---
title: "Pre-Columbian transoceanic contact theories"
chunk: 1/11
source: "https://en.wikipedia.org/wiki/Pre-Columbian_transoceanic_contact_theories"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:09:31.175412+00:00"
instance: "kb-cron"
---

Pre-Columbian transoceanic contact theories, many of which are speculative, propose that visits to the Americas, interactions with the Indigenous peoples of the Americas, or both, were made by people from elsewhere prior to Christopher Columbus's first voyage to the Caribbean in 1492. 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. Apart from Norse contact and settlement, 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 multiple  artifacts traded across the Bering Strait have been discovered in pre-Columbian 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archaeological evidence, the discovery of alleged out-of-place artifacts, superficial cultural comparisons, comments in historical documents, or narrative accounts. These have been dismissed as fringe science, pseudoarchaeology, or pseudohistory.

== Claims of Polynesian contact ==

=== Human genetics ===
Between 2007 and 2009, geneticist Erik Thorsby and colleagues published two studies in Tissue Antigens that offer evidence of 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). In 2017, a comprehensive genomes study found "no Native American admixture in pre- and post-European-contact individuals".
Two skulls suggested to belong to "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 14 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 later review paper of Polynesian history suggested that it was "more likely that these are the skulls of two people who died in Polynesia sometime early in the period of European voyaging, and whose graves were robbed by later visitors, and then mistakenly grouped in collections with the remains of Native Americans."
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. Further genetic analysis on Easter Island indigenous population showed about 10% of the genome to be of Native American origin.

=== Plant genetics ===
The genetics of several plant species has also been used to support pre-Columbian contact via the Pacific. For example, there is a genetically distinct sub-population of coconuts on the western coast of South America. This has been suggested to be evidence of introduction by Austronesian seafarers.

=== 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. According to the "tripartite hypothesis", phylogenetic analysis supports at least two separate introductions of sweet potatoes from South America into Polynesia, including one before and one after European contact.