Pre-Columbian Africa-Americas contact theories

Pre-Columbian transoceanic contact theories are speculative theories which propose that possible visits to the Americas, possible interactions with the indigenous peoples of the Americas, or both, were made by people from Africa, Asia, Europe, or Oceania prior to Christopher Columbus's first voyage to the Caribbean in 1492 (i.e., during any part of the pre-Columbian era). Studies between 2004 and 2009 suggest the possibility that the earliest human migrations to the Americas may have been made by boat from Beringia and travel down the Pacific coast, contemporary with and possibly predating land migrations over the Beringia land bridge, which during the glacial period joined what today are Siberia and Alaska. Whether transoceanic travel occurred during the historic period, resulting in pre-Columbian contact between the settled American peoples and voyagers from other continents, is vigorously debated.

Only a few cases of pre-Columbian contact are widely accepted by mainstream scientists and scholars. Yup'ik and Aleut peoples residing on both sides of the Bering Strait had frequent contact with each other, and Eurasian trade goods have been discovered in archaeological sites in Alaska. Maritime explorations by Norse peoples from Scandinavia during the late 10th century led to the Norse colonization of Greenland and a base camp L'Anse aux Meadows in Newfoundland, which preceded Columbus's arrival in the Americas by some 500 years. Recent genetic studies have also suggested that some eastern Polynesian populations have admixture from coastal western South American peoples, with an estimated date of contact around 1200 CE.

Scientific and scholarly responses to other claims of post-prehistory, pre-Columbian transoceanic contact have varied. Some of these claims are examined in reputable peer-reviewed sources. Many others are based only on circumstantial or ambiguous interpretations of archaeological evidence, the discovery of alleged out-of-place artifacts, superficial cultural comparisons, comments in historical documents, or narrative accounts. They have been dismissed as fringe science, pseudoarchaeology, or pseudohistory.

Norse colonization of the Americas

Norse journeys to Greenland and Canada prior to Columbus's voyages are supported by historical and archaeological evidence. A Norse colony was established in Greenland in the late 10th century and lasted until the mid-15th century, with court and parliament assemblies ('' þing'') taking place at Brattahlíð and a bishop being posted at Garðar. The remains of a Norse settlement used as a base-camp at L'Anse aux Meadows in what is now Newfoundland, a large island on the Atlantic coast of Canada, were discovered in 1960 and have been radiocarbon-dated to between 990 and 1050 CE. More recently, tree-ring analysis of structures at the site have been dated to the year 1021.

This remains the only site widely accepted as evidence of post-prehistory, pre-Columbian trans-oceanic contact with the Americas. L'Anse aux Meadows was named a World Heritage Site by UNESCO in 1978. It is also possibly connected with the attempted colony of Vinland established by Leif Erikson around the same period or, more broadly, with Norse exploration of the Americas.

Though L'Anse aux Meadows establishes that Norse colonists traveled to and built permanent structures in North America, few sources describing contact between indigenous peoples and Norse people exist. Contact between the Thule people (ancestors of the modern Inuit) and Norse in the 12th or 13th century is known. The Norse Greenlanders called these native people " skrælingar". Conflict between the Greenlanders and the "skrælings" is recorded in the ''Icelandic Annals''. The term ''skrælings'' is also used in the Vínland sagas, which relate to events during the 10th century, when describing trade and conflict with native peoples.

Polynesian, Melanesian, and Austronesian contact

Genetic studies

Between 2007 and 2009, geneticist Erik Thorsby and colleagues published two studies in ''Tissue Antigens'' that evidence an Amerindian genetic contribution to human populations on Easter Island, determining that it was probably introduced before European discovery of the island. In 2014, geneticist Anna-Sapfo Malaspinas of The Center for GeoGenetics at the University of Copenhagen published a study in '' Current Biology'' that found human genetic evidence of contact between the populations of Easter Island and South America, dating to approximately 600 years ago (i.e. 1400 CE ± 100 years).

Two remains of "Botocudo" people (a term used to refer to Native Americans who live in the interior of Brazil that speak Macro-Jê languages), were found in research published in 2013 to have been members of mtDNA haplogroup B4a1a1, which is normally found only among Polynesians and other subgroups of Austronesians. This was based on an analysis of fourteen skulls. Two belonged to B4a1a1, while twelve belonged to subclades of mtDNA haplogroup C1 (common among Native Americans). The research team examined various scenarios, none of which they could say for certain were correct. They dismissed a scenario of direct contact in prehistory between Polynesia and Brazil as "too unlikely to be seriously entertained." While B4a1a1 is also found among the Malagasy people of Madagascar (which experienced significant Austronesian settlement in prehistory), the authors described as "fanciful" suggestions that B4a1a1 among the Botocudo resulted from the African slave trade (which included Madagascar). A 2020 study strongly questioned the premise of the paper as being based on outdated racial classifications.

In 2020, a study in ''Nature'' found that populations in the Mangareva, Marquesas, and Palliser islands and Easter Island had genetic admixture from indigenous populations of South America, with the DNA of contemporary populations of Zenú people from the Pacific coast of Colombia being the closest match. The authors suggest that the genetic signatures were probably the result of a single ancient contact. They proposed that an initial admixture event between indigenous South Americans and Polynesians occurred in eastern Polynesia between 1150 and 1230 CE, with later admixture in Easter Island around 1380 CE, but suggested other possible contact scenarios—for example, Polynesian voyages to South America followed by Polynesian people's returning to Polynesia with South American people, or carrying South American genetic heritage. Several scholars uninvolved in the study suggested that a contact event in South America was more likely.

Sweet potato

The sweet potato, a food crop native to the Americas, was widespread in Polynesia by the time European explorers first reached the Pacific. Sweet potato has been radiocarbon-dated to 1000 CE in the Cook Islands. Current thinking is that it was brought to central Polynesia c. 700 CE and spread across Polynesia from there. It has been suggested that it was brought by Polynesians who had traveled across the Pacific to South America and back, or that South Americans brought it to Polynesia. It is also possible that the plant floated across the ocean after being discarded from the cargo of a boat. Phylogenetic analysis supports the hypothesis of at least two separate introductions of sweet potatoes from South America into Polynesia, including one before and one after European contact.

Dutch linguists and specialists in Amerindian languages Willem Adelaar and Pieter Muysken have suggested that the word for sweet potato is shared by Polynesian languages and languages of South America. Proto-Polynesian *''kumala'' (compare Easter Island ''kumara'', Hawaiian ''uala'', Māori ; even though a proto-form is reconstructed above, apparent cognates outside Eastern Polynesian are either definitely borrowed from Eastern Polynesian languages or irregular, calling Proto-Polynesian status and age into question) may be connected with dialectal Quechua and Aymara ''k'umar ~ k'umara''; most Quechua dialects actually use ''apichu'' instead, but ''comal'' was attested at extinct Cañari language on the coast of what is now Ecuador in 1582.

Adelaar and Muysken assert that the similarity in the word for sweet potato "constitutes near proof of incidental contact between inhabitants of the Andean region and the South Pacific." The authors argue that the presence of the word for sweet potato suggests sporadic contact between Polynesia and South America, but not necessarily migrations.

''Ageratum conyzoides''

''Ageratum conyzoides'', also known as billygoat-weed, chick weed, goatweed, or whiteweed, is native to the tropical Americas, and was found in Hawaii by William Hillebrand in 1888 who considered it to have grown there before Captain Cook's arrival in 1778. A legitimate native name (''meie parari'' or ''mei rore'') and established native medicinal usage and use as a scent and in leis have been offered as support for the pre-Cookian age.

Turmeric

Turmeric (''Curcuma longa'') originated in Asia, and there is linguistic and circumstantial evidence of the spread and use of turmeric by the Austronesian peoples into Oceania and Madagascar. Günter Tessmann in 1930 (300 years after European contact) reported that a species of ''Curcuma'' was grown by the Amahuaca tribe to the east of the Upper Ucayali River in Peru and was a dye-plant used for the painting of the body, with the nearby Witoto people using it as face paint in their ceremonial dances. David Sopher noted in 1950 that "the evidence for a pre-European, transpacific introduction of the plant by man seems very strong indeed".

Physical anthropology

In December 2007, several human skulls were found in a museum in Concepción, Chile. These skulls originated on Mocha Island, an island which is located just off the coast of Chile on the Pacific Ocean, formerly inhabited by the Mapuche. Craniometric analysis of the skulls, according to Lisa Matisoo-Smith of the University of Otago and José Miguel Ramírez Aliaga of the Universidad de Valparaíso, suggests that the skulls have " Polynesian features" – such as a pentagonal shape when they are viewed from behind, and rocker jaws.

Rocker jaws have also been found at an excavation led José Miguel Ramírez in the coastal locality of Tunquén, Central Chile. The site of excavation corresponds to an area with pre-Hispanic tombs and shell middens ( es, conchal). A global review of rocker jaws among different populations show that while rocker jaws are not unique to Polynesians " e rarity of rocker jaw in South American natives supports" the view of "Polynesian voyagers who ventured to the west coast of South America".

Disputed evidence

Araucanian chickens

In 2007, evidence emerged which suggested the possibility of pre-Columbian contact between the Mapuche people (Araucanians) of south-central Chile and Polynesians. Bones of Araucana chickens found at El Arenal site in the Arauco Peninsula, an area inhabited by Mapuche, support a pre-Columbian introduction of landraces from the South Pacific islands to South America. The bones found in Chile were radiocarbon-dated to between 1304 and 1424, before the arrival of the Spanish. Chicken DNA sequences were matched to those of chickens in American Samoa and Tonga, and found to be dissimilar to those of European chickens.

However, this finding was challenged by a 2008 study which questioned its methodology and concluded that its conclusion is flawed, although the theory it posits may still be possible. Another study in 2014 reinforced that dismissal, and posited the crucial flaw in the initial research: "The analysis of ancient and modern specimens reveals a unique Polynesian genetic signature" and that "a previously reported connection between pre-European South America and Polynesian chickens most likely resulted from contamination with modern DNA, and that this issue is likely to confound ancient DNA studies involving haplogroup E chicken sequences."

However, in a 2013 study, the original authors extended and elaborated their findings, concluding:

A 2019 study of South American chickens "revealed an unknown genetic component that is mostly present in the Easter Island population that is also present in local chicken populations from the South American Pacific fringe". The Easter Island chicken's "genetic proximity with the SA continental gamefowl can be explained by the fact that both populations were not crossed with cosmopolitan breeds and therefore remain closer to the ancestral population that originated them. " The genetic proximity might also "be indicative of a common origin of these two populations".

California canoes

Researchers including Kathryn Klar and Terry Jones have proposed a theory of contact between Hawaiians and the Chumash people of Southern California between 400 and 800 CE. The sewn-plank canoes crafted by the Chumash and neighboring Tongva are unique among the indigenous peoples of North America, but similar in design to larger canoes used by Polynesians and Melanesians for deep-sea voyages. '' Tomolo'o'', the Chumash word for such a craft, may derive from ''tumula'au''/''kumula'au'', the Hawaiian term for the logs from which shipwrights carve planks to be sewn into canoes. The analogous Tongva term, ''tii'at'', is unrelated. If it occurred, this contact left no genetic legacy in California or Hawaii. This theory has attracted limited media attention within California, but most archaeologists of the Tongva and Chumash cultures reject it on the grounds that the independent development of the sewn-plank canoe over several centuries is well-represented in the material record.

Clava hand-club and words for axes

Archaeological artefacts known as clava hand-clubs found in Araucanía and nearby areas of Argentina have a strong resemblance to the mere okewa found in New Zealand. The clava hand-clubs are also mentioned in the Spanish chronicles dating to the Conquest of Chile. According to Grete Mostny, clava hand-clubs "appear to have arrived to the west coast of South America from the Pacific". Polynesian clubs from Chatham Islands are reportedly the most similar to those of Chile. The clava hand-club is one of various Polynesian-like Mapuche artifacts known.

On Easter Island, the word for a stone axe is '' toki''; among the New Zealand Maori, the word ''toki'' denotes an adze; in the Mapuche language of Chile and Argentina, the word for a stone axe is ''toki''; and further afield in Colombia, the Yurumanguí word for an axe is ''totoki''. The Mapuche word ''toki'' may also mean "chief" and thus may be related to the Quechua word ''toqe'' ("militia chief") and the Aymara word ''toqueni'' ("person of great judgement"). In the view of Moulian et al. (2015) the possible South American links complicate matters regarding the meaning of the word ''toki'' because they are suggestive of Polynesian contact.

Claims of East Asian contact

Claims of contact with Ecuador

A 2013 genetic study suggested the possibility of contact between Ecuador and East Asia, that would have happened no earlier than 6,000 years ago (4000 BC) via either a trans-oceanic or a late-stage coastal migration that did not leave genetic imprints in North America. Further research did not support this but was rather "a case of a rare founding lineage that has been lost elsewhere by drift."

Claims of Chinese contact

Some researchers have argued that the Olmec civilization came into existence with the help of Chinese refugees, particularly at the end of the Shang dynasty. In 1975, Betty Meggers