The migration of humans to the New World took place in the late Pleistocene epoch. There are three prevailing theories that describe how the first Americans entered the continents of the Western Hemisphere. One theory describes a route by foot across the Bering Land Bridge while the other two theories describe a maritime voyage closely following the coast. The maritime entry has gained credibility recently with closer examination of the geological and archaeological evidence. Some of these from coastal locations along both coasts of the Americas. One of these sites is located in an unexpected place, Chile. Archaeological data from Monte Verde in South America indicates a presence of humans at 14,600 B.P. This early date, earlier than most North American sites, fuels a hypothesis that the first people to settle Monte Verde came from the west, across the South Pacific Ocean as a possible fourth scenario of how people arrived in the Americas.

This doctoral thesis presents the results of the pioneering archaeological investigation conducted in the Northern Mexican Highlands with the aim to evaluate the existing indicators of the earliest human occupations at the end of the Pleistocene and discover new evidence of ancient cultural manifestations through a systematic exploration of an endorheic basic in the Zacatecas desert, a region never studied before. An exhaustive survey and analysis of the available literature on Mexican prehistory establishes the weak points of the local paradigms, differentiating between academic myths and objective realities. A complete historiography of the topic of the earliest humans in Mexico has been achieved, for the first time. The study of several collections of flaked stone artefacts, in different cities in Mexico, show new indicators of the presence of bearers of the Late Paleoamerican cultures, in regions where their presence had been weakly confirmed. The most important part of the research consisted in fieldwork realised during two long seasons; the first one dedicated to the surface explorations and the second one to excavations. Thirty-five new archaeological sites were discovered in the first phase, most of them open campsites reminiscent of hunter-gatherer societies, with a richness of stone artefacts on their surface. They indicate a long cultural sequence, going from the Late Pleistocene to the Late Holocene and the historic periods. Four sites were further studied by fourteen test excavation units: Dunas de Milpa Grande, San José de las Grutas, the Chiquihuite Cave and Ojo de Agua. Two new archaeological cultures were identified, one at Dunas (an interesting assemblage of limestone and basalt flaked stone tools) and another one at San José (a limestone concave-based points complex). First indicators of ʻolder than Clovisʼ human presence have also been obtained. The palaeoenvironmental data provide a preliminary reconstruction of the Late Pleistocene-Early Holocene landscape of the basin, based on geology, extinct fauna, phytolith and mollusc analyses. Radiocarbon and OSL results support a first cultural and paleoclimatic model for the study area. This investigation also discovered the first case of a “black mat” in Mexico: a black layer of sediment deposited under specific environmental conditions during the Younger Dryas cooling event.

The peopling of the Americas, including the possibility that maritime peoples followed a coastal route from Northeast Asia into the New World, is a topic of major interest in archaeology. Paleocoastal sites on California`s Northern Channel Islands (NCI), dating between ~13,000 and 8000 years ago, may support this coastal migration theory. Until recently, however, we knew little about Paleocoastal technologies, settlement, and lifeways on the islands. Combining traditional archaeological approaches with experimental and archaeometric techniques, I examine Paleocoastal settlement and resource use on San Miguel and Santa Rosa islands. Recently discovered Paleocoastal sites have produced sophisticated chipped stone technologies, with bifacially-flaked points and crescents of extraordinary craftsmanship. Exploring lithic raw material procurement strategies, I demonstrate a Paleocoastal preference for island cherts from sources centered on western Santarosae. Using experimental and archaeometric techniques, I show that Paleocoastal peoples systematically employed heat-treatment to manufacture finely crafted bifaces from island cherts. Using stable oxygen isotope (δ18O) analyses of marine shells from Paleocoastal sites, I examine paleo-sea surface temperatures, seasonality of shellfish collecting, and human sedentism. Evaluating whether such occupations were seasonal or year-round, I tested different sampling strategies for California mussel shells, showing that a method used by many California archaeologists provides erroneous seasonality interpretations for ~35 percent of sampled shells. Using a more intensive sampling strategy, I demonstrate that some Paleocoastal sites were used seasonally, but three substantial middens dating to 8200, 9000, and 10,000 cal BP produced evidence for shell harvesting during all four seasons. This suggests that the NCI were occupied more or less permanently and year-round by at least 10,000 years ago. My research suggests that Paleocoastal peoples had a strong commitment to maritime and island lifeways starting at least 12,000 years ago. From that time until ~8000 years ago, Paleocoastal peoples relied primarily on island resources despite their close proximity to the mainland. The presence of a relatively large, permanent, and distinctive Paleocoastal population on the NCI may also support the coastal migration theory and an even deeper antiquity of human settlement and sedentism on the NCI. This dissertation includes previously published and unpublished co-authored material.

This review considers important themes concerning the peopling of South America that have been analyzed in the various articles in this volume. The identification of the oldest lithic tools, the criteria of human association with extinct faunas and the selection of analytical units used to describe the process of peopling are the main themes. Paleoenvironmental issues and its relevance to understand the process of human colonization are also considered. / Se presenta una discusión acerca de algunos temas centrales relacionados con el poblamiento de América del Sur que han sido objeto de análisis en los distintos artículos de este volumen. Se enfatizan cuestiones de identifi cación de las herramientas líticas más antiguas, criterios de asociación humana con fauna extinta y elección de unidades analíticas utilizadas para describir los procesos de poblamiento. También se considera la relevancia de los aspectos paleoambientales para comprender el proceso de colonización humana.

In this paper we present paleoenvironmental evidence of the Late Pleistocene and Early Holocene in order to understand the process of human settlement in the Puna region of Argentina. We will analyze chronological evidence and the archaeological record of early hunter-gatherer occupations dated between 10,500 to 9000 BP (12,500 to 10,000 cal BP). Finally, we discuss specific cultural and environmental aspects related to the human dispersion and colonization of the altiplano zone. / En este trabajo se presentan las evidencias paleoambientales de finales del Pleistoceno y comienzos del Holoceno con el fin de entenderel proceso de poblamiento humano en la región de la Puna de Argentina. Se analizarán las evidencias relacionadas con lacronología y el registro arqueológico de las ocupaciones tempranas de cazadores-recolectores datadas entre 10.500 AP hasta 9000 AP (12.500-10.000 cal AP). Por último, discutiremos aspectos culturales y ambientales específicos vinculados con la dispersión y colonización humana del espacio altiplánico.

Even though the analysis of DNA from archaeological bone comes with some major limitations, it constitutes the most directmeans of investigating prehistoric population dynamics. The interdisciplinary contextualization of genetic data with the archaeological and palaeoecological record helps to reconstruct past population histories and the demography of ancient populations. For South America, palaeogenetic studies have become increasingly important. Here we review the existing ancient DNA data from pre-Columbian individuals to assess their potential to contribute to our understanding of early South American population history. The spatial and temporal distribution of ancient South American populations analysed to date is very uneven and the data resolution of the analysed genetic markers is low. Nevertheless, the data suggest that there were population dynamic processes accompanying cultural development in Western South America. With the new methodologies and better sampling strategies employed in current paleogenetic projects and more effective interdisciplinary cooperations it will be soon possible to achieve a better understanding of the peopling of the continent and the succeeding population history. / Aún cuando el análisis de ADN de huesos arqueológicos tiene algunas grandes limitaciones, constituye la manera más directa de investigar eventos prehistóricos de dinámica poblacional. La contextualización interdisciplinaria de los datos genéticos con los registros arqueológico y paleoecológico permite reconstruir las historias poblacionales pasadas y la demografía de sociedades antiguas. Por otro lado, el número de estudios paleogenéticos en Sudamérica se está incrementando. En este artículo revisamos los datos de ADN antiguo de individuos prehispánicos que existen en la actualidad con la finalidad de evaluar su potencial para contribuir a nuestro entendimiento de la historia temprana del poblamiento de Sudamérica. La distribución espacial y temporal de las poblaciones sudamericanas antiguas muestreadas a la fecha es muy irregular y la resolución de los marcadores genéticos analizados esbaja. Sin embargo, los datos sugieren que existieron procesos de dinámica poblacional que acompañaron el desarrollo cultural de la parte oeste de Sudamérica. Con las nuevas metodologías y mejores estrategias de muestreo que se emplean hoy en día en los proyectos de paleogenética, y con una cooperación interdisciplinaria más efectiva, pronto será posible lograr un mejor entendimiento del poblamiento del continente, así como de los hechos sucesivos de su historia poblacional.

The Atacama Desert (from Arica to Taltal, 18°-25° S), one of the driest environments on Earth, has been considered an inhospitable habitat and hence a major barrier for the hunter and gatherer groups that migrated to South America at the end of the Pleistocene. Recent paleoecological and geomorphologic data, summarized here, show that during the Pleistocene-Holocene transition (ca. 17,500-9500 cal BP) some sectors of the Atacama were much wetter and had greater bioproductivity than today, factors that increase the possibilities of finding early American sites. Here, we first describe the current environment of the Atacama and compare it to past environmental conditions. Second, we present our results that show archaeological evidence for the human colonization of the hyperarid coast (0-900 masl), the intermediate depression (900-2200 masl), the precordillera (2200-3500 masl) and the altiplano (>3500 masl). Finally we discuss some of the possible migratory routes for the peopling of South America. / El Desierto de Atacama (Arica a Taltal, 18°-25° S), uno de los ambientes más áridos del planeta, ha sido considerado un hábitat inhóspito y, por ende, una barrera importante para los grupos de cazadores- recolectores que migraron a Sudamérica a fines delPleistoceno. Recientes datos paleocológicos y geomorfológicos, resumidos aquí, evidencian que durante la transición Pleistoceno-Holoceno (c. 17.500-9500 cal AP) algunos sectores del Atacama fueron mucho más húmedos y tuvieron mayor bioproductividad que hoy, lo que incrementa las posibilidades de encontrar sitios tempranos. Aquí, en primer lugar, describimos el ambiente actual del Atacama y lo comparamos con sus condiciones ambientales pasadas. En segundo lugar, presentamos las evidencias arqueológicas que dan cuenta de la colonización humana de la costa hiperárida (0-900 metros sobre el nivel del mar), la Depresión Intermedia (900-2200 metros sobre el nivel del mar), la precordillera (2200-3500 metros sobre el nivel del mar) y el altiplano (>3500 metros sobre el nivel del mar). Por último, discutimos algunas de las posibles rutas migratorias para el poblamiento de Sudamérica.

O aprovisionamento ou obtenção das rochas e minerais aptos para lascamento ou polimento constitui um dos temas mais abordados pela arqueologia de caçadores-coletores ao redor do mundo. O aprovisionamento lítico é um fenômeno cultural cujo estudo não está limitado à determinação da proveniência de tais materiais, integrando aspectos geomorfológicos e geológicos como disponibilidade, abundância e localização de afloramentos e clastos, com aspectos humanos da seleção como qualidade para as tarefas requeridas, cor, forma de remoção ou escavação e gestão tecnológica. A presente dissertação aborda o problema do aprovisionamento lítico em Dourado, região de cuestas basálticas no centro do estado de São Paulo, onde se insere o sítio Bastos, que apresenta datas entre ca. 7,650 e 12,640 anos cal a.P. e artefatos líticos manufaturados em arenito silicificado. Tendo como base uma relação conceitual entre tecnologia e suas consequências na paisagem lítica e uma perspectiva geoarqueológica sobre os recursos líticos, é proposto um protocolo de pesquisa que integra: a) prospecção de fontes potenciais e utilizadas de matéria-prima lítica num setor central e sul respeito do sítio; b) análise macroscópica mediante classificação paradigmática das amostras coletadas; c) análise petrográfico microscópico; d) e análise tecnológica dos artefatos recuperados em fontes, ocorrências e sítios. Os resultados indicam: 1) uma paisagem lítica caracterizada por extrações em afloramentos e clastos de arenito silicificado de muito boa a excelente qualidade para lascamento num raio mínimo de aprovisionamento diário de 3 km desde o sítio Bastos; 2) uma tendência a uma maior representação de poucas variedades específicas de arenito silicificado nos níveis antigos (ca. 12,500 cal a.P.) do sítio respeito dos mais tardios (<9000 cal a.P.), o que teria relação com a disponibilidade imediata; 3) uma tecnologia fora das fontes diferenciada entre o reverso das cuestas (setor central) e o frente da mesma (setor sul), com destaque no primeiro caso, do segundo registro de produção de lâminas (lascas alongadas especializadas) no Brasil. Concluiu-se com a ênfase na necessidade de se ampliar as escalas e métodos de análise da presente 5 pesquisa e de se realizar propostas semelhantes em outras partes do país, para um estudo comparativo sistemático do aprovisionamento lítico em diferentes períodos e lugares. / The procurement of rocks and minerals suitable for knapping and grinding constitutes one of the main topics of hunter-gratherer archaeology all around the world. As a cultural phenomenom, from the perspective of its study, lithic procurement is not restricted to sourcing materials, but integrates geomorfological and geological aspects such as availability, abundance and location of outcrops and clasts, with human aspects of lithic selection, such as quality, color, extraction or excavation mode and technological processing. The present Master thesis focuses on the problem of lithic procurement in the Dourado region, in the basaltic cuestas landscape of central São Paulo state, where the Bastos site is located, which exhibits dates between ca. 7,650 and 12,640 cal years BP and lithic artifacts manufactured in silicified sandstone. Using a conceptual approach that relies on the relationship between technology and its consequences in the lithic landscape with a geoarchaeological perspective on lithic resources, the research protocol integrates: a) potential and utilized raw material sources survey in a central and southern sector from the site; b) a paradigmatic macroscopic classification of the samples; c) a petrographic microscopic analysis; d) and technological analysis of artifacts recovered in sources, isolated spots and sites. Results indicate: 1) a lithic landscape characterized by extractions on very good-to-excellent knapping quality silicified sandstone outcrops and clasts in a 3-km minimum foraging radius around the Bastos site; 2) a trend towards a higher representation of few specific silicified sandstone varieties in the older levels (ca. 12,500 cal a.P.) as compared to the later ones (<9000 cal a.P.), which would be the effect of an inmediate availability; 3) an out-of-the-sources technology differentiated between the backside of the cuestas (central sector) and the front (southern sector), with the remarkable finding in the former,of the second record of blade production (specialized long flakes) in Brazil. An emphasis on the need of widening the scale and methods of this research is concluded, together with the need of making similar approaches in other parts of the country that will allow a systematic comparative study of lithic procurement in different periods and places.

This article presents key data and discussion about the initial peopling of northwestern South America, highlighting its strategic significance in the continental context, cultural variability and landscape change over time. In Colombia there is very little relevant information regarding occupations prior to 12,000 BP; in contrast, the information is abundant relative to a number ofearly contexts during the Pleistocene-Holocene transition. The variability among unifacial and bifacial lithic assemblages reported in different physiographic regions indicates alternative models on early settlement to regional level. Considering the importanceof the inter-Andean valley of the Magdalena River, this article emphasizes the archaeological contexts and paleoenvironmental information, highlighting environmental impacts associated not only to global climate change, but in particular of the effects ofvolcanism. The article stresses the findings and chronologies of bifacial lithic assemblages of the Magdalena Valley in relation to the early archaeology of northwestern South America. / En este artículo se presentan los principales datos y reflexiones asociados al poblamiento inicial del noroccidente de Sudamérica debido a su significado estratégico en el marco continental, se destacará la variabilidad cultural y se enfatizarán los cambios depaisajes en el transcurso del tiempo. En Colombia existe muy poca información relevante relacionada con las ocupaciones anterioresa 12.000 AP; en contraste, la información es abundante en cuanto al número de contextos tempranos durante la transición Pleistoceno-Holoceno. La variabilidad entre los conjuntos líticos unifaciales y bifaciales reportados en distintas regiones fisiográficas plantea propuestas de modelos alternativos sobre el poblamiento temprano a escala regional. Considerando la importancia del valle interandino del río Magdalena, se recalcan los contextos arqueológicos e información paleoambiental. Asimismo, se destacan los impactos ambientales que demuestran por qué no perduraron las evidencias del Pleniglacial, lo que podría deberse a efectos asociados no solo al cambio climático global, sino, en particular, a causa del vulcanismo. Este trabajo resalta los hallazgos y cronologías de los conjuntos líticos bifaciales del valle del Magdalena en relación con la arqueología temprana del noroccidente de Sudamérica.

Recent research has revealed human settlement on the Pacific coast of Canada extending back nearly 14,000 years, but much of the late Pleistocene record is unknown due to shifting sea levels, poor understanding of Cordilleran ice extent, and limited research on the biota of the coast during this time. This study, undertaken in Quatsino First Nation and ‘Namgis First Nation territories as part of the Northern Vancouver Island Archaeology and Palaeoecology Project, employs modern multi-proxy analysis of lake sediment cores from two sites on northern Vancouver Island to reconstruct palaeoenvironments during and immediately following the Fraser Glaciation in coastal British Columbia. Evidence from radiocarbon samples, pollen, ancient environmental DNA, plant macrofossils, and diatoms indicates that Topknot Lake on the outer coast of Vancouver Island has remained unglaciated through most of the local Last Glacial Maximum since ca. 18,000 cal BP. A non-arboreal herb-shrub tundra assemblage prevailed from ca. 17,500-16,000 cal BP with taxa including willows (Salix), grasses, sedges (Cyperaceae), heathers (Ericaceae), and sagewort (Artemisia). After ca. 16,000 and into the terminal Pleistocene, Topknot Lake was dominated by pine, alder (Alnus), ferns, and aquatic plant species. In the Nimpkish River Valley deep in the Vancouver Island Ranges, Little Woss Lake also demonstrates a record extending to the late Pleistocene (ca. 14,300 cal BP). The environment comprised dry and cool conifer woodland dominated first by fir (Abies) until ca. 14,000 cal BP, then by pine, alder, and ferns from ca. 14,000-12,000 cal BP. eDNA evidence from ca. 14,000 cal BP corroborates these plant taxa as well as indicating brown bear and Chinook salmon in and around the basin at that time. A mixed-conifer assemblage consisting of pine, western hemlock, and alder followed from ca. 12,000-11,100 cal BP into the early Holocene. Collectively, these indicators demonstrate an open environment on the outer coast of northern Vancouver Island since ca. 18,000-17,500 cal BP and well-established biotic communities across the region throughout the late Pleistocene. These results inform future archaeological research for early human habitation in coastal British Columbia and provide key evidence to support the viability of the coastal migration route for the first peopling of the Americas. / Graduate / 2020-12-11