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Drifters could explain sweet-potato travel

An unsteered ship may have delivered crop to Polynesia.

How did the South American sweet potato wind up in Polynesia? New research suggests that the crop could have simply floated there on a ship.

Read the story here.

Posted by Nicola Jones on May 18, 2007 05:32 PM |

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The Kon-Tiki expedition

The balsa wood raft Kon-Tiki was built as a copy of a prehistoric South American vessel. Constructed of nine balsa logs collected from Ecuador, a crew of six men sailed the raft from Callao in Peru on 28 April 1947 and landed on the island of Raroia in Polynesia after 101 days. This successful voyage of around 4,300 miles proved that the islands in Polynesia were within the range of this type of prehistoric South American vessel. A documentary of the voyage won an Oscar in 1951 and the book about the expedition has been translated into no fewer than 66 languages.

From Kon-Tiki museum
http://www.kon-tiki.no/

More on Kon-Tiki expedition and Thor Heyerdahl
http://en.wikipedia.org/wiki/Kon-Tiki

Posted by: Eyal Morag | May 18, 2007 10:25 PM

I think Thor Heyerdahl settled the question of the possibility of such travel by boat (or log raft) in his 1947 Kon-Tiki expedition. He carried both the sweet potato and the bottle gourd with him. See http://en.wikipedia.org/wiki/Kon_tiki

Posted by: George Johnson | May 19, 2007 08:44 PM

Well, gee, Thor Heyerdahl covered this pretty well in his late-1940's book Kon Tiki. His exploration was based on the fact that the Polynesian legends held that the islands had been settled by people from S. America while Inca legends told of a people who had been driven out of South America and had gone west into the Pacific. Heyerdahl mentioned the sweet potato, which the Polynesians said had been brought to their islands with the original settlers as well as the similarity in the names for the sweet potato. He also mentioned, as I recollect, a type of gourd for carrying water, coconuts / palm trees, and a marked similarity between carved stone monoliths in Peru, the stone heads on Easter Island, and carved stone figures found on some of the easternmost islands of Polynesia.

His voyage, and his theory of the settlement of Polynesia, was based on legends he learned from both the islanders and legends the Spanish had recorded from the Inca.

It has always struck me as odd how little credence modern academics and scholars give to the legends of other peoples in spite of the fact that time after time the legends prove to be true, but, maybe that is just me.

Thor Heyerdahl's Kon Tiki. For what it is worth.

Posted by: Erich Sturn | May 19, 2007 11:55 PM

When trying to track floating debris at sea you must take into consideration the prevading winds affect on the sea's surface. You don't have to have freeboard to be wind driven. In fact the wind will affect both the freeboard and the water so both effects have to be taken into account. I am an ex Royal Air Force search and rescue navigator and all these individual vectors had to be taken into consideration when trying to find survivors at sea.

Posted by: John Marshall | May 20, 2007 11:41 AM

Thor Heyerdahl must be groaning in his grave.

Posted by: ted crossley | May 21, 2007 06:04 AM

Sweet potato tubers won't propogate on a beach. The theory fails to account for propogation post-arrival. An unsteered (unmanned) ship is about as likely the cause for migration of such tubers as the notion that after reaching a beach the tubers found soil in which to propogate by themselves.
Coconuts can grow on a beach without human help but people had to plant the tubers in places where they would grow -

Posted by: Ken Robinson | May 21, 2007 02:33 PM

The Kon-Tiki demonstrated that it was possible to use prehistoric S. American ships to get to the islands, and archaeologists are pretty confident S. American people travelled to the Galapagos. However, there is no hard evidence that they made it any further.

As Pat Kirch points out, most folks involved in the debate think the Polynesians made a journey to the S. American coast and returned to the Pacific with the sweet potato -- which must have reminded them of the Chinese yam. Although the idea is logical and consistent with present evidence, there's no hard evidence that such a journey actually took place. The sweet potato has been used to support their case, but as Montenegro shows in this study it also could have just drifted there without a human pilot -- perhaps on a vessel just like the Kon-Tiki.

Posted by: Brendan Borrell | May 21, 2007 02:57 PM

Perhaps it was migratory African sparrows.

Posted by: Bombadil | May 21, 2007 05:29 PM

However, I would guess that transfer of the tuber "by accident" would have been near impossible without somebody hanging a sign on it - calling it by its South American name - and a Polynesian discoverer being able to read the written name and being able to get the correct pronunciation - as the Polynesians had no written record. Don´t know about the South American Indians.

It is amazing, however to see the same name all over Polynesia - kumara in Rapa Nui (Easter Island), úala in Hawaií and so forth - all identical.

To translate Rapa Nui to Hawaiian - replace the "k" that the apostrophe indicates (in the Hawaiian) and replace the "r" with a "k". Close enough?

ku

Posted by: ku ching | May 21, 2007 06:36 PM

Brendan - can you give more info on Kirch's thoughts on these contacts? Or some cites? I'd love to hear more of what Dr. Kirch has to say about pre-Eurpoean contact Polynesia, especially Hawaii.

Posted by: martha h noyes | May 21, 2007 11:25 PM

There is no archaeological evidence that prehistoric South Americans ever reached the Galapagos.
The archaeological, linguistic, and human biological evidence shows that all islands now settled by Polynesians were only ever settled by them. there is no evidence of South American presence.
One might expect these new researchers to have carried out some experiments as to the long-term viability of sweet potato drifitng in boats and then establishing itself on some Pacific island. This research sounds to me like ipomoea pie in the sky.

Posted by: Peter White | May 22, 2007 02:57 AM

Why is it that anthropologists refuse to give any but our most recent ancestors credit for having ingenuity, capability and curiosity? I find it inane to imagine that people sat on the Pacific coasts of South America for a thousand generations and not one of them ever wondered what was beyond the horizon! Not one of them, even though they fished those waters daily, ever got up nerve enough to sail beyond the sight of land? That just flies in the face of all we know about the human mind and spirit!

Posted by: JD RICKS | May 23, 2007 05:17 AM

Why go to all this trouble considering ocean currents? The Quechua (Peru) word for the sweet potato is /kumar/. The polynesian word is /kumala/. (Source: Untangling Oceanic settlement: the edge of the knowable, Hurles, Matisoo-Smith, Gray and Penny, Trends in ecology and evolution, Vol 18, No 10, October 2003 p531ff)

The polynesians are known to have sailed north and south, east and west across the Pacific, reaching Hawaii, Easter Island and New Zealand. South Americans are not known to have sailed any great distance at all. The native Americans had plenty of land to settle- why expect them to have sailed over the sea against the prevailing winds into a wide ocean?

Posted by: Ross Marks | May 24, 2007 05:44 AM

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