Scientists Built a Canoe Using Only Prehistoric Tools. Then They Sailed the Dangerous 140-Mile Route Early Humans Traveled 30,000 Years Ago
Five paddlers journeyed from Taiwan to Japan’s southern Yonaguni Island in 45 hours. Their efforts provide new insights into prehistoric mariners’ tools and techniques
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Some 30,000 years ago, humans sailed 140 miles from Taiwan to Japan’s southern Yonaguni Island, navigating the Pacific Ocean’s powerful Kuroshio currents. But how exactly did they manage to complete such a difficult voyage?
To answer that question, a team of Japanese researchers recreated the trip. In 2019, they made a 25-foot-long canoe from a cedar log and launched it from eastern Taiwan. Navigating only by the wind, sun and stars, they made it to Yonaguni in 45 hours.
The team details their project in two new studies published in Science Advances: One describes the researchers’ numerical simulations, while the other describes their journey.
Quick fact: Another experiment that shed light on prehistoric seafaring
In 2000, researchers sailed a bamboo boat from Bali to the nearby island of Lombok.
“Before our project, no one had seriously considered how this maritime migration occurred,” lead author Yousuke Kaifu, an anthropologist at the University of Tokyo, tells Scientific American’s Nora Bradford.
The researchers wanted to find out just how difficult the journey was. They were also interested in the tools and strategies that prehistoric mariners may have used.
“Archaeological evidence such as remains and artifacts can’t paint a full picture, as the nature of the sea is that it washes such things away,” Kaifu says in a statement from the University of Tokyo. “So we turned to the idea of experimental archaeology, in a similar vein to the Kon-Tiki expedition of 1947 by Norwegian explorer Thor Heyerdahl.”
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Kaifu is referring to Heyerdahl’s experimental voyage from Peru to Polynesia, which he performed with five crewmembers on a raft made of balsa wood in the late 1940s. Aiming to confirm his theory that prehistoric humans may have sailed across the Pacific, Heyerdahl and his crew traversed thousands of nautical miles in their raft, which they called Kon-Tiki.
The Japanese researchers used their simulations to discern that a dugout canoe would have been the most likely vessel used by Paleolithic humans. They’d initially hypothesized that these mariners used rafts, but rafts turned out to be too slow for the Kuroshio current, as Kaifu explains in the statement.
The simulations also helped determine the time and location of the researchers’ launch. “We tested various seasons, starting points and paddling methods under both modern and prehistoric conditions,” Kaifu tells the New York Times’ Franz Lidz.
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They constructed their canoe, called Sugime, using stone axes. Then, in July 2019, a team of one woman and four men set out for Yonaguni. They didn’t use maps during their crossing, and they often couldn’t see their destination in the distance, per the Times.
Still, the canoe was “speedy and durable enough to cross this strait,” the researchers write, suggesting both that the prehistoric humans had developed functional boats and “that this type of sea travel was possible only for experienced paddlers with advanced navigational skills.”
“The Kuroshio current is generally considered dangerous to navigate,” says co-author Yu-Lin Chang, a scientist at the Japan Agency for Marine-Earth Science and Technology, in the statement. “I thought if you entered it, you could only drift aimlessly. But the results of our simulations went far beyond what I had imagined.”
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Still, the current’s strength likely made a return journey impossible for the prehistoric mariners, as Kaifu says in the statement.
As Helen Farr, a maritime archaeologist at the University of Southampton in England who wasn’t involved in the research, tells Scientific American, such test voyages can help reveal lost histories of human migration.
“You suddenly see a level of skill and planning that is really hard to see in the archaeological record for this time period,” she says. “So to get an insight into an activity—a temporal, spatial, specific activity like seafaring in this region—and just the little human details that you get from it, that’s what is a real, real joy.”
