP. In both North and South America, extinction of most genera of megafauna was virtually simultaneous with Paleoindian expansion. Human hunting must have been involved, perhaps in concert with other indirect impacts. Contrary to the alternative bolide impact theory, there is no evidence of a dramatic human population decline after 12,800 cal BP. Ancient genomes show that divergent lithic traditions after 13,000 cal BP need not be attributed to a separate Pacific Rim migration stream. Several recent finds raise the possibility that pre-Clovis people might have reached the Americas before 20,000 cal BP, but these precursors must have either failed to thrive, or were ultimately replaced by proto-Clovis or Clovis people. Consilient paleogenomic and archaeological data indicate that initial colonization by Paleoindian ancestors of living Native Americans occurred after 14,500 cal BP.

Late Pleistocene South American megafaunal extinctions associated with rise of Fishtail points and human population

In the 1970s, Paul Martin proposed that big game hunters armed with fluted projectile points colonized the Americas and drove the extinction of megafauna. Around fifty years later, the central role of humans in the extinctions is still strongly debated in North American archaeology, but little considered in South America. Here we analyze the temporal dynamic and spatial distribution of South American megafauna and fluted (Fishtail) projectile points to evaluate the role of humans in Pleistocene extinctions. We observe a strong relationship between the temporal density and spatial distribution of megafaunal species stratigraphically associated with humans and Fishtail projectile points, as well as with the fluctuations in human demography. On this basis we propose that the direct effect of human predation was the main factor driving the megafaunal decline, with other secondary, but necessary, co-occurring factors for the collapse of the megafaunal community.

Raw materials and functional designs of Fishtail projectile points from southern Brazil

This study analyses the lithic landscape and the selection of rocks used to manufacture Fishtail points (FP) in southern Brazil, their designs, and some functional aspects. In order to identify the offer of lithic resources, we carried out several surveys throughout 15 months in 47 counties in the Southern Brazil covered by the Botucatú - Serra Geral Vulcano Sedimentary Complex. The lithic composition of numerous hill slopes, fallen rocks, and accumulations of pebbles and boulders in the riversides was evaluated. The results show that basalts (including a small proportion of andesites and rhyodacites-rhyolites), and silicified sandstones, are ubiquitous in the landscape. Conversely, non-translucent cherts are scarce, so their acquisition would have been time-consuming. However, these local cherts were the rocks mostly used to manufacture these points, being another example of the selectivity for high quality rocks by Paleoamerican hunter-gatherers. The same cherts selected in southern Brazil to produce the FP were used to manufacture other point-types by local hunter-gatherers of the early and middle Holocene grouped in the so-called “Umbú Tradition”. Not a single FP of the entire collection analyzed here was made from silicified limestones, which is one of the most common raw materials among the Uruguayan FPs, nor were they made from quartzites as were most of the FPs of the Pampean plains.
 Regarding to the designs of these projectiles, some morphotypes appear to have been designed to produce multiple injuries through successive thrusts and withdrawals in the bodies of the prey, while in others, the design seems to have favoured penetration and fixation on the prey, suggesting in this case, a single shot technique for each projectile. As the maintenance process unfolded, especially for points below ~ 80 mm in length, they show features that negatively impacted their efficiency, including distinct asymmetries, somewhat open front angles, a decrease in the cutting perimeter and cross-sectional area, an increase in the bevel angle of the blade edges, and a tendency to a conical cross-section. Behaviours intended to counteract these problems were maximizing the length of the leading edge, maintaining the symmetry and the triangular blade resting on straight shoulders, and maintaining the aerodynamic properties as much as it were possible, in order to improve their lethality and the fixation capacity.
 Beyond these rejuvenation processes, three different morphotypes of points appear to be included within the sample. The first includes points over 120 mm and ~ 80 g in weight, with triangular or slightly lanceolate limbs, which mostly present straight shoulders, but there are also examples of rounded shoulders. The second design corresponds to projectiles between 110 and 87 mm and ~30 g in weight, with triangular or slightly lanceolate blades and straight shoulders. The third design presents the classic shape of these projectiles, with a fish silhouette, with maximum lengths below 90 mm, with a more robust and conceptually different design, where the angles of the edges of the blades and of the shoulders are equal, perhaps with the intention to facilitate the spear withdrawal to produce multiple injuries.

The First Fishtail Point Find in Piauí State, Northeastern Brazil: Significance and Hypothesis

ABSTRACT Here we report a newly discovered Fishtail, or Fell 1, projectile-point type, from Coronel José Dias, southern Piauí, northeastern Brazil. It is an almost complete bifacial piece on light local silex. In Brazil, Fishtail points have not been previously reported in detail north of the 22° S parallel. Hence, this new evidence importantly establishes human occupation of extreme northeast of South America during the Pleistocene-Holocene transition.

Late glacial and Early Holocene migrations, and Middle Holocene settlement on the lower isthmian land-bridge

Archaeological evidence from Late Pleistocene sites in South America indicates that human populations moved into and through the lower isthmian land-bridge by at least 16,000 cal BP. Extrapolations from DNA analyses of ancient and current populations are broadly supportive. The only archaeological trace of the earliest movements into the land-bridge consists of two point fragments similar to El Jobo points dated at Taima Taima to ca 15,800 cal BP. The earliest robust evidence of occupation on the land-bridge is the widespread presence of stone tools of the Clovis and Fluted Fishtail Point traditions. The striking similarities between the lithic reduction sequences leading to finished Clovis points in North America to the sequences in evidence at three quarry/workshop sites on the land-bridge (La Mula West and Nieto in Panama and Finca Guardiria [Turrialba] in Costa Rica) suggest a rapid demographic expansion of Clovis populations onto the land-bridge by 13,000 cal BP. The Fluted Fishtail Point Tradition may have overlapped, but most likely postdated the Clovis Tradition among land-bridge populations during the terminal Pleistocene ca 12,500–11,700 cal BP. A series of stemmed and/or tanged points characterized the Early Holocene (11,700–8200 cal BP) lithic assemblages. Point styles, and settlement densities and distributions showed little change during the Late Pleistocene and beginning of the Early Holocene. The appearance of domesticated crops and plant processing tools midway through the Early Holocene initiated a series of changes that led to larger and less mobile populations increasingly dependent on domesticated plants and thus bound to their houses, gardens and fields. Coincidently, bifacial flaking was abandoned as a lithic reduction strategy over much of the lower isthmian land-bridge terrain. Sites with archaeozoological evidence for inshore and estuarine fishing and coastal invertebrate collection are visible in Pacific estuarine zones by 7650 cal BP and on one of the Pearl Islands in Panama Bay islands by 6235 cal BP, in the Middle Holocene (8200-4200 cal BP), but any earlier sites of this nature would lie underwater because post-glacial sea-level rise had not yet levelled off (Redwood, 2020).

Análisis espacial del sitio Amigo Oeste, Meseta de Somuncurá (Río Negro, Argentina)

En este trabajo analizamos las distribuciones espaciales de los artefactos líticos en Amigo Oeste, un sitio al aire libre ubicado en la región de la meseta de Somuncurá (Río Negro, Argentina). Una de las principales singularidades del sitio es que una gran proporción de las evidencias arqueológicas registradas consiste en Puntas Cola de Pescado (PCP), artefactos de diagnóstico asignados a la transición Pleistoceno-Holoceno, lo que demuestra su relevancia para el estudio del poblamiento temprano de las Américas. El sitio se extiende tanto en la cima como en la ladera sureste de un cerro de 84m de desnivel.El relevamiento de información espacial en este sitio se realizó mediante 292 unidades transectas y recolección puntual de artefactos registrados mediante GPS no diferencial y teodolito electrónico. Se recolectaron 2575 artefactos líticos entre núcleos, artefactos formatizados y artefactos no formatizados. Hasta el momento el sitio ha sido interpretado como un lugar de visualización para control del entorno (que pudo haber sido usado como campo de caza), donde se realizaron tareas de reequipamiento de PCP, así como otras actividades relacionadas con la cacería.Con el objetivo de explorar patrones espaciales en los indicadores de actividades realizadas en el sitio, los datos generados en trabajos previos (la ubicación de los artefactos y los atributos generados desde el punto de vista tecno-morfológico y morfológico-funcional, así como información ambiental) se integraron en un Sistema de Información Geográfica, y se realizó un análisis espacial exploratorio para definir estadísticamente la existencia de agrupaciones en los artefactos, en los atributos asociados a ellos, así como el número de agrupaciones y su ubicación. Este trabajo permitió lograr un mayor conocimiento sobre las áreas de actividad en el sitio y en su entorno inmediato.

Life history or stylistic variation? A geometric morphometric method for evaluation of Fishtail point variability

Fishtail points are considered an indicator of the presence for one of the earliest and most successful human adaptations during the late Pleistocene in South America (~12,900–12,200 cal BP). Although these points display a wide range of variability both in size and shape, previous studies are mainly technological and descriptive observations. No efforts have been made to propose qualitative and quantitative indexes in order to understand how the rejuvenation/resharpening process may have affected the observed variability. In this paper, we explore different analytical methods to understand the rejuvenation process, explain the morphological variability of the Fishtail points and evaluate them from the perspectives of geometric morphometrics and multivariate statistics. This analysis allows us to generate new fresh interpretations and ideas about the rejuvenation of points. The combination of 2d geometric morphometrics, linear measurements, and multivariate regression, supports the hypothesis that the continuum of shape variation is explained by the long life history trajectories of the Fishtail points.

High resolution AMS 14C dates for late Pleistocene Fishtail technology from the Tigre site, Uruguay river basin, South America

The basin of the Uruguay middle river has contributed important advances related to knowledge of the early settlement of southeastern South America. This paper presents recent progress of the research on the Paleoamerican period that is being carried out in the Tigre site (Uruguay), where a cultural component with Fishtail points, bifaces, preforms and other artifacts dated at ∼ 12,800 and 12,200 cal BP was found. The presence of silicified limestone (silcrete) in the Tigre site indicates mobility ranges of 190–350 km to obtain this lithic resource. The data presented here allow to have an accurate discussion of the chronological period occupied by Fishtail groups on the plains of Uruguay; and to recognize the late stages of the Fishtail point manufacturing process used by these human groups, one of the most successful adaptations during the end of the Pleistocene in South America.

Phylogenetic analysis of stemmed points from Patagonia: Shape change and morphospace evolution

This work is focused in the study of Patagonian lithic projectile points shape variation from a phylogenetic perspective pursuing three main aims: first, generate a model of projectile point shape diversification and morphospace evolution; second, estimate shape variation through time, and finally, assess the robustness of previous results using the same methods but in a larger sample with better spatial coverage. A previous work using geometric morphometric and cladistic methods suggested a pattern of general morphological diversification across Patagonia related, at least in part, to the spatial distance between cases, distinguishing two main clades in northern (43-45° S) and southern (50-52° S) Patagonia. In the present work to study this pattern in a more detailed level, a sample of ca. 1200 projectile points was used to obtain statistically different morphological classes performing unsupervised K-means searching. Shape characters were used to describe the different taxonomic units and to perform the phylogenetic analysis (through the Neighbor Joining and Maximun Parsimony methods) using as an ancestor the earliest point type known to the region (Fishtail point). The new results suggest that projectile points with longer and narrow blades and smaller stems evolved later in Patagonia and occupy a different sector of morphospace that could be related to the emergence of different technical systems, like the bow and arrow. However, these results do not support the previous ones of a projectile point diversification pattern mediated by spatial distance, maybe due to the reduction of contrast between the extreme north and south of Patagonia by the larger spatial coverage used in the present analysis.

Fell Point Technology from Mendoza Province in Western Argentina

ABSTRACTOne of the most iconic remains from the South American Paleo-American record is the so-called Fishtail, or just “Fell” projectile point, a distinctive artifact that stands out due to its wide distribution from southern Mexico to southernmost South America. This research brief informs on new data and observations on two Fishtail points found in Mendoza province in western Argentina. Detailed techno-morphological observations showed two shape variations; one was comparable to the so-called stereotype, and the other with the lanceolate variant recorded among this kind of diagnostic artifact. Stratigraphic contexts spanning the Fishtail point's age of ∼11,000–10,000 radiocarbon years ago have been found in the region. This fact suggests that during the last millennium of the Pleistocene, hunter–gatherers using Fishtail points in their weaponry were foraging in the landscape in the lowlands of the southern Andean mountain range in western South America.

LUMINESCENCE DATING OF LATE PLEISTOCENE AND HOLOCENE SEDIMENTS IN URUGUAY

The archaeological record in the Negro River in central Uruguay Republic is remarkable for its richness, including the presence of a significant number of Paleoindian fishtail points. As part of ongoing research on the earliest human occupations in this region, luminescence dating is applied to develop a terminal Pleistocene-Holocene regional chronology. Eight ages were derived from six samples taken from sedimentary fluvial deposits from two sites near the city of Paso de los Toros. The resulting dates span 11.8 and 1.04 ka corresponding to the Late Pleistocene and the whole Holocene. Because the chronology of the sedimentary sequences spanning these ages is poorly known, the presented results become a significant contribution to the construction of a chronostratigraphy sequence in the area. The results also show how single-grain dating can distinguish different components of mixed assemblages.

Assessing Fishtail points distribution in the southern Cone

This paper discusses possible causes affecting the distribution of Fishtail points in the southern Cone. This distribution is discontinuous, with large territories without diagnostic remains and areas where sites and points are concentrated. Also, most of the sites with this type of points exhibit few specimens, with remarkable exceptions in Uruguay, the Argentinian Pampa and Patagonia and southern Chile.We present thoughts arising from long term research in the central east Tandilia ranges, in the Argentinian pampas with information relevant to this discussion. We call the attention to the importance past social practices have in conforming current point distribution together with the history of research and site visibility. This issue is then considered in the broader regional scale. It is concluded that the discontinuous distribution observed is due to factors inherent to both the original occupations and to current research.

The Anzick genome proves Clovis is first, after all

The close relatives who buried the Anzick infant ca. 12,800 cal BP made classic Clovis tools and were unequivocally the lineal genetic ancestors of all the living Native peoples of southern North America, Central America, and South America. Clovis-derived Fell I fishtail points track the rapid southward migration of this ancestral population all the way to Tierra del Fuego. Any hypothesized earlier populations, if they (improbably) ever existed, must have been replaced or genetically swamped by these Clovis descendants.

Fishtail points from the Pampas of South America: Their variability and life histories

Fishtail points (FTP) related to the terminal Pleistocene peopling of the South American continent present morphological, technological and functional variability. We discuss a collection of FTP recovered from central east Tandilia Range in the Pampas of Argentina. We do this by exploring the life histories of a set of 97 FTP, assessing aspects of production, use and discard through morphological, macro-fracture, and fatty acids and sterols analysis. We identify four categories: miniatures, “atypical FTP”, medium-sized and large points. Although possibly all were related to the realm of hunting, only medium and large points have clear indications of use as parts of weapons. Transformation due to maintenance, impact or recycling indicates their longevity and the complexity of their life histories. Miniatures are considered representations of full sized points and large points also possibly held a special status, requiring great flintknapping skill. As artifacts covering different roles and used in different social practices repeat the FTP outline, we sustain this shape must have held some significance for the people who produced and used them. Other aspects related to FTP use lives which probably were laden with meaning are the choice of colored and translucent toolstone and their intentional place of discard.

Paleoamericans in Northeast Argentina

In this paper, we present a brief synthesis of the record of Fell or Fishtail points found in northeast Argentina, including the first two records for Misiones province. To date, 11 pieces have been identified in the region, which demonstrate techno-morphological similarities with specimens recovered in different areas of South America, which are linked to Paleoamerican groups of the Pleistocene-Holocene boundary. Although these points are still scarce in this area, this is probably due to the lack of research and issues related to archaeological visibility. These new records increase the density of findings of these early hunter-gatherers on the South American Atlantic slope.