Clovis culture is a prehistoric Paleoamerican archaeological culture, named for distinct stone and bone tools found in close association with Pleistocene fauna, particularly two Columbian mammoths, at Blackwater Locality No. 1 near Clovis, New Mexico, in 1936 and 1937, though Paleoindian artifacts had been found at the site since the 1920s. It existed from roughly 11,500 to 10,800 BCE (≈13,500-12,800 years Before Present) near the end of the Last Glacial Period.

Clovis
Map showing the extent of the Clovis culture
Geographical rangeNorth America
PeriodLithic
Datesc. 11,500 – 10,800 BCE[1][2]
Type siteBlackwater Draw
Preceded byPaleo-Indians
Followed byFolsom tradition
"A Clovis blade with medium to large lanceolate spear-knife points. Side is parallel to convex and exhibit careful pressure flaking along the blade edge. The broadest area is near the midsection or toward the base. The base is distinctly concave with a characteristic flute or channel flake removed from one or, more commonly, both surfaces of the blade. The lower edges of the blade and base is ground to dull edges for hafting. Clovis points also tend to be thicker than the typically thin later stage Folsom points. Length: 4–20 cm/1.5–8 in. Width: 2.5–5 cm/1–2
A Clovis point created using bifacial percussion flaking, (which flakes both edges with a percussor). The deep flake initiated from the base constitutes the "flute" characteristic of Clovis and some other early Paleoindian points.

Clovis culture is characterized by the manufacture of "Clovis points" and distinctive bone and ivory tools, and it is represented by hundreds of sites, from which over 10,000 Clovis points have been recovered.[3] Knowledge of the Clovis culture has primarily been gathered from North America.[4] In South America, the similar related Fishtail or Fell projectile point style was contemporaneous to the usage of Clovis points in North America,[5][6] and possibly developed from Clovis points.[7]

The only human burial that has been directly associated with tools from the Clovis culture included the remains of an infant boy found in Montana that researchers named Anzick-1.[8][9][10] Paleogenetic analyses of Anzick-1's ancient nuclear, mitochondrial, and Y-chromosome DNA[11] reveal that Anzick-1 is closely related to some modern Native American populations, including those in Southern North America, Central America, and South America and populations in Central Asia and Siberia, which lends support to the Beringia or coastal Pacific hypotheses that they were responsible for the initial settlement of the Americas.[12][10]

The Clovis culture is traditionally considered to have been based on highly mobile hunter-gatherer populations that heavily engaged in big game hunting, though some recent scholarship has questioned how reliant Clovis hunters were on big game.[13] Some recent experimental research casts doubt on whether Clovis points were well-suited for hunting mammoth at all, and suggests they were more often used as knives;[14][15] however, a counterargument supports the traditional interpretation of points as effective hunting weapons used on large game, including mammoth and other proboscideans.[16]

The Clovis culture was replaced by several more localized regional societies from the Younger Dryas cold-climate period onward. Post-Clovis cultures include the Folsom tradition, Gainey, Suwannee, Simpson, Plainview-Goshen, Cumberland, and Redstone. Each of these is thought to derive directly from Clovis, in some cases apparently differing only in the length of the fluting on their projectile points. Although this is generally held to be the result of normal cultural change through time,[17] numerous other reasons have been suggested as driving forces to explain changes in the archaeological record, such as the Younger Dryas postglacial climate change, and the decline and extinction of North American megafauna as part of the Quaternary extinction event.[18][19] The potential causal role of Clovis hunters in the extinction of the megafauna has been the subject of controversy.[20]

After the discovery of several Clovis sites in western North America in the 1930s (such as Blackwater Draw, NM and Dent, CO), the Clovis people came to be regarded as the first human inhabitants who created a widespread culture in the Americas and the ancestors of most of the indigenous peoples of the Americas.[21][22][23]

Several archaeological discoveries have cast significant doubt on the Clovis-first theory, including sites discovered in present-day Cactus Hill near Richmond, Virginia, Paisley Caves in Paisley, Oregon, the Topper site in Allendale County, South Carolina, Meadowcroft Rockshelter in Jefferson Township, Pennsylvania, the Buttermilk Creek complex site[24] near Salado, Texas, Cueva Fell and Monte Verde in Chile, and the White Sands[25] site near Alamogordo, New Mexico.[26]

The oldest claimed human archaeological site in the Americas is the Pedra Furada hearths in Brazil, controversially dated to 19,000 to 30,000 years before the earliest Clovis sites.[27][28][29]

Description edit

 
Clovis points from the Rummells-Maske Cache Site in present-day Iowa

A hallmark of the toolkit associated with the Clovis culture is the distinctively shaped, fluted-stone spear point known as the Clovis point. The Clovis point is bifacial and typically fluted on both sides. Clovis tools were produced during a roughly 300-year period.[30] Archaeologists do not agree on whether the widespread presence of these artifacts indicates the proliferation of a single people or the adoption of a superior technology by diverse population groups.[31]

The culture is named after artifacts found between 1932 and 1936 at Blackwater Locality No. 1, an archaeological site between the towns of Clovis and Portales, New Mexico. These finds were deemed especially important due to their direct association with mammoth species and the extinct Bison antiquus. The in situ finds of 1936 and 1937 included four stone Clovis points, two long bone points with impact damage, stone blades, a portion of a Clovis blade core, and several cutting tools made on stone flakes.[31] Clovis sites have since been identified throughout much of the contiguous United States, as well as in Mexico and parts of Central America, and even into northern South America.[32]

Clovis people are generally accepted to have hunted mammoths, as well as extinct bison, mastodon, gomphotheres, ground sloths, tapir, Camelops, horse, and other smaller animals. More than 125 species of plants and animals are known to have been used by Clovis people in the portion of the Western Hemisphere they inhabited.[33][34]

The oldest Clovis site in North America has been suggested to be El Fin del Mundo in northwestern Sonora, Mexico, discovered during a 2007 survey.[35] At the site, remains of the gomphothere (elephant relative) Cuvieronius were found associated with Clovis points. In a 2013 study it was estimated to date to 13,390 years Before Present (BP).[35] However, other authors have contested these dates, suggesting the site is likely younger than this, with a 2020 study finding that all reliably datable Clovis sites span from around 13,050 to 12,750 years BP.[5]

Disappearance of Clovis edit

The most commonly held perspective on the end of the Clovis culture is that a decline in the availability of megafauna, combined with an overall increase in a less mobile population, led to local differentiation of lithic and cultural traditions across the Americas.[17][36] After this time, Clovis-style fluted points were replaced by other fluted-point traditions (such as the Folsom culture) with an essentially uninterrupted sequence across North and Central America. An effectively continuous cultural adaptation proceeds from the Clovis period through the ensuing Middle and Late Paleoindian periods.[37]

Whether the Clovis culture drove the mammoth, and other species, to extinction via overhunting – the Pleistocene overkill hypothesis – is still an open, and controversial, theory.[38] It has also been hypothesized that the Clovis culture experienced decline in the wake of the Younger Dryas cold phase.[39] This "cold shock", lasting roughly 1,500 years, affected many parts of the world, including North America. This appears to have been triggered by a vast amount of meltwater – possibly from Lake Agassiz – emptying into the North Atlantic, disrupting the thermohaline circulation.[19]

The Younger Dryas Impact hypothesis, or Clovis Comet hypothesis, originally proposed that a large air burst or earth impact from a comet or comets initiated the Younger Dryas cold period about 12,900 years ago (10,900 14C years ago).[40][18][41] This hypothesis has been largely refuted, with research showing that most of the original findings cannot be replicated by other scientists. This hypothesis is criticized because of its misinterpretation of data and the lack of confirmatory evidence.[42][43][44][45]

Proponents of the hypothesis have responded, disputing the accusation of irreproducibility of their findings.[46][47][48][49][50][51] In 2013, a group from Harvard reported finding a layer of increased platinum (Pt) composition exactly at the Younger Dryas onset in a Greenland ice core, followed in 2017 by a report that the Pt spike had been also been found at an additional 11 continental Younger Dryas sites.[52][53] Since then, the lead author of the Greenland Pt paper has coauthored a comprehensive rebuttal of the impact hypothesis which shows problems with dating and reveals that the Pt anomaly is later than the climate change and therefore could not have caused it.[54]

Discovery edit

On 29 August 1927, the first in place evidence of Pleistocene humans seen by multiple archaeologists in the Americas was discovered near Folsom, New Mexico. At this site they found the first in situ Folsom point with the extinct B. antiquus bones. This confirmation of a human presence in the Americas during the Pleistocene inspired many people to start looking for evidence of early humans.[55] Another earlier example at Folsom was discovered by George McJunkin, a cowboy, who found an ancient bison (Bison antiquus, an extinct relative of the American bison) skeleton in 1908 after a flash flood.[56] The site was first excavated in 1926 under the direction of Harold Cook and Jesse Figgins.

In 1929, 19-year-old Ridgely Whiteman, who had been closely following the excavations in nearby Folsom in the newspaper, discovered the Clovis site near the Blackwater Draw in eastern New Mexico. Despite several earlier Paleoindian discoveries, the best documented evidence of the Clovis complex was collected and excavated between 1932 and 1937 near Clovis, New Mexico, by a crew under the direction of Edgar Billings Howard until 1935 and later by John Cotter from the Academy of Natural Sciences at the University of Pennsylvania. Howard's crew left their excavation in Burnet Cave, the first truly professionally excavated Clovis site, in August, 1932, and visited Whiteman and his Blackwater Draw site. By November, Howard was back at Blackwater Draw to investigate additional finds from a construction project.[57]

The American Journal of Archaeology, in its January–March 1932 edition, mentions E. B. Howard's work in Burnet Cave, including the discovery of extinct fauna and a "Folsom type" point 4 ft below a Basketmaker burial. This brief mention of the Clovis point found in place predates any work done at the Dent site in Colorado. The reference is made to a slightly earlier article on Burnet Cave in The University Museum Bulletin of November, 1931.[58]

The first report of professional work at the Blackwater Draw Clovis site was published in the November 25th issue of Science News (V22 #601) in 1932.[59] The publications on Burnet Cave and Blackwater Draw directly contradict statements by several authors (for example see Haynes 2002:56 The Early Settlement of North America[60]) that Dent, Colorado was the first excavated Clovis site. The Dent site, in Weld County, Colorado, was simply a fossil mammoth excavation in 1932. The first Dent Clovis point was found on November 5, 1932, and the in situ point was found July 7, 1933.[61] The in situ Clovis point from Burnet Cave was excavated in late August, 1931 (and was reported in early 1932).[62]

A Clovis burial site was found in Montana in 1968. It contained the remains of a two-year-old child they named Anzick-1, or Anzick boy. Analysis of DNA recovered from the remains indicates that Anzick-1 is more closely related to all of the indigenous peoples of the Americas than to any other group.[11]

Clovis Paleo-Indians edit

Available genetic data show that the Clovis people are the direct ancestors of roughly 80% of all living Native American populations in North and South America, with the remainder descended from ancestors who entered in later waves of migration.[63][64] As reported in February 2014, DNA from the 12,600-year-old remains of Anzick boy, found in Montana, has affirmed this connection to the peoples of the Americas. In addition, this DNA analysis affirmed genetic connections back to ancestral peoples of northeast Asia. This adds weight to the theory that peoples migrated across a land bridge from Siberia to North America.[23]

Clovis First edit

This theory, known as "Clovis First", had been the predominant hypothesis among archaeologists in the second half of the 20th century. According to Clovis First, the people associated with the Clovis culture were the first inhabitants of the Americas. The primary support for this claim was that no solid evidence of pre-Clovis human habitation had been found. According to the standard accepted theory, the Clovis people crossed the Beringia land bridge over the Bering Strait from Siberia to Alaska during the ice age when there was a period of lowered sea levels, then made their way southward through an ice-free corridor east of the Rocky Mountains, located in present-day Western Canada, as the glaciers retreated.[65]

This hypothesis came to be challenged by ongoing studies that suggest pre-Clovis human occupation of the Americas.[66] In 2011, following the excavation of an occupation site at Buttermilk Creek, Texas, a group of scientists identified the existence "of an occupation older than Clovis."[24][67] At the site in Buttermilk, archaeologists discovered evidence of hunter-gatherer group living and the making of projectile spear points, blades, choppers, and other stone tools. The tools found were made from a local chert and could be dated back to as early as 15,000 years ago.[67]

According to researchers Michael Waters and Thomas Stafford of Texas A&M University, new radiocarbon dates place Clovis remains from the continental United States in a shorter time window beginning 450 years later than the previously accepted threshold (13,200 to 12,900 BP).[21]

Since the early 2010s, the scientific consensus has changed to acknowledge the presence of pre-Clovis cultures in the Americas, ending the "Clovis first" consensus.[68][69][70]

See also edit

References edit

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