Abstract:

One of the most controversial and difficult aspects of recognizing very early human occupations in the Western Hemisphere deals with our ability to identify chipped stone artifacts made by humans as opposed to other non-human agents. Homogenous, brittle, fine-grained, or microcrystalline rock is a favorite raw material for stone tool makers and users in all times and places. However, these qualities also make such rocks candidates for natural fracture from taphonomic processes such as wind and water erosion, animal trampling, and frost fracturing. Sophisticated formalized tools are easily recognized. Less formalized tools and debitage become points of contention during investigations into early human occupations. What are the qualities found on lithic debitage and tools that allow investigators to determine if a specimen has been modified by intentional human shaping? This study reviews a series of experiments aimed at identification of macroscopic traits common to human-made lithic artifacts. Results show that commonly surmised traits such as conchoidal fracture initiation on objective piec- es and detached pieces can be the products of natural processes. How- ever, there are a suit of traits such as striking platform configuration, pattern of flake removal scars on dorsal surfaces, distribution and size of flake removals from nodules that reveal uniquely human processes. This study shows that recognition of such traits can be assessed on both individual specimens and on populations of specimens to discrimi- nate between non-human taphonomic processes and human artifact production processes.

Eastern South America, or what is today Brazilian territory, poses interesting problems about the early human occupation of the Amer- icas. Three totally distinct and contemporaneous lithic technologies, dated between 11,000 and 10,000 radiocarbon years BP, are present in different portions of the country: the southern Umbu tradition, with its formal bifacial industry, with well-retouched scrapers and bifacial points; the central-northern Itaparica tradition, totally unifacial, whose only formal artifacts are limaces; and the “Lagoa Santa” industry, completely lacking any formal artifacts, composed mainly of small quartz flakes. Our data suggests that these differences are not related to subsistence or raw-material constraints, but rather to different cultural norms and transmission of strongly divergent chaînes opératoires. Such diversity in material culture, when viewed from a cultural transmission (CT) theory standpoint, seems at odds with a simple Clovis model as the origin of these three cultural traditions given the time elapsed since the first Clovis ages and the expected population structure of the early South American settlers.”

The presence of humans in South America, prior to 12,000 BP, is an ongoing subject of controversy. Independently of the arguments of each researcher, we note at least two analytical biases. For the first, depend- ing on whether the material recovered is on the “good” or “bad” side of the “barrier”, scientific demonstrations do not have the same order of rigor. The second concerns the way in which the archaeological material is studied, limiting that which is presented to a very limited category of artifacts: points. Our more demanding approach combines technological, taphonomic and experimental approaches. We have included the study of the site of Boqueiro de Pedra Furada and two new sites in karstic and sandstone position in the Piaui, for which the arti- facts come from archaeological assemblages dating to more than 17,000 BP. Taking into account the totality of these artifacts demonstrates technological facies that rely on the use of cobble, which we can identify as entirely classical in comparison with those commonly found in all of the countries in Eastern Asia. Alongside this research, a comparative taphonomic analysis has been systematically carried out, which further confirms the presence of technological facies that are not natural. Thus, the increase in discoveries in various geological contexts confirms the existence of human occupations during the Upper Pleistocene in this region of the world.

Clovis technology, as known in the durable record, consists of several distinctive flaked-stone reduction strategies as well as the manufacture of a range of bone, ivory, and antler tools. Stone was flaked to pro- duce large flakes from bifacial cores: blades from two core-reduction technologies, and bifaces for varying purposes including the distinctive points known as Clovis. All these were complex technologies, which demanded expert knowledge and significant skill to achieve, even at a basic level. Special characteristics such as the extraordinary selection of exotic raw materials, production of oversized bifaces for caching, con- trolled full-face and overshot biface flaking, and flat-backed blade core maintenance are some of the features that indicate “deep” technologies that must have had significant and distinguishable antecedents in the archaeological record. These specific technologies span multiple ecolog- ical zones from the sub-arctic to the tropics, indicating an astonishing consistency and a system imposed on environmental factors rather than controlled by them. These features and behaviors are used to propose that Clovis was the product of culture change known as a revitalization movement. This anthropological concept is introduced in detail and then used to suggest that Clovis may not have been a single culture but a disparate set of cultures unified by a technologically coded belief system.

A sample of burnt wood gave a date of 10450 years before Christ. Arose during an archaeological assessment carried out on land of the Reventazon hydroelectric project (PHR) – ICE, between dimensions 265 and 120 m in the forest very humid Tropical with high precipitation and a range of temperatures between 20 ° C – 30° C. Areas of irregular topography that connect small terraces showed cultural remains and presented features suitable for human activities. The water resource 100 metres is the Sibón stream, descends into the Canyon of the Río Reventazón. The island site: The archaeological exploration revealed a panorama of ancient groups activities. Stratigraphically evidence stood: ceramic between 20 – 75cm. A lithic rock with foraminifera set overlaps with the ceramic between 50-80 cm. Another lithic set of silicified shale was revealed between 80 and 160cm identifying slices reafilamiento, slimming, unifaciales and bifacial artifacts (scrapers, scrapers, knives, preform and waste products of size); associated with this was the radio- metric dating. The evidence in these depths indicates interspersed with two stone complexes; of shale never gets to share the space occupied by ceramics, pointing out the result of C14 existed people inhabiting the region at least eight millennia before people who used the ceramic complex located in the first layers. Opens the picture with respect to the first human groups, now needing more in-depth studies to make partnerships with other parts of the continent or otherwise indicate a native tradition in the region.

Ongoing investigations at the Brushy Creek Clovis site (41HU74) in Hunt County, Texas have recovered a total of 78 tools among which are 2 Clovis points, a fluted preform, 9 large curved blades, 10 small (<70 mm) bladelets, and a number of bifaces, end scrapers, and other tools. Recent finds over the last two years have added the broken bit end of a chert adze, a possible burin, a burin spall and an engraved piece of Inoceramus sp. shell. The latter displays an extensive cross-hatched pattern on both faces and is similar to an engraved Incoceramus shell from the Kincaid rock Shelter. Many of the artifacts from the site have the same coloration and UV response as chert from known central Texas Clovis locations such as the Gault site (41BL323). To test the possibility of interaction between the inhabitants of Brushy Creek and central Texas, all of the chert artifacts have been subjected to analysis using X-Ray Fluorescence (XRF), with select artifacts also analyzed by Inductively Coupled Plasma Mass Spectrometry – Laser Ablation or ICP-MS-LA. Both analytical methods confirmed the presence of Gault chert at Brushy Creek. This presentation summarizes the results of the XRF and ICP-MS-LA analysis and discusses the implications for Clovis people interaction and movement across north central Texas.

This paper considers the earliest evidence for people along the coast and on the nearby western Andean slopes of northern Peru from 14000-10000 calibrated years ago. Synthesized and related here are both new and published data generated by three decades of archaeo- logical and paleoecological interdisciplinary research at more than 380 sites that represent the early Huaca Prieta, Fishtail, Paijan and unifacial cultures. The end of this time span was characterized by the appearance of domesticated plants, incipient social differentiation, a semi-sedentary to sedentary lifeway, and population aggregation, all of which formed a palimpsest of ever changing social and economic conditions across many different environments of the study area and set the stage for more complex developments.

At a time when archaeologists are increasingly seeking to define the pre-Clovis horizon (Dziebel 2000; Waters et al. 2011; Gugliotta 2013), the paper revisits early-to-mid 20th century ideas about human origins in the Americas (Florentino Ameghino) and back migrations from the Americas to the Old World across the Bering Strait (e.g., Franz Boas). Although these speculations have long receded to the fringes of science, the rapid accumulation of paleobiological, genetic, linguistic and eth- nological data pertaining to the origins of modern humans in the past 20 years (see Dziebel 2007) asks for the reassessment of the role of the Americas not only as a recipient of modern human populations but also as a source of admixture in the Old World. The discovery of very low genetic diversity among Denisovans – the phenomenon only observed among Amerindians, among living human populations – casts the new light on Pleistocene demographies in Siberia. Mitochondrial DNA fur- nished evidence for the presence of some Amerindian markers (hgs A2, C1) in Siberia and Northern Europe (Der Sarkissian 2011). Autosomal DNA studies (Patterson et al. 2012) have identified “Amerindian admix- ture” in Western European populations. Americanoid skulls have ap- parently survived in South Siberia and Central Asia into the Bronze Age (Okunev, Sopka, Chandman/Xiongnu) (Kozintsev et al. 1999; Schurr & Pipes 2011). Coupled with unusually high levels of linguistic diversity in the Americas (Campbell 1997) and some of the most conservative patterns of linguistic structure (Nichols 1992) and kinship organization (Dziebel 2007), this new multidisciplinary data suggests that archaeo- logical research in the Americas and beyond can benefit from a more complex population exchange and isolation model connecting human populations on both sides of the Bering Strait throughout the Late Pleistocene and the early Holocene.

The Southern Cone exhibits a variety of early contexts with unique features, including isolated sites, such as Monte Verde, or groups of related sites, as the Puna contexts. Yet, the single feature with most widespread geographical distribution is the Fishtail or Fell 1 projectile point. It is found in a variety of contexts and environments throughout South America; specifically in the Southern Cone, in Uruguay, Chile and Argentina. Its typical design and technical traits, such as fluting, are shared in different regions and have been used in proposals about exchange, social identity and migration routes. This presentation will update information and focus on two localities with concentrations of Fishtail points, one in the pampas and the other in Patagonia. Localities Cerro El Sombrero and Los Dos Amigos exhibit similar features regard- ing objects and landscapes. Both hilltops were chosen to discard broken Fishtail points as well as other artifacts, including discoidal stones and small spheres. Based on the assumption that past selections of objects and landscape, were socially significant, we propose that people living in both regions in the Southern Cone during the Pleistocene/Holocene transition were sharing meanings and had more in common than tech- nical knowledge and designs.

The Powar’s II Paleoindian Red Ochre Quarry produced all Paleoindian projectile point types found at the nearby Hell Gap site 48G0305 plus at least five Clovis points. Recent {2013) analysis of materials recovered by the University of Wyoming in 1986 revealed blade cores and blades. The latter were ap rently used to loosen the red ochre in the procurement process and provide evidence of aspecialized Clovis tool kit.

We present here the integration of 16 years of excavation and dating in some of the most important Paleoindian sites from the Basin of Mexico. All the radiocarbon dates quoted here are uncalibrated. The sites in- clude: the Santa Isabel Iztapan Mammoths I and II with lithics associat- ed with mammoth kill sites; the Tocuila mammoths associated with la- har deposits (volcanic mudflows); and the Peñon Woman III, the oldest directly radiocarbon dated human with an age of 10,755 ± 75 years BP. Our results indicate that there are 3 main volcanic ash (tephra) markers during the Late Pleistocene—Early Holocene: 1) the Great Basaltic Ash (GBA) with dates of 28,600 years BP; 2) the Pumice with Andesite (PWA) with an age of 14,600 years BP; and the Upper Toluca Pumice (UTP) with an age of 10,500 years BP. From our stratigraphy we can conclude that the Santa Isabel Iztapan mammoths kill sites are just be- low the Pumice with Andesite (PWA) tephra marker, with radiocarbon dates of 14,600 years BP. The lithics associated are intriguing because they include Lerma points, Scottsbluff points and obsidian prismatic blades. So far no Clovis Points have been found in the Basin of Mexico. Several Paleoindian sites are associated with the cold climatic interval known as Younger Dryas with dates between 10,900 to 9,800 years BP. In the Tocuila mammoths site we also find evidence for the meteorite impact layer reported for the SW of the USA, Canada, Europe, Syria, etc. In Tocuila we find a layer of 10 cm with large amounts of charcoal, magnetic spherules, and melted quartz, with a date of 10,800 ± 50 years BP, but not in association with a black mat deposit.

The Topper site (38AL23) is a multicomponent prehistoric site located on the Savannah River in western Allendale County, South Carolina. A quality chert source is present at the eroding escarpment and in the present river bed. Annual excavations for the past 15 years have revealed an extensive Clovis, Archaic and Woodland record spanning the past 13,000 years. The site has received intensive geological study resulting in a basic chrono-stratigraphic framework spanning at least the past 50,000 years. Artifacts are found on the upland hillside, the es- carpment chert quarry, and on the terrace bordering the river. On the terrace, Clovis artifacts are found buried in colluvial sands OSL dated to about 13,000 years. OSL dates on colluvium below Clovis date from 14 to 15,000 years. Below the colluvium lies a Pleistocene age alluvial terrace with two distinct depositional units each bearing lithic artifacts. Non Clovis type flaked stone artifacts are thought to be in both units created by bipolar reduction. The assemblage consists of cores and choppers and flake tools formed by unifacial retouch and by bend breaking. Some prismatic blades are also present. Radiocarbon dates indicate the lower unit is at least 20,000 years old and as much as 50,000 years or more. Presently, Topper is unique in the western hemisphere for its technology and dating.

Colonization of the Americas was a complex process. Both place of origin and timing of this event are hotly debated. Based on genetics, ge- ography, language, and cultural similarities, most researchers consider Siberia the homeland of the first Americans with migration via the Ber- ing Land Bridge. Others, however, argue earliest colonizers originated in Western Europe, arriving via a trans-oceanic voyage. Some hold that this early colonization event took place before the Last Glacial Maxi- mum (LGM), while others contend it happened much more recently during the Late Glacial. In this paper, I address the peopling of the Americas from a Siberian perspective, using archaeological and ancient DNA data. The Siberian record indicates there were two pulses of modern humans into far northeast Asia during the late Pleistocene, one before and one after the LGM. The colonization of Siberia by modern humans was an episodic process, taking over 10,000 years, setting the stage for the initial peopling of the Americas.

This presentation is a summary of the evidence about Clovis-era subsistence and the different interpretations found in the literature. Sites with adequate evidence about subsistence and diet are scattered in North America over thousands of kilometers, and cannot possibly be fair indications of a pan-continental Clovis-era “diet.” Yet they do suggest large- prey preference. At least 15 sites in the United States and northern Mexico contain fluted points associated with either mam- moth, mastodont, or gomphothere bones. Several more sites appear to contain proboscideans that may have been killed/scavenged/butchered by Clovis-era people, although they lack lithics. The total number of individual proboscideans at these sites is around 60. By comparison, nearly the same number of sites contain Clovis-era features or lithics and associated bones of six large mammal taxa (horse, camel, bison, caribou, bear, deer) , representing fewer individual animals (n=46). Another 10 sites may contain utilized remains of 47 small mammals, mostly rodents and rabbits. If Clovis-era people were preferentially se- lecting the largest animals to kill, and deliberately overlooking smaller species, their choices were rational.

A mid-Wisconsin peopling of North America was first proposed by Muller-Beck in the mid-1960s and was later supported by archae- ological research in the Yukon that has provided evidence of a mid Wisconsin percussion technology consisting of impacted and flaked bones. We develop the “Mammoth Steppe Hypothesis” using Guthrie’s ecological model that identifies a Mammoth Steppe biome present from northern Europe across northern Siberia into Beringia. Recent research in northern Siberia at the Yana Site indicates humans were adapted to the Mammoth Steppe by 27,000 rcybp. We test the Mammoth Steppe Hypothesis using data from several mammoth sites on the North American Great Plains dating between 11,700 and 33,000 rcybp and from experimental breakage of modern elephant limb bone. Evidence supporting the presence of humans consists of impact notches and flaking on mammoth limb bone, the selective breakage of limb bones and the distribution of bone debitage. Because Canada was completely covered with Last Glacial Maximum ice from ca. 22,000 to 11,500 rcy- pb, it is hypothesized that humans entered the Great Plains before the Last Glacial Maximum by a route south from Beringia and east of the Rocky Mountains sometime between 22,000 and 40,000 rcybp during Oxygen Isotope Stage 3.

The presence of human groups in the Americas by the end of the Pleistocene has been demonstrated in numerous archaeological sites in North, Meso and South America. However, the number of early sites associated with human remains is very limited, and to date it is difficult to discuss the processes of the continent’s initial occupation in terms of the biological characteristics of early Americans. The Lagoa Santa region, in Central Brazil is a unique region in the Americas, because it presents dozens of early sites, some of which support the evidence for the human presence in the continent by 12 kyr BP. Since its initial excavation, during 19th century, the Lagoa Santa caves and rockshelters generated over two hundred burials that date between 11.0 and 7.0 kyr BP. Here, we present a review of the biological affinities between these groups, as well as their cultural and archaeological context, resulting from our long term project in the region during the past decade. Using multivariate analysis to compare their cranial morphological affinities with other worldwide groups, we demonstrate that the Lagoa Santa remains share the same morphological pattern seen in other early populations in the Americas and other regions of the planet, a pattern that is significantly distinct from the typical morphology observed among Late Holocene Native Americans. We also explore the notion that these populations, despite being strict hunter-gatherers, showed remarkable cultural diversity, especially when burial practices are considered. In conclusion, the biological and cultural contextualization of the Lagoa Santa early human presence sheds light on important aspects of the origin and adaptation of New World populations at the end of the Pleistocene and early Holocene.

Excavations in the Sarapiquí piedmont yielded evidence of a flake industry associated with tephras dating 6.0 ky BP and older. Artifacts were also recovered at the Gavilan site in the northern lowlands, 6 km from the piedmont sites. Strata in Gavilan attests of a long history of erosional processes including a large scale avalanche (lahar) of Late Pleistocene age, thick flood silt deposits, terrace building by alluvial transport of rocks, and the development of soils. Associated with these were well defined cultural deposits: Level 1 containing ceramics; Level 2 with a lithic assemblage named Toro II of preceramic age; Level 3 of silt sediments with scarce lithics identified as late Paleoindian, related to the bifacial fishtail point tradition; Level 4 with a flake lithic industry, Toro I, the oldest in the relative chronology. At the base, a polimictic lahar is found, regionally recognized by its yellow clayish mud matrix. Lithic artifacts, morphologically and technologically related to those of Level 3, date 12.2 ky BP at La Isla site in the Reventazón region. Deeper strata in La Isla contains Toro I materials, suggesting an older age for this assemblage. Thus far, Toro lithics have been found in similar tropi- cal ecozones in Sarapiquí, Reventazón and Chirripó.

Ancient human copolites (dried feces) directly radiocarbon dated to 14,500 years ago have been recovered from Pleistocene aged deposits containing artifacts and extinct megafaunal remains in the Paisley 5 Mile Point Caves in south central Oregon. Their human origins verified by the extraction of ancient DNA, these are currently the oldest directly dated human remains in the Western Hemisphere. This paper provides an update on the progress of multidisciplinary scientific investigations of this unique site and the many kinds of perishable and nonperishable items preserved there. The evidence indicates the first site occupants were broad-range hunter-gathers well adapted to the Northern Great Basin’s high desert environment of the late Pleistocene.

The abrupt onset of the Younger Dryas cooling episode at ~12.9 ka was marked by a complex array of rapid and potentially linked changes in the Earth’s environmental and biotic systems. Especially intriguing is the close and collective association of North American continental-scale ecological reorganization, megafaunal extinctions, and human adaptive and population shifts. Various hypotheses have been proposed to account for these changes, including the Younger Dryas Boundary (YDB) Cosmic Impact Hypothesis. Our contribution will review the status of this hypothesis, summarizing evidence consistent with atmospheric impact (aerial bursts) including the character, geochemistry, and distribution of nanodiamonds and extreme high-temperature products: impact spherules, melt-glass objects, microtektites; and other proxies. We will also review evidence consistent with the YDB hypoth- esis, including widespread biomass burning at the YDB (e.g. peaks in charcoal and aciniform soot), hydrographic reorganization, extinctions, biotic adaptations and human cultural change.

Scattered sporadically across much of the American West are tight clusters of Clovis artifacts identified as prehistoric caches. Clovis caches consist of bifaces, projectile points, blades, flakes, cores, bone and ivory rods, and occasionally other items that appear to have been carefully set aside rather than used and discarded. Caches potentially provide snapshots of working Clovis tool kits rather than discarded and broken items from kill or camp sites. Further, they provide clues to the logistical problems encountered by highly mobile Ice Age peoples, and reflect the strategies for solving them. As the defining attributes of Clovis caches become clearer, caches are recognized and reported with increasing frequency, in the form of new discoveries in the field and among existing collections. This paper provides an overview of currently known Clovis caches, ranging from assemblages discovered as much as 50 years ago to less familiar collections just coming to light, and examines variation in their contents and context. Their geographic distributions, along with geologic origins of the lithic raw materials they contain, provide clues to the roles they played in prehistoric stone tool and subsistence economies and to their role in the process of colonizing the North American continent.

Enthusiasm for considering a coastal route of human entry into the Americas during the late Pleistocene has grown during the past few decades, and this has only accelerated by recent reports on early Bison and Mastodon kill/butchery sites in coastal Washington State. Nonetheless, relatively little sustained effort has been directed toward finding and exploring the potential archaeological content of extant Pleistocene-aged terrestrial landscape deposits in submerged contexts. Given the logistical challenges involved in exploring submerged landscapes for early sites, the discovery of late Pleistocene sites on the Pacific outer continental shelf is expected to be technically difficult and expensive. Therefore, we will outline the necessary, careful modeling of environment and cultural behavior within the context of dynamic late Pleistocene marine environments. By reviewing the geoarchaeological context of early submerged and intertidal sites, and recent efforts to reconstruct coastal paleolandscapes and paleoecology along western North America’s Pacific coast, we offer a status report on current knowledge and insights into productive directions for future research.

Over the past decade the search for Pre-Clovis sites in North America have involved determining where soils and sedimentary deposits dating to the terminal Pleistocene occur in landscapes. From an archaeological perspective, it is reasonable to assume that sites predating Clovis will be found only where deposits and associated soils old enough to contain them are preserved. A corollary is that where thick deposits post-dating ca. 13 ka are present, evidence of those sites will not be found on the modern land surface. In this paper, I describe a systematic study of late-Quaternary landscape evolution in the Central Plains that documented deeply buried paleosols representing Pre-Clovis-age landscapes. This information is being used to target landform sediment assemblages with high potential for stratified Pre-Clovis cultural deposits. The Coffey site in northeastern Kansas will be presented as a case study. At Coffey, an archaeological component is associated with a bur- ied paleosol developed in the Severance Formation, a lithostatigraphic unit that aggraded between ca. 38 and 18 ka. The geoarchaeological approach presented in this paper has great potential for detecting the elusive Pre-Clovis record of the Central Plains and elsewhere.

The infant from the Anzick site near Wilsall, Montana, associated with 115 Clovis lithic and osseous artifacts, is still the only human skeleton attributable to the Clovis culture. As reported at this conference, the skeleton has provided invaluable genetic data for establishing the ancestry of Native Americans. However, the exact date of the burial deposition has been difficult to ascertain. Each of two antler (probably elk) “foreshafts” provided a precise radiocarbon date of ca. 11,040 rcbp (Beta-163832 and Beta-168967), but a date for the child’s rib is 10,780+-40 rcbp (Beta-163833). Tom Stafford has run multiple assays on filtered collagen and separated amino acids from the child, obtaining ages ranging from 10,240+-120 (AA-2978) to 10,940+-90 (AA-2981), with a rejected outlier of 11,550+-60 rcbp. He thinks the most accurate date is 10,705+-35 rcbp (CAMS-80538). The disparity between ages of the artifacts and the child has raised the suspicion that the artifacts might be centuries-old heirlooms, or that the child’s burial was a later intrusion into the artifact cache. We review eyewitness accounts of the accidental discovery of the deposit to show conclusively that the child lay below the artifact concentration and was not intrusive. The body and the artifacts were deposited in a single ceremonial event and the ostensible age disparity requires some other explanation.

Prior to the late 1990s, the commonly held belief was that Early Paleoindian occupations could not possibly exist in Northeastern Minnesota because of the presence of glacial ice. Even though a single Gainey point had been found in the Cloquet River drainage, it was rationalized away as a curated point from elsewhere. Subsequent research in the region has documented an in situ Folsom site, at least two Gainey points, possible Clovis style blade technology at two separate locations, and reclassified a point initially identified as Holcombe-like to Gainey. Everything except one of the blade locations occurs within an ice-free area that extends from east central Minnesota northeast toward Cana- da. This ice-free area is located along the northern edge of the Superior Lobe and south of the Rainy Lobe’s Vermilion Moraine. The Cloquet River flows through much of this ice-free area, providing a potential transportation route from the dense concentration of Early Paleoindian localities documented near Pine City, Minnesota. Since three of the five points and all the blades are of materials that are locally available, sustained occupation of Northeastern Minnesota in Early Paleoindian times is suggested as opposed to a southern origin for the points.

We have proposed a three-stage colonization model for the Americas that integrates genetic data with existing archaeological, geological, and paleoecological data. Our results support a recent, rapid expansion into the Americas ~16kya that was preceded by a long period of population stability and genetic diversification in greater Beringia and occurred after divergence from an ancestral Asian population ~ 40kya. Two areas of discussion have recently emerged with respect to the genetic data. 1) How does choice of a mitochondrial substitution rate influence estimates for an entry date to the Americas and occupation time of Beringia, and which rate is correct? In general, ‘fast’ substitution rates support a post-LGM entry to the Americas and a shorter occupation of Beringia compared to ‘slow’ substitution rates. 2) What is the relationship of founder population size and subsequent levels of migration between Asia and the Americas, and what is the correct balance between the two? In general, large founder population/low rates of migration and small founder population/high rates of migration are comparable in terms of the resultant Native American genetic diversity. Our results, in combination with constraints provided by archaeological, geological and climatological data, support a ‘fast’ substitution rate and large founder population/low rate of migration.

This overview will highlight what the bones reveal about Paleoamericans from the western half of the United States. Complete and partial skeletons of approximately 30 individuals dated 8000 RC yr. BP and older have been examined including the Spirit Cave Mummy from Nevada, the Horn Shelter No.2 burials from Texas, San Miguel Man from California, and Kennewick Man from Washington. Detailed information on preservation and taphonomy, demography, bone and dental pathology, and cranial and postcranial measurements have been compiled and analyzed to document the occurrence of traumatic injuries, infections, arthritic conditions, oral health, diet, activity patterns and behavior, and population origins and relationships. Although the sample is limited and derived from diverse localities, it provides a foundation for reflecting upon the lives of ancient Americans.

For years, the initial stage of human habitation within Western Beringia was supposed to be not older than the Late Upper Paleolithic,with firm dates younger than the LGM. Discovery of Yana RHS doubled length of the record of human habitation in NE Asia. Human occupations at Yana site pre-date the LGM and show that the area was inhabited almost 30,000 14C years ago. This is the earliest evidence known in the Arctic. The site yielded a unique evidence for Early Upper Paleolithic culture of this remote part of the world. Fauna remains that come from the site belong to almost all species of the local Late Pleistocene habitat. Reindeer, bison, and horse are most numerous. Three major contexts compose the Yana archaeological complex. Two of them are lithic contexts called correspondingly “macro tools” (cores, scrapers, large tools) and “micro tools” (small scrapers, chisel-like pieces, backed blades but almost no burins). The third one is presented by well developed bone/ivory industry that includes hunting equipment, sewing tool kit, and other implements. Numerous personal ornaments and decorated artifacts demonstrate highly developed complicated symbolic behavior. This article presents the data on geology, radiocarbon dating and artifact collection of the Yana site.

Macrophysical climate modeling creates monthly and annual temperature and precipitation charts using century averages for point locations on the landscape. Compilation of these data may be overlain on landscape maps, resulting in display of environmental parameters that would have affected distribution of vegetation and game, and hence people, on the landscape. Vacillation between extremes, which can be seen in the temperature models for this period, suggests the potential for animal population isolation in remote environmental areas. Creating an index of temperature difference identifies time periods likely to have been most risky and provides a tool for examining hypotheses. Changes in seasonal distribution of precipitation also have the potential to dramatically alter vegetation communities, thus introducing new variables in herd distribution and human decision-making. Model output can be viewed either as “still” images or aggregated onto landscape maps and viewed at 1 second per century, creating the illusion of animation and producing a valuable tool for examining potential animal and human movement across the landscape.

Between 12,000 and 8,000 yrs BP, South America Eastern Lowlands was occupied by a stable and diversified hunter-gatherers population. The predominance of generalist subsistence strategies and the lithic industries regional variability show the limits of classic models for the settlement of America to explain the processes of early colonization of this region. In chronological terms, such diversity involves adaptive strategies referring to initial occupations earlier than those assumed by traditional models. Radiocarbon dating that support this hypothesis were obtained for several archaeological sites in Brazil, but the validity of these data has been questioned, as they concern to isolated contexts with discrete characteristics. Also, by analyzing the geographical distribution of the Brazilian archaeological data for Pleistocene-Holocene transition it can be suggest migration flows with differentiated routes, speeds and shift behaviors. Brazilian archeological and paleoenvironmental research suggests that the process of initial colonization of the South American Lowlands entailed multiple strategies, including the valleys of large rivers as inland routes. This dynamic of space usage can promote a rapid displacement over long distances, which, in some cases, explains the existence of almost contemporary sets of sites with similar lithic industries and cultural patterns separate by great distances. For Pleistocene-Holocene transition at least two distinct colonization events would have contributed to the original settlement of the eastern portion of South America that actually corresponds to Brazilian territory. A first set of evidences, among 12,000 and 11,000 14C yrs BP, refers to the colonization of the tropical forests and savannahs in northern, central and northeastern Brazil, whose river systems supposedly served as access routes to the continent interior. Interacting with these tropical landscape mosaics, the Itaparica Tradition and Lagoa Santa Complex hunter-gatherers invested in generalist strategies, based on mobility systems supported by vast territories which boundaries were marketed by rock art regional styles. After 11,000 14C yrs BP a second population movement is related to the colonization of South and Southeastern Brazil and is associated to Umbu Tradition. The more moderate climate, without severe seasonal alternation, associated with the expansion of the Atlantic Forest biome in Southern Brazil, contributed to the first attraction of these populations which develop generalist strategies of forest resource exploitation. Its origin probably has a cultural connection to the pioneer populations who colonized the continent’s southernmost points, expanding northwards and towards the Atlantic coast, until reaching the transition zone between Atlantic Forest and tropical savannahs. According to this data, the colonization of the current Brazilian territory would be at least contemporary to the Clovis horizon, showing, however, quite distinct cultural characteristics, emphatically indicating the existence of continental peopling processes earlier and differentiated than the ones accepted by the classic models.

Archaeologists have long looked to Alaska for evidence of the origins of the first Americans, but still no clear Clovis ancestor has been uncovered there. In this presentation we review the bifacial-rich traditions of north and northwest Alaska, focusing on new results from two fluted-point sites—Serpentine Hot Springs and Raven Bluff, and reviewing earlier work conducted at the Mesa, Sluiceway-Tuluaq, and Nogahabara sites, all thought to potentially date to the terminal Pleistocene. In terms of technology, subsistence, and settlement, these complexes seemingly represent “Paleoindians” in the Arctic; however, none of them (with the possible exception of Sluiceway-Tuluaq) are as old as or older than Clovis. More likely they are the product of a northward spread of Paleoindian people—or Paleoindian technology—into the Arctic at the very end of the Pleistocene, 13,000-12,000 calendar years ago, simultaneous to the dispersal of temperate North American bison into the north.

The demise of the Pleistocene megafauna has become a topic of such longstanding and contentious debate that it is difficult to evaluate the merit of causal evidence independent of entrenched argumentative positions. Generally structured around the role humans and climate did or did not play in the extinction event, the generation of new data, which will ultimately contribute to resolution of the issue, also currently serves to perpetuate particular points of dispute. While I have participated in this debate and have advocated for the role of human hunting, I review the current evidence in light of its implications for what is known about the extinction event (i.e., that it was a rapid, widespread event with an inordinate impact on large-bodied fauna during the Late Pleistocene) and its congruence with plausible expectations of the empirical record. Widespread acceptance of any particular cause, be it human, climate, catastrophe, or disease triggered must be consistent with what the archaeological, paleontological, and paleoenvironmental records can provide? not necessarily with what proponents of either side of the debate claim as essential requirements for resolution.

Most of our knowledge on the peopling of the Americas comes from classical studies of the archaeological record and modern genetics. Ancient genetic studies represent another and largely unexplored means by which crucial new information can be obtained. However the field of ancient DNA is hammered with pitfalls. In this talk I discuss what DNA studies may and may not be able to tell us about the early human colonization of the New World.

Laboratory analyses of samples collected during the 2011-2012 excavations at Rimrock Draw Rockshelter indicate regional eolian and pyroclastic surge materials are collected in “traps” influenced by both mechanical and chemical weathering processes. These tephra accumulations range in size from microstratigraphic layers visible only through particle size and geochemical analysis to massive bar deposits of Mazama ash in the stream channel adjacent to the rockshelter. Thus far, identified ash samples include Newberry (1000 RCYBP), Mazama O (6850 RCYBP), and St Helens SG (13,000 RCYBP), the latter collected from buried deposits above fragments of camelid teeth and a chalcedony flake tool. Trenching of both fluvial and eolian deposits is planned for 2013 to explore the relationship of erosion and deposition processes to the cultural deposits within the rockshelter, and to extract additional tephras toward a more refined tephrachronology of the region. Ash mantled clays within the rockshelter preserve diagnostic artifacts associated with the Western Stemmed tradition; plus overshot flakes, bifaces with overshots, gravers, and fluting flakes that may be associated with fluted point technology. This paper will report the results of tephra analysis on samples collected from both archaeological and geologic deposits, and their relationship to diagnostic projectile points, extinct animal species, and radiocarbon dated features.