
Examples of Clovis and other Paleoindian point forms, markers of archaeological cultures in northeastern North America.
The
Solutrean hypothesis proposes that stone tool technology of the
Solutrean culture in prehistoric Europe may have later influenced the development of the
Clovis tool-making culture in the Americas, and that peoples from Europe may have been among the earliest settlers in the Americas. It was first proposed in 1998. Its key proponents include
Dennis Stanford, of the
Smithsonian Institution, and Bruce Bradley, of the
University of Exeter.
In this hypothesis, peoples associated with the Solutrean culture migrated from
Ice Age Europe to
North America, bringing their methods of making stone tools with them and providing the basis for later Clovis technology found throughout North America. The hypothesis rests upon particular similarities in Solutrean and Clovis technology that have no known counterparts in Eastern Asia,
Siberia or
Beringia, areas from which or through which early Americans are known to have migrated.
Characteristics
Solutrean culture was dominant in present-day
France and
Spain from roughly 21,000 to 17,000 years ago. It was known for its distinctive toolmaking characterized by
bifacial, pressure-flaked points. Traces of the Solutrean tool-making industry disappear completely from Europe around 15,000 years ago, when it was replaced by the less complex stone tools of the
Magdalenian culture.
Clovis tools are typified by a distinctive rock
spear point, known as the
Clovis point. Solutrean and Clovis points share common characteristics: points are thin and bifacial, and they share the intentional use of the overshot flaking technique, which quickly reduces the thickness of a biface.
The Clovis blade differs from its predecessor in that it has bi-facial fluting (a long depression that occurs on a point, which is caused by
knapping at the basal end of the point; the purpose was to fit the point onto a spear foreshaft). Clovis tool-making technology seems to appear in the archaeological record in North America roughly 13,500 years ago, and similar predecessors in Asia or Alaska, if they exist, have not been discovered.
Atlantic crossing

Water temperatures during the last glacial maximum, according to
CLIMAP.
The hypothesis proposes that
Ice Age Europeans could have crossed the North Atlantic along the edge of the pack ice that extended from the Atlantic coast of France to
North America during the
last glacial maximum. The model envisions these people making the crossing in small watercraft, using skills similar to those of the modern
Inuit people, hauling out on ice floes at night, getting fresh water by melting
iceberg ice or the first-frozen parts of
sea ice, getting food by catching seals and fish, and using
seal blubber as heating fuel. Among other evidence backing up this hypothesis is the discovery among the Solutrean toolkit of bone needles, very similar to those traditionally used by the modern-day
Inuit. As well as enabling the manufacture of waterproof clothing from animal skins, the technology could, in theory, have been used to construct
kayaks from the same animal skins. However, a 2008 study (see below) argues that the conditions were not favorable for such a crossing.
Transitional styles
Supporters of the hypothesis suggest that stone tools found at
Cactus Hill (an early American site in Virginia) indicate a transitional style between the Clovis and Solutrean cultures. Artifacts from this site are estimated to date from 17,000 to 15,000 years ago, although some researchers dispute their definitive age. Other sites that may indicate transitional, pre-Clovis occupation include the
Page-Ladson site in
Florida and the
Meadowcroft rockshelter in
Pennsylvania.
MtDNA Haplogroup X
Mitochondrial DNA analysis lends conditional support to the idea insofar as the fact that some members of some native North American tribes share a common yet distant maternal ancestry with some present-day individuals in Europe identified by mtDNA
Haplogroup X. It is possible that Haplogroup X came to the Americas via Northeastern Asia or Siberia, but unlike other Native American mtDNA Haplogroups
A,
B,
C and
D, Haplogroup X is presently absent from the region, although occurrence of Haplogroup X2 of more recent origin (i.e. more recently than 5000 BC) has been identified in the
Altai Republic.
The
New World haplogroup X DNA (now called subgroup X2a) is as different from any of the
Old World X2 lineages as they are from each other, indicating a very ancient origin. Although haplogroup X occurs only at a frequency of about 3% for the total current indigenous population of the Americas, it is a major haplogroup in northeastern North America, where among the
Algonquian peoples of the Great Lakes Region it allegedly comprises up to 25% of mtDNA types. It has been suggested that its relative concentration in northeastern North America indicates an early North Atlantic route for bearers of this haplotype, although it is found in smaller percentages in other regions, among the
Sioux,
Nuu-Chah-Nulth, and
Yakama in western North America as well as the
Yanomamö in
Brazil.
Recent Genetic Research
An article in the
American Journal of Human Genetics by researchers in Brazil argued against the Solutrean hypothesis. "Our results strongly support the hypothesis that haplogroup X, together with the other four main mtDNA haplogroups, was part of the gene pool of a single Native American founding population; therefore they do not support models that propose haplogroup-independent migrations, such as the migration from Europe posed by the Solutrean hypothesis."
Challenges to the Solutrean hypothesis
Arthur J. Jelinek, an anthropologist who noted similarities between Solutrean and Clovis styles in a 1971 study, noted that the great geographical and temporal separation of the two cultures made a direct connection unlikely. He also noted that crossing the Atlantic with the technology of the time would have been difficult if not impossible, an observation repeated by Lawrence G. Straus. Others have pointed to a lack of evidence of Solutrean seafaring. Proponents point out that evidence of Solutrean-era seafaring may have been obliterated or buried underwater, as much of the coastlines of western Europe and eastern North America that existed during the Last Glacial Maximum are now submerged. However, Straus excavated Solutrean artifacts along what is now a coastline in
Cantabria, which was not coastal at the time of Solutreans, finding seashells and estuarine fish at the sites, but no evidence of exploiting deep sea resources. In addition, the dates of the proposed transitional sites and the Solutrean period in Europe only overlap at the extremes.
Other challenges to the hypothesis include a lack of Solutrean-style artwork (like that found at
Altamira in Spain and
Lascaux in France) among the Clovis people. In response, proponents point out that this style of art disappears in Europe by the time of Clovis, and that the Solutreans introduced a tool-making innovation and not necessarily cultural or artistic practices.
In a 2008 study of the relevant paleoceanographic data, Kieran Westley and Justin Dix concluded that "it is clear from the paleoceanographic and paleo-environmental data that the LGM North Atlantic does not fit the descriptions provided by the proponents of the Solutrean Atlantic Hypothesis. Although ice use and sea mammal hunting may have been important in other contexts, in this instance, the conditions militate against an ice-edge-following, maritime-adapted European population reaching the Americas."
See also