Editing Pre-Columbian transoceanic contact theories (section)

=== Sweet potato ===
{{see also|Sweet potato cultivation in Polynesia}}
[[File:Dispersion de la patate douce01.svg|thumb|right|alt=World map showing the spread of sweet potatoes|The spread of sweet potatoes. The red lines indicate the likely spread carried out by the Polynesians.]]
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.<ref>{{cite book |last=Van Tilburg |first=Jo Anne |year=1994 |title=Easter Island: Archaeology, Ecology and Culture |location=Washington DC |publisher=Smithsonian Institution Press}}</ref> 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.<ref>{{cite journal | last1 = Langdon | first1 = Robert | year = 2001 | title = The Bamboo Raft as a Key to the Introduction of the Sweet Potato in Prehistoric Polynesia | journal = The Journal of Pacific History | volume = 36 | issue = 1| pages = 51–76| doi=10.1080/00223340123312}}</ref> It is also possible that the plant floated across the ocean after being discarded from the cargo of a boat.<ref>{{cite journal|title=Modeling the prehistoric arrival of the sweet potato in Polynesia | doi=10.1016/j.jas.2007.04.004 | volume=35|issue=2 |journal=Journal of Archaeological Science|pages=355–367|year=2008 |last1=Montenegro |first1=Álvaro |last2=Avis |first2=Chris |last3=Weaver |first3=Andrew | bibcode=2008JArSc..35..355M }}</ref> 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.<ref>{{cite journal|last1=Roullier |first1=Caroline |first2= Laure |last2=Benoit |first3=Doyle B. |last3=McKey |first4=Vincent |last4=Lebot|title=Historical collections reveal patterns of diffusion of sweet potato in Oceania obscured by modern plant movements and recombination|journal=PNAS|volume=110|issue=6|date=January 22, 2013|doi=10.1073/pnas.1211049110|pmid=23341603|pages=2205–2210|bibcode=2013PNAS..110.2205R|pmc=3568323|doi-access=free}}</ref>

[[File:Thames Kumara n.jpg|thumb|right|Sweet potatoes for sale, Thames, New Zealand. The word "kumara" has entered English from [[Māori language|Māori]] and is widely used, especially in Polynesia.]]

Dutch linguists and specialists in [[Indigenous languages of the Americas|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 language|Proto-Polynesian]] *''kumala''<ref name=POLLEX-kumala>{{cite web|last1=Greenhill|first1=Simon J.|last2=Clark|first2=Ross|last3=Biggs|first3=Bruce|title=Entries for KUMALA.1 [LO] Sweet Potato (Ipomoea)|url=http://pollex.org.nz/entry/kumala1|work=POLLEX-Online: The Polynesian Lexicon Project Online|access-date=July 16, 2013|year=2010|url-status=dead|archive-date=8 February 2013|archive-url=https://web.archive.org/web/20130208114223/http://pollex.org.nz/entry/kumala1/}}</ref> (compare [[Rapa Nui language|Easter Island]] {{lang|rap|kumara}}, [[Hawaiian language|Hawaiian]] {{lang|haw|{{okina}}uala}},<!--this is correct. an [m] was not dropped.--> [[Māori language|Māori]] {{lang|mi|kūmara}}; even though a proto-form is reconstructed above, apparent [[cognate]]s outside [[Eastern Polynesian languages|Eastern Polynesian]] are either definitely [[Loanword|borrowed]] from Eastern Polynesian languages or irregular, calling Proto-Polynesian status and age into question) may be connected with dialectal [[Quechua language|Quechua]] and [[Aymara language|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.<ref>{{cite journal |last1=Sheppard |first1=Peter |date=April 2006 |title=Review of 'The Sweet Potato in Oceania: A Reappraisal' |url=https://www.jstor.org/stable/40387337 |journal=Archaeology in Oceania |volume=41 |issue=1 |pages=46–48 |doi=10.1002/j.1834-4453.2006.tb00608.x |jstor=40387337 |access-date=19 March 2024}}</ref>

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.<ref name="Adelaar2004">{{cite book|first1=Willem F. H. |last1=Adelaar|first2=Pieter C. |last2=Muysekn|title=The Languages of the Andes|chapter-url=https://books.google.com/books?id=UiwaUY6KsY8C&pg=PA41|year= 2004|publisher=Cambridge University Press|isbn=978-1-139-45112-3|page=41|chapter=Genetic relations of South American Indian languages}}</ref>