Final Late Holocene Research Articles

Late-Holocene stability and recent changes in small mammal communities in north-central Andean forests of Patagonia

Past and current climatic and environmental changes have contributed to configure actual species distributions and abundances. Knowing their evolution over time allows discrimination between natural and anthropogenic causes in current composition of faunal communities. We evaluate the changes in small mammal assemblages from the north-central Patagonian Andean forests since the Late-Holocene to recent times and their relationship with the environmental modifications driven by human activities. A bone sequence from Población Anticura archaeological site (lower Manso river valley, Río Negro province, Argentina) was studied, which encompasses a time span from the early Late-Holocene (3350 ± 100–2270 ±80 years BP) to final Late-Holocene (1420 ± 70–530 ±50 years BP) and Historical times (480 ± 70–280 ±40 years BP). The species composition indicates that forest environment established in the area from at least the Late-Holocene (dominance of Loxodontomys micropus, with subordinate frequencies of Abrothrix olivacea, A. hirta, Geoxus valdivianus, Irenomys tarsalis, and Paynomys macronyx), with patches of (or near to) open environments (presence of Reithrodon auritus and cavids). It is remarkable the presence of cavids, which increased their abundance in the sequence towards Historical times but disappeared nowadays. The low frequencies (<10%) of the rodent Oligoryzomys longicaudatus along the entire sequence is also relevant, since this rodent is the reservoir of the Andes strain of the Hantavirus (ANDV), which causes pulmonary syndrome. This mouse dominates the small mammal assemblages from forests and ecotonal shrublands of northwestern Patagonia (abundances exceed 50% in owl pellets recently collected from the study area). Current configuration of forest and ecotonal assemblages, particularly the high abundance of O. longicaudatus, should be mainly linked to anthropogenic causes, including the introduction of cattle, land clearing, and the advance of introduced plant species such as the sweet briar ( Rosa eglanteria). Particularly, this exotic shrub offers shelter and additional food for O. longicaudatus, turning their shrublands into spaces of high epidemiological risk.

Using mixing models to study human paleodiets in central‐western Santa Cruz (Argentina) during Late Holocene

AbstractDuring the final Late Holocene, there was a socio‐economic reorganization among the people in the central‐western of Santa Cruz, Argentina. Analysis of bone collagen revealed that hunter–gatherer groups maintained a consistent diet rich in steppe animal protein for the past 3000 years. However, there was a change in bioapatite δ13C values in the last 1000 years, indicating a shift in the whole diet that was not reflected in the protein component. This article seeks to evaluate the differential consumption of resources over time and between sexes among hunter–gatherer populations in the region. A total of 39 adult individuals of both sexes, recovered from stone burial structures with different chronologies, were analyzed. Quantitative diet reconstruction was achieved through the use of the Bayesian mixing model known as Food Reconstruction Using Isotopic Transferred Signals (FRUITS). The results show that the guanaco (Lama guanicoe) was the most consumed animal throughout the studied period, considering both temporal and sex differences. Additionally, there is an increased importance of plant consumption in the last millennium, particularly among females. However, this can be the result of overrepresentation of this resource in our food web samples, due to the impossibility of resolving the origin of the carbon for the formation of bioapatite values.

Size estimation based on Genidens barbus and Micropogonias furnieri otoliths. Exploring Late Holocene euryhaline fish capture techniques in the eastern Pampa–Patagonia transition, Argentina

Sea catfish (Genidens barbus) and whitemouth croaker (Micropogonias furnieri) were the most marine euryhaline species exploited by hunter-gatherers during the final Late Holocene along the coastal fringe of the eastern Pampa–Patagonia transition (Argentina). In the lower basin of the Colorado River, zooarchaeological evidence recovered from the San Antonio archaeological locality indicates prevalent fish consumption. However, no specific technology related to fishing has been recovered as part of the archaeological assemblages, hence strategies and techniques of fish capture remain unknown. The aim of this paper is to estimate the size of both species through archaeological otolith measurements to evaluate possible fish capture techniques. The analyzed sample is made up of 117 otoliths of whitemouth croaker and 863 of sea catfish. The estimated size of G. barbus individuals is between ca. 240 and 730 mm, which indicates the presence of juveniles and adults. In the case of M. furnieri, the estimated size range of individuals is ca. 350–750 mm, which indicates the representation of adult specimens. Based on the diversity of sizes represented in both species, their ethology, and the geomorphological characteristics of the study area, it is proposed that the fish could have been caught with either nets or bare hands through nonselective mass trapping strategies during the spring–summer season.

Oxygen isotopes and human mobility in Middle and Late Holocene hunter-gatherer groups from the eastern Pampa-Patagonia transition (Argentina)

This work seeks to explore human mobility in the lower course of the Colorado River (Argentina) during the Middle and Late Holocene (ca. 5900-250 years BP) through the analysis of stable oxygen isotopes (δ18O) of bone bioapatite. The δ18O values are interpreted and compared with those from North Patagonia and Western Pampas to evaluate mobility at a regional scale. Forty-one adult individuals of both sexes from 12 archaeological sites were analyzed. δ18Oc values were transformed into drinking water (δ18Odw). The results were compared with the hydrological baseline generated for central-eastern North Patagonia and real rainfall data and predictive rainfall models. ẟ18Oc values indicate higher values in individuals corresponding to Middle Holocene (−0.7‰) compared with the Initial Late Holocene (−3.1‰) and Final Late Holocene (−2.3‰) and statistically significant differences between Middle Holocene and Late Holocene. Based on the δ18Odw values, 17.1% (7/41) correspond to hydrologic zones defined for central-eastern North Patagonia, and 48.8% to the real and predictive rainfall models. Although differences in δ18Odw values are observed between the Middle and Late Holocene, it is not yet possible to propose precise human mobility geographical directions in the study area. Nevertheless, during the Late Holocene, the δ18Oc values showed that individuals buried in the study area could have shared some water sources with those from Western Pampas and nearby sectors from Northeastern Patagonia, such as the lower course of the Negro River.

Los restos faunísticos del sitio arqueológico Tembrao (provincia de Río Negro, Argentina)

En este trabajo se presenta el análisis de los materiales faunísticos del sitio Tembrao, ubicado en un pequeño valle al pie de la meseta de Somuncurá (sur de la provincia de Río Negro). Un fechado realizado sobre restos faunísticos ubica la ocupación del lugar en el Holoceno tardío final. El conjunto está conformado principalmente por restos óseos de mamíferos, entre los que predominan los de artiodáctilos. Se propone que los guanacos habrían sido la presa principal de los cazadores recolectores pre-hispánicos, mientras que los restos de ovejas fueron ingresados por las ocupaciones modernas del paraje Tembrao. Se discute la disponibilidad de recursos faunísticos en cercanías del sitio, especialmente de guanacos sobre la meseta de Somuncurá, y las implicancias de la presencia de elementos foráneos (valvas de almejas fluviales y de moluscos marinos, y probablemente cáscaras de huevos de Rhea americana). En base al análisis se infiere un patrón de subsistencia basado en pocas especies, similar al de otras regiones mesetarias de Norpatagonia y claramente diferenciado de aquel del litoral marino y de los valles fluviales.

Patterns of dietary diversity in Holocene north-west South America: new insights from Bayesian stable isotope mixing models

For two decades, stable isotope studies have documented palaeodietary transitions in the Sabana de Bogotá region of north-west South America. Using traditional and Bayesian stable isotope mixing models, this article investigates the contribution of different resources to Holocene human diets. Temporal patterns include dietary emphases on plants during the Early and Middle Holocene, on maize horticulture through the initial Late Holocene and on maize/tuber agriculture during the final Late Holocene; animal protein apparently contributed little across all periods. These results suggest that the management and selection of diverse plants occurred early, and the later emphasis on maize raises universal questions about the role of agriculture in cultural change and social differentiation.

Guanaco hunting and Llama herding in the South-Central Andes (3000-900 BP): An osteomorphometrical approach

This paper aims to contribute to the study of the subsistence of human populations from the northern part of the Quebrada de Humahuaca (Northwestern Argentina –NWA-) between 3000 and 900 years BP, through the morphological and morphometric analysis of bone remains from large-sized camelids. The contribution of two complementary strategies -guanaco (Lama guanicoe) hunting and llama (Lama glama) herding- to the diet of those populations throughout the late Holocene is assessed. In order to achieve this, the first and second anterior and posterior phalanges are analyzed through both traditional morphometric (TM) and two-dimensional geometric morphometric (2D GMM) techniques. The sample is composed of 398 elements from 49 modern llamas and guanacos, and 36 elements from archaeological camelids recovered from the Antumpa, Cóndor II and Casas Grandes sites. We discuss the problem of the taxonomic identification of South American large-sized camelids with a novel methodology and we contribute relevant zooarchaeological information for a poorly studied geographical setting. Results indicate that llama herding prevailed throughout the late Holocene (4000-300 AP), although TM techniques showed a slight increase in guanaco hunting during the final late Holocene (1100-300 BP) and GMM showed a constant frequency of representation. The trends and variations thus identified would respond to both anthropic and local ecological factors.

A paleogenetic perspective of the Sabana de Bogotá (Northern South America) population history over the Holocene (9000–550 cal BP)

On the basis of distinct lines of evidence, detailed reconstructions of the Holocene population history of the Sabana de Bogotá (SB) region, Northern South America, have been performed. Currently, there exist two competing models that support temporal continuity or, alternatively, divergence. Despite recent bioarchaeological and isotopic research that lends support to the population discontinuity model, several discrepancies remain, calling for other kinds of evidences to be explored for a more detailed picture of Holocene biocultural evolution. In this study, 15 new complete mitochondrial genomes obtained from 30 individuals recovered from several archaeological sites spanning from the late Pleistocene (11,950–11,262 cal BP) until the initial late Holocene (2941–2752 cal BP) along with published data (n = 20) from the region dating ~9000–540 cal BP were used to investigate diachronic genetic change. Genetic diversity and distance indices were calculated, and demographic models tested in an approximate Bayesian computation (ABC) framework to evaluate whether patterns of genetic affinities of the SB prehispanic populations support genetic continuity or discontinuity. The results show that mitochondrial genomes of the complete dataset fall within the Native American haplogroups A2, B2, C1b, D1 and D4h3a. Haplotype and nucleotide diversity declined over time with further evidence of genetic drift and remarkable reduction of genetic diversity during the final late Holocene. Inter-population distances and the exact test of population differentiation, as well as demographic simulations show no population differentiation and population continuity over time. Consequently, based on the analyzed data, we cannot reject the genetic continuity in the SB region as a plausible population history scenario. However, the restriction of the analyses to the Hyper Variable Region 1 of the mitochondrial genome, and the very low sample size both constitute significant limitations to infer evolutionary history.

First analysis of mitochondrial lineages from the eastern Pampa–Patagonia transition during the final late Holocene

Studies on population genetics have become highly relevant for understanding the evolutionary history of human settlement in southern South America. The eastern Pampa-Patagonia transition is an area that stands out due to its complex population dynamics, especially during the last about 1,000 years BP. The aim of this work is to characterize the maternal lineages of individuals buried in the Paso Alsina 1 archaeological site (ca. 500 years BP) through the analysis of mitochondrial genetic variability, in order to discuss the population models previously proposed for the southern cone of South America. Mitochondrial HyperVariable Region I sequences were analyzed on teeth belonging to 20 adult individuals. Statistical analyses were carried out to compare the interpopulation and intrapopulation molecular variability between the results obtained in this work and those previously published data from pre-Hispanic human groups. D1 haplotype network was constructed drawing from data on ancient and extant population group samples. Thirteen sequences (65%) were obtained from the 20 analyzed samples. The maternal lineages or subhaplogroups identified were D1g (69.24%), C1 (15.38%), D1 (7.69%), and D1j (7.69%). There was low haplotype variability within the site; some individuals could be matrilineally related. The subhaplogroups registered in Paso Alsina 1 site are in accordance with those reported for ancient and contemporary Patagonian populations. The results suggest that an initial nucleus of individuals carrying mostly subhaplogroup D1g settled in northern Patagonia, from which local diversity of this matrilineage could have arisen. The existence of gene flow in the final late Holocene with groups from Northern Andean Patagonia, as well as from Central Argentina, is proposed. The D1j variant probably developed in the latter region.

Taking care in prehistoric Latin America: A case study of care giving among hunter-gatherers in the Final Late Holocene

A published case of metastatic cancer from a hunter-gather group in pre-Columbian Argentina analysed the effects this illness would have on group dynamics. This essay uses the published details of the case study to analyse the possibility of care being provided to the dying individual. After a detailed discussion on the skeletal analysis and diagnosis offered by the original authors, this essay proposes that prior to his illness this individual would have been an active contributor to his group, likely involved in the transport and manipulation of stone. The functional impact the individual would have experienced as the result of his illness is discussed including the impact on the rest of his group, i.e. reduced contributions to group subsistence and inability to maintain residential mobility in a nomadic lifestyle. This essay argues that, based on the accommodation of their ill member by continuing to supply food despite his deteriorating state, this group of hunter-gatherers valued their individual members more so than their contribution to the group. This case study provides an insight into the value system of a pre-Columbian hunter-gatherer group outside of the more commonly examined subsistence activities, trading and burial practices.

Holocene population history of the Sabana de Bogotá region, Northern South America: An assessment of the craniofacial shape variation.

Several authors using multiple and independent lines of evidence investigating the biocultural continuity versus discontinuity in the Sabana de Bogotá region, in the eastern highlands of Colombia, have arrived at contradictory conclusions supporting either scenarios. This study analyzes the craniofacial size and shape variation of diachronic samples from the study region to test distinct population history scenarios that support continuity or, alternatively, divergence. A total of 92 adult skulls belonging to five chronological groups, ranging from c. 10,100 to 350 14 C YBP, were analyzed through Procrustean geometric morphometric techniques. Matrix correlation analysis, multivariate exploratory (PCA, FDA), and evolutionary quantitative genetic methods (R-matrix analysis and β-test) were used to study the diachronic craniofacial shape variation. A model that supports strong evolutionary diversification over the Holocene better explains the patterns of morphological variation observed. At least two periods of significant craniofacial size and shape change were detected: one during the middle to initial late Holocene transition (c. 4,000-3,200 14 C YBP) and other toward the final late Holocene (post-2,000 14 C YBP), which exhibit differences in the pattern and magnitude of cranial divergence. In addition, the differentiation viewed between early and mid-Holocene foragers could mark the initial entry of non-local populations into the region toward the beginnings of the middle Holocene. Distinct to previous investigations the present study supports a more complex regional population history where multiple population contractions/extinctions, dispersals and assimilations along with dietary adaptations took place during the last 10,000 years. These results are in agreement with the archaeological and paleoecological record which suggests marked periods of change rather than temporal stability.

Stable isotope evidence for dietary and cultural change over the Holocene at the Sabana de Bogotá region, Northern South America

The Sabana de Bogota in the northern Andes is an interesting region to investigate temporal patterns of dietary variation because it counts with a vast archeological and osteological record for the last 10,000 years. In this paper, stable isotope data of human archeological bone collagen and apatite were used to study the evolution of diet and major subsistence transformations taking place during the Holocene (∼9000–600 cal BP). Paleoenvironmental reconstructions and the isotopic ecology of the Sabana de Bogota were used as an interpretative baseline. Stable isotope measurements (δ13Ccol, δ13Cap, δ15N, and Δ13Ccol-ap) representing hunter-gatherers, horticulturalists, and agriculturalists (N = 134 individuals) were analyzed by using bivariate, regressional, and discriminant statistical techniques. Results show that early Holocene hunter-gatherers (9000–7000 cal BP) consumed mostly C3 vegetal resources locally available. In contrast, animal protein was less important. Middle Holocene hunter-gatherers (6000–4500 cal BP) continued with the food foraging pattern observed in the earlier counterparts and presented a slight increase in C3 animal protein intake. During the initial late Holocene ca. 4000 cal BP, important shifts in subsistence strategies occurred when populations presented a trend toward mixed C3/C4 diets, and by ca. 3500 cal BP, there is a clear signal of C4 crops (i.e., maize) consumption concomitant with the introduction of ceramic technology. During the final late Holocene (last 2000 cal years BP), intensive agriculture was adopted and humans presented relatively diverse diets integrated by C4 and C3 crops, C3-C4 feeding animals, and freshwater resources. Such dietary change coincides with an increase in sociopolitical complexity, population size, and a general decline in health.

Was There a Process of Regionalization in Northeastern Patagonia During the Late Holocene?

ABSTRACTThe objective of this article is to evaluate if changes in the social organization of hunter-gatherer groups from northeastern Patagonia (Argentina) during the Final Late Holocene (ca. 1000–250 years BP) may be understood as a regionalization process. A portion of this region, the lower course of the Colorado River, is taken as a case study. This arid/semi-arid area is part of an ecotone between the Pampas and northeastern Patagonia situated beside the Atlantic coast. Most of the evidence for occupation is concentrated in the Late Holocene, more precisely from 1000 to 250 BP. The archaeological record of this period indicates increased human population, along with a greater intensity of site occupation, the first systematic evidence of coastal occupation, reduced mobility and territoriality, diversification and intensification of subsistence practices, changes in the procurement and use of exotic raw materials, more complex funerary practices, and decreased circulation of specific images in portable artifacts. Based on these data, it is proposed that in some sectors of northeastern Patagonia during the Initial Late Holocene (3000–1000 BP) relatively open social networks operated, while for the Final Late Holocene (1000–250 BP) relatively closed social networks took their place within a framework of increasing regionalization. Factors relating to the latter are likely to have included demographic packing, spatial circumscription, territorial behaviors, and changes in population dynamics that were accompanied by social differentiation and more intense and competitive social interaction networks.

Étude technologique des collections lithiques de Nord-Patagonie Orientale (Argentine) pendant l’Holocène récent

The lower Colorado River is considered the geographical boundary between the Argentinean regions of Pampa and Patagonia. The aim of this study is to define the technological patterns of hunter-gatherer groups who inhabited the studied area during the Late Holocene (3000–250 BP). In order to do so, the nature and presentation of raw materials exploited is stated, and the different methods of débitage and economic analysis of the lithic assemblages are identified, within the theoretical and methodological approach of chaîne opératoire. The results allow concluding that during the Late Holocene the basis of technological knowledge is kept constant. The technological changes experienced in behavior toward the final Late Holocene (1000–250 years BP) are due to the choice among methods, materials, and types of instruments known and available, of those with proven efficacy, whose production was intensified in the last 1000 years BP. The behavioral changes linked to lithic technological system are accompanied by – or produced as a result of – reorganization of the social system as a whole.

Biological affinities and regional microevolution among pre-Hispanic communities of Colombia's Northern Andes.

Dental non-metric data were used to examine the biological continuity of pre-Hispanic peoples of Colombia's Northern Andes, including highland, lowland and coastal peoples. This report contributes to studies regarding the peopling of South America by establishing a benchmark comparison that includes pre-Hispanic populations of the Northern Andes. The sample consisted of a total of 583 individuals from 56 cemeteries ranging in time from the Early Holocene (10,000 BP) to the Final Late Holocene (500 BP). Permanent dentitions from individuals between 5 and 40 years of age were scored for 87 dental traits based on the ASUDAS. A divergence matrix was programmed using the Smith's Mean Measure of Divergence equation (MMD). Bartlett's adjustment and Ascombe transformation were considered into MMD calculations. Principal Coordenate analysis was applied based on MMD matrix scores. A clear group was found that associated Initial Late Holocene samples with Final Late Holocene samples. Early Holocene samples are very different to that, and Middle Holocene samples show as morphologically intermediate series. A comparison of the frequencies by time and period showed that a limited biological continuity existed. Interbreeding among initial populations of the same regions is expressed in similar frequencies of dental traits within Early Holocene and Middle Holocene samples. Early Holocene samples did not match with Sinodont pattern according to discriminant function analysis. These findings help us to better understand the settlement process of human groups in the Northern Andes and its relationship with migratory movements in South America.

Chronological distribution and disturbance factors to evaluate population dynamics in Western Pampas, Argentina

The radiocarbon chronology of the sites and cultural sequences is, at the regional level, a benchmark for evaluating different types of processes: cultural, demographic, taphonomic, environmental. Although it is assumed that chronological signal is closely related to the density and intensity of the processes of settlement, colonization, occupation and use of spaces and landscapes, this signal is mediated by many complex factors affecting its representation. In the case of the province of La Pampa (Argentina), which covers the western part of the Pampean region, where research data discussed in this paper are developed, several of these factors should act or be present. However, in the present state of research in the region it is possible to assess and discuss the significance of the radiocarbon signal, not only intra – regionally but in correlation with neighboring areas. In this paper a set of published radiocarbon dates (n = 64) is presented, that constitute all available Western Pampa published 14C dates. While still scarce and random, these dates establish that the timescale in which colonization events and use of regional space happened, archaeologically evaluated, covers a span comprised between mid-Early Holocene and final Late Holocene. The results will be discussed in comparative terms, into two scales: the intra and inter-regional and considering different type of archaeological sites.

The evolution of projectile points and technical systems: A case from Northern Patagonian coast (Argentina)

In this paper we present the results of the phylogenetic analysis of projectile points dating from the Middle-Late and final Late Holocene recovered from different sites along the coast of San Matías Gulf (Río Negro province, Argentina). In order to study the evolution of weapon systems we have used maximum parsimony phylogenetic reconstruction and tree based comparative methods. This allowed us to explore different evolutionary models addressing the technical systems used in the area.The results suggest the existence of a robust phylogenetic signal that gradually evolved into at least two technical systems. One of the most important results however, was the evidence of a certain morphological continuity. In turn this suggests that, rather than a direct replacement, there was an adaptation of propellant-type weapons towards the bow and arrow.We concluded that this pattern of metric and morphological continuity might be related to transitional forms between the different technical systems, with design types used in both systems. There would have been a degree of experimentation so as to produce performance effective projectile points, this would have occurred in a framework of trial and error in a context of low risk.

Radiocarbon trends in the Pampean region (Argentina). Biases and demographic patterns during the final Late Pleistocene and Holocene

This paper compiles a database of radiocarbon dates of archaeological sites that are currently available for the Pampean region. Based on the probability distribution of radiocarbon dates from this database, major temporal trends are defined, taphonomic and scientific biases are evaluated, and their implications for demography are suggested. Results indicate a continuous archaeological signal between ca. 14,500 and 100 cal BP. During the final Late Pleistocene and the Early Holocene, the archaeological signal is low in ca. 14,500–12,800 cal BP, and increases to a moderate and continuous signal in ca. 12,800–7500 cal BP. The archaeological signal for the former lapse correspond to the early peopling of the region and is related to the inhabiting and exploitation of key landforms (e.g., rock shelters, river valleys) and critical resources (e.g., lithic raw material, water). The low amount of available dates for the Middle Holocene (ca. 7400–3700 cal BP), and the associated archaeological signal would be due to the combination of various factors such as taphonomic biases, organization of prehistoric populations, and even a possible low population density. The obtained low but continuous signal for this period are discussed in the framework of the proposed models for the human occupation of the region suggesting that a hypothesis about population extinctions and disruptions processes could not be sustained. Finally, during the Late Holocene (from 3700 to 100 cal BP) human occupations are recorded in all the micro-regions. Regardless of biases, this signal is interpreted as an increase in demographic density at a regional level.

Resultados preliminares del sitio Zoko Andi 1. Aportes para la arqueología del curso inferior del río Colorado (Provincia de Buenos Aires)

El objetivo de este trabajo es presentar la cronología y las principales tendencias de los análisis geoarqueológicos, zooarqueológicos, de la tecnología lítica y de los entierros humanos recuperados en el sitio arqueológico Zoko Andi 1 (Pdo. de Patagones). Éste se localiza en una duna, sobre la margen derecha del curso inferior del río Colorado. Se obtuvieron nueve fechados radiocarbónicos provenientes de especímenes faunísticos, restos óseos humanos y carbón que ubican la cronología del sitio entre ca. 1500-400 años AP. Las dataciones obtenidas, en conjunción con los aspectos estratigráficos identificados, indican la existencia de al menos dos lapsos de ocupación. El primero de ellos se ubica en torno a los ca. 1500-1300 años AP (Holoceno tardío inicial), mientras que el otro se localiza en ca. 800-400 años AP (Holoceno tardío final). En este sentido, se trata del primer sitio del área en cuya secuencia se distinguen dos componentes que se corresponden con los dos bloques temporales del Holoceno tardío. Los resultados obtenidos hasta el momento en las distintas líneas de análisis se ajustan parcialmente a las tendencias propuestas en los modelos formulados para el área y son brevemente discutidas en este trabajo.

Mortality Profiles of Hunter-Gatherer Societies: A Case Study from the Eastern Pampa-Patagonia Transition (Argentina) During the Final Late Holocene

The objectives of this work are to present a set of methodological procedures to analyse commingled bone assemblages (e.g. secondary burials), in order to build the mortality profile of the Paso Alsina 1 site and discuss the obtained age at death distribution in a context of hunter-gatherer populations that inhabited the eastern Pampa–Patagonia transition (Argentina) during the Final Late Holocene. The Paso Alsina 1 site is a formal disposal area of inhumations composed by multiple secondary burials dated at ca. 500 14C years BP. The site is comprised of a minimum number of 77 individuals, represented by both sexes and all age categories. The mortality profile is characterized by a bimodal pattern with a peak of greater representation of individuals younger than 3 years and another comprising the range between 20 and 34.9 years old. These results are discussed in relation to the paleopathological information available for the site, indicating that individuals suffered mainly disruptions in growth and development by systemic stress. The mortality profile obtained suggests that this skeletal series would not have formed as a result of a catastrophic event. On the contrary, it is an atricional mortality profile, consisting of individuals who died at different times and places and for varied reasons. Later, skeletal remains were grouped into secondary bundles and simultaneously buried at the site. Body manipulation and secondary burials are common in the context of a social reorganization that occurred in the area and in neighbouring regions during the Final Late Holocene. Copyright © 2013 John Wiley & Sons, Ltd.