Michael R Waters

Texas A&M University | TAMU · Center for the Study of the First Americans

Lanceolate projectile points of the Clovis complex and stemmed projectile points of the Western Stemmed Tradition first appeared in North America by ~13 thousand years (ka) ago. The origin, age, and chronological superposition of these stemmed and lanceolate traditions are unclear. At the Debra L. Friedkin site, Texas, below Folsom and Clovis horiz...

North and South America were the last continents to be explored and settled by modern humans at the end of the Pleistocene. Genetic data, derived from contemporary populations and ancient individuals, show that the first Americans originated from Asia and after several population splits moved south of the continental ice sheets that covered Canada...

The cause, or causes, of the Pleistocene megafaunal extinctions have been difficult to establish, in part because poor spatiotemporal resolution in the fossil record hinders alignment of species disappearances with archeological and environmental data. We obtained 172 new radiocarbon dates on megafauna from Rancho La Brea in California spanning 15....

Bone fragments embedded in a rib of a mastodon (Mammut americanum) from the Manis site, Washington, were digitally excavated and refit to reconstruct an object that is thin and broad, has smooth, shaped faces that converge to sharp lateral edges, and has a plano-convex cross section. These characteristics are consistent with the object being a huma...

Fluting is a technological and morphological hallmark of some of the most iconic North American Paleoindian stone points. Through decades of detailed artifact analyses and replication experiments, archaeologists have spent considerable effort reconstructing how flute removals were achieved, and they have explored possible explanations of why flutin...

Hall's Cave, Texas, contains a radiocarbon dated sediment record extending from the Last Glacial Maximum through the Holocene. Changes in the characteristics of the sediments and the pattern of sedimentation in the cave correlate with environmental and climatic shifts over the last 20,000 years. The sediments in Hall's Cave preserve well-documented...

One of the prevailing hypotheses for the origin of the Younger Dryas (YD) cooling event is that it resulted from a bolide impact or airburst. Purported impact markers peak at or near the YD basal boundary layer at Northern Hemisphere locations. In this study, the ¹⁸⁷Os/¹⁸⁸Os ratios and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re) abunda...

A chert object embedded in the cranium of a bison found at the Alexon site, Florida, is cited as direct evidence of human and megafauna interaction at the end of the Pleistocene in the American Southeast. Previous analyses identified the chert object as the mid-section of a lanceolate projectile point. Radiocarbon ages on unpurified bison collagen...

Thirty-two radiocarbon ages on bone, charcoal, and carbonized plant remains from 10 Clovis sites range from 11,110 ± 40 to 10,820 ± 10 14 C years before the present (yr B.P.). These radiocarbon ages provide a maximum calibrated (cal) age range for Clovis of ~13,050 to ~12,750 cal yr B.P. This radiocarbon record suggests that Clovis first appeared a...

The Younger Dryas (YD) abrupt cooling event ca. 12.9 ± 0.1 ka is associated with substantial meltwater input into the North Atlantic Ocean, reversing deglacial warming. One controversial and prevailing hypothesis is that a bolide impact or airburst is responsible for these environmental changes. Here, highly siderophile element (HSE; Os, Ir, Ru, Pt...

Large-scale changes in global climate at the end of the Pleistocene significantly impacted ecosystems across North America. However, the pace and scale of biotic turnover in response to both the Younger Dryas cold period and subsequent Holocene rapid warming have been challenging to assess because of the scarcity of well dated fossil and pollen rec...

In April 2018, the Center for the Study of the First Americans, Hakai Institute, and University of Victoria co-sponsored a five-day workshop investigating the origins of Western Stemmed technologies and their relationship with other Paleoindian and Paleolithic technocomplexes of far western North America, Beringia, and northeast Asia. This Perspect...

The Page-Ladson site, currently buried and submerged in a sinkhole in northwestern Florida, demonstrates evidence of human occupation in North America by 14,550 calendar years ago (cal yr BP). This paper combines new diatom evidence with existing palynological data to strengthen paleoenvironmental interpretations at the site. The Page-Ladson sinkho...

Forty years ago, Knut Fladmark (1979) argued that the Pacific Coast offered a viable alternative to the ice-free corridor model for the initial peopling of the Americas—one of the first to support a “coastal migration theory” that remained marginal for decades. Today, the pre-Clovis occupation at the Monte Verde site is widely accepted, several oth...

Drivers of Late Quaternary megafaunal extinctions are relevant to modern conservation policy in a world of growing human population density, climate change, and faunal decline. Traditional debates tend toward global solutions, blaming either dramatic climate change or dispersals of Homo sapiens to new regions. Inherent limitations to archaeological...

The early archaeological record of Beringia is complicated by the occurrence of several lithic industries. Site assemblages, dating from 14,000 to 12,800 years ago and located from the Yana‐Indigirka Lowlands of Siberia to the upper Tanana River basin, contain artifacts characteristic of the Nenana technological complex. After 12,800 years ago, sit...

Found in 1968, the archaeological site of Anzick, Montana, contains the only known Clovis burial. Here, the partial remains of a male infant, Anzick-1, were found in association with a Clovis assemblage of over 100 lithic and osseous artifacts—all red-stained with ochre. The incomplete, unstained cranium of an unassociated, geologically younger ind...

Genomic studies indicate that the first Pleistocene foragers who entered North America diverged from ancestral populations in Beringia sometime after the Last Glacial Maximum (LGM); however, several archaeological sites in North America have been proposed to predate the LGM. We present the results of our excavation and analysis of one such site, Co...

The Buffalo Ranch site (41BU119) is located along the Brazos River in Burleson County, Texas, under 10 m of late Quaternary alluvium. Here, Wilson and Big Sandy projectile points were found in natural levee sediments. Three calibrated radiocarbon ages place the site between 9424 and 9666 cal yr BP. Buffalo Ranch adds to our understanding of the lat...

Stone tools and mastodon bones occur in an undisturbed geological context at the Page-Ladson site, Florida. Seventy-one radiocarbon ages show that ~14,550 calendar years ago (cal yr B.P.), people butchered or scavenged a mastodon next to a pond in a bedrock sinkhole within the Aucilla River. This occupation surface was buried by ~4 m of sediment du...

How and when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we found that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (ka) and after no more than an 8000-year i...

During the late Paleoindian and early Archaic periods, the Southern Plains witnessed a diversification in unfluted lanceolate point styles. The classification of these points into distinct and meaningful typological groups continues to play a fundamental role in building an understanding of cultural changes at the end of the last Ice Age. In this s...

Fell's Cave lies near the Magellan Straits of South America's Southern Cone. This was the first site to provide evidence of a late Pleistocene occupation of South America, and it is the site where the Fishtail projectile point type was defined. Previous radiocarbon ages from Fell's Cave on charcoal samples from three hearths in the late Pleistocene...

Significance Archaeological discoveries at Wally’s Beach, Canada, provide the only direct evidence of horse and camel hunting in the Americas at the end of the last Ice Age. Here, seven horses and one camel were attacked and butchered near a river crossing by prehistoric hunters. New radiocarbon dates revise the age of these kill and butchering loc...

Roughly thirteen thousand years ago, Clovis hunters cached more than fifty projectile points, preforms, and knives at the toe of a gentle slope near present-day Elgin, Bastrop County, in central Texas. Over the next millennia, deposition buried the cache several meters below the surface. The entombed artifacts lay undisturbed until 2003. A circuito...

The Paleoindian Goshen complex occurs in the northern Plains and eastern Rocky Mountains. Since its identification, there has been much discussion about the chronological placement of the Goshen complex. This is especially true because diagnostic Goshen projectile points occur stratigraphically below Folsom artifacts at two sites, and early dates f...

Clovis, with its distinctive biface, blade and osseous technologies, is the oldest widespread archaeological complex defined in North America, dating from 11,100 to 10,700 (14)C years before present (bp) (13,000 to 12,600 calendar years bp). Nearly 50 years of archaeological research point to the Clovis complex as having developed south of the Nort...

Humans first left Siberia and colonized the Americas perhaps around 16,000 years ago, and the Clovis archaeological complex in North America has traditionally been linked to this migratory pulse. Archaeologists searching for evidence of Clovis technological antecedents have focused their attention on the Beringian and Siberian archaeological record...

Archaeological evidence from North America shows that Clovis complex sites date between 13,000 and 12,600 cal yr BP. The evidence for the Clovis complex pre-dating 13,000 cal yr BP is equivocal. Artifact assemblages are found at a number of sites in South America that date to 13,000 cal yr BP that have no affinity to Clovis. These data show that bo...

As research continues on the earliest migration of modern humans into North and South America, the current state of knowledge about these first Americans is continually evolving. Especially with recent advances in human genomic studies, both of living populations and ancient skeletal remains, new light is being shed in the ongoing quest toward unde...

Archaeological sites within physically “active” soils, such as Vertisols, are considered suspect by archaeologists because of concern for possible disturbance of stratigraphic context. Pedology, micromorphology, and geochemistry are tools useful for assessing soil mixing. Clay‐rich floodplain soils (Typic Haplusterts) were examined at the Debra L....

The evolution of magnetization within a floodplain soil begins with initial deposition of magnetic particles during sedimentation and continues via subsequent alteration and growth of iron-bearing compounds by pedogenic and biologic processes. Measurements of soil magnetic properties capture information about the developmental history of the soil a...

The tip of a projectile point made of mastodon bone is embedded in a rib of a single disarticulated mastodon at the Manis site in the state of Washington. Radiocarbon dating and DNA analysis show that the rib is associated with the other remains and dates to 13,800 years ago. Thus, osseous projectile points, common to the Beringian Upper Paleolithi...

Eolian sediments are common within the middle Gila River Valley, southern Arizona, and reflect variability in eolian and fluvial processes during the late Holocene. This study focuses on deciphering the stratigraphic record of eolian deposition and associated luminescence dating of quartz extracts by single aliquot regeneration (SAR) protocols. Str...

Compelling archaeological evidence of an occupation older than Clovis (~12.8 to 13.1 thousand years ago) in North America is present at only a few sites, and the stone tool assemblages from these sites are small and varied. The Debra L. Friedkin site, Texas, contains an assemblage of 15,528 artifacts that define the Buttermilk Creek Complex, which...

Some 13,000 years ago, humans were drawn repeatedly to a small valley in what is now Central Texas, near the banks of Buttermilk Creek. These early hunter-gatherers camped, collected stone, and shaped it into a variety of tools they needed to hunt game, process food, and subsist in the Texas wilderness. Their toolkit included bifaces, blades, and d...

For many years cultural layer 7 at the Ushki sites, Kamchatka was considered to represent the earliest human occupation of Beringia, because four radiocarbon dates indicated an age of 16,000–17,000 calendar years ago (cal BP). In 2003, however, Goebel et al. reported that layer 7 more likely formed only 13,000 cal BP, nearly 4000 years later than N...

The Topper and Big Pine Tree sites are located along the central Savannah River in South Carolina. Both sites contain significant Clovis horizons and the Topper site is reported to contain a pre-Clovis assemblage characterized by a smashed core and microlithic industry. The stratigraphic position of the early assemblage at Topper is indeed below Cl...

Contemporaneity of people and the American mastodon (Mammut americanum) at Big Bone Lick, Kentucky, has been extensively debated for more than two hundred years. Newly interpreted stratigraphic excavations and direct AMS ,14C measurements on mastodon bones from Big Bone Lick, Kentucky, indicate that the megafauna area palimpsest of fossils spanning...

Impressions in a basaltic tuff located around Valsequillo Reservoir near Puebla, Mexico, have been interpreted as human and animal footprints along an ancient lakeshore, and are cited as evidence of the presence of humans in North America at 40 ka B.P. In this paper, we present new data that challenge this interpretation. Paleomagnetic analyses of...

Direct dating of a Paleoindian bone point from Sheriden Cave, Ohio, yielded a radiocarbon age of 10, 915 ± 30 14C yr B.P. (UCIAMS-38249). This date was derived on highly purified bone collagen. This bone point was found in association with another bone projectile point and a reworked, fluted Clovis projectile point. The artifacts from Sheriden Cave...

Late Quaternary alluvial chronologies are established for five streams (Gila River, Salt River, Tonto Creek, Santa Cruz River, and San Pedro River) in the Gila basin of southern Arizona. Each streams has a complex history of deposition, erosion, and landscape stability that structured and fragmented the archaeological record over the last 15,000 ye...

The skeleton of a human adult female was excavated from alluvial sediments along the Gulf Coastal Plain of Texas. She was buried face down in an extended position with her hands crossed beneath the waist. Initial radiocarbon ages indicated that this skeleton dated to the late Pleistocene. Geoarchaeological and archaeological excavations at the site...

When did humans colonize the Americas? From where did they come and what routes did they take? These questions have gripped scientists for decades, but until recently answers have proven difficult to find. Current genetic evidence implies dispersal from a single Siberian population toward the Bering Land Bridge no earlier than about 30,000 years ag...

Using a modified seismic reflection imaging system with rapid translation of receivers, stratigraphic profiles were collected at the Gault site in central Texas. For rapid data collection, spikeless geophone receivers were placed in sand-filled bags at tight spacing, and these receivers were rapidly pulled along the ground surface between shots. Sh...

The Clovis complex is considered to be the oldest unequivocal evidence of humans in the Americas, dating between 11,500 and 10,900 radiocarbon years before the present (14C yr B.P.). Adjusted 14C dates and a reevaluation of the existing Clovis date record revise the Clovis time range to 11,050 to 10,800 14C yr B.P. In as few as 200 calendar years,...

Americas Redefining the Age of Clovis: Implications for the Peopling of the This copy is for your personal, non-commercial use only. clicking here. colleagues, clients, or customers by , you can order high-quality copies for your If you wish to distribute this article to others here. following the guidelines can be obtained by Permission to republi...

Features interpreted as human footprints ~40 ka old have been reported from the Toluquilla quarry near Valsequillo Reservoir, 15 km south of the city of Puebla in central Mexico (Gonzalez et al., 2006). The indentations were found in an indurated basaltic lapilli tuff informally known as the Xalnene Ash. The ~40 ka age of the tuff was based on opti...

A report of human footprints preserved in 40,000-year-old volcanic ash near Puebla, Mexico (http://www.royalsoc.ac.uk/exhibit.asp?id=3616&tip=1), was the subject of a press conference that stirred international media attention. If the claims (http://www.mexicanfootprints.co.uk) of Gonzalez et al. are valid, prevailing theories about the timing of h...

Archaeological surveys and prehistoric settlement patterns are best interpreted when placed on a geomorphic map that defines the distribution and age of physical landforms. Survey data can thus be used to address questions of archaeological site visibility and synchronic and diachronic site patterning on the Gila River Indian Reservation, Arizona....

Regular unscheduled movements of rancherías within a confined area or settlement district result in the phenomenon described as “village drift,” a process whereby a settlement may change its location gradually by several kilometers over a period of years. This article presents a model of village drift based on data acquired from recent archaeologic...

Connection between floodplain changes and culture changes hard to decipher because: (1) different resolution of records; (2) floodplain changes not necessarily reflected in both stratigraphic and dendroclimatic records; and (3) Salt and Gila floodplains may have somewhat different alluvial histories. Future work needs to: (1) determine how far up t...

The Ushki Paleolithic sites of Kamchatka, Russia, have long been thought to contain information critical to the peopling of the Americas, especially the origins of Clovis. New radiocarbon dates indicate that human occupation of Ushki began only 13,000 calendar years ago-nearly 4000 years later than previously thought. Although biface industries wer...