When were boats invented?

Around 8000 B.C., a canoe carved from a single pine log came to rest in what is now the Netherlands. The roughly 10-foot-long (3 meters) boat wasn't discovered until 1955, when a road crew unearthed it from a peat bog near the village of Pesse. The artifact, now known as the Pesse canoe, is the world's oldest physical example of a boat.

But there is significant indirect evidence that humans have been using boats for much longer than 10,000 years. So exactly when did humans invent boats?

It is widely accepted that humans have been using boats at least since Homo sapiens arrived in Australia, according to Mikael Fauvelle, an associate professor and researcher in the Department of Archaeology and Ancient History at Lund University in Sweden.

"We have solid evidence that humans were in modern-day Australia between 50,000 and 65,000 years ago," Fauvelle told Live Science via email. "This would have required open-ocean seafaring between mainland Asia and the paleocontinent of Sahul (of which Australia was then a part). Some sort of watercraft, therefore, must have been in use by at least circa 50,000 years ago."

The evidence in this case is not from the physical remains of an ancient boat. Instead, it comes from DNA: A recent study analyzed almost 2,500 genomes from ancient and contemporary Aboriginal people throughout Australia and nearby countries, and investigated when Australian populations diverged from those on other continents. Their statistical models suggested that northern Australia was first settled around 60,000 years ago. Those findings also line up with contemporaneous tools and pigments unearthed at Australian dig sites.

Other, more controversial archaeological evidence raises the possibility that humans were seafaring much earlier.

"There is some tantalizing evidence from Greece," Fauvelle said. "Paleolithic stone tools found on Crete have been dated based on their find-context to [at least] 130,000 years ago. Some archaeologists have disputed these dates, but if they hold up, it would mean that ancient humans would have traveled there by boat during the Middle Holocene." Crete is dozens of miles from mainland Greece (and has been an island for about 5 million years).

Some experts would push back the clock on sea travel by hundreds of thousands of years, if not over a million, which would mean boats predate our species.

A 1998 study led by archaeologist Michael Morwood dated stone tools found on the Indonesian island of Flores to about 800,000 years ago and concluded that Homo erectus may have used watercraft to get there. Morwood later co-authored a 2010 study that found tools from a different site in Flores may have originated 1.02 million years ago, if not earlier. And in a study published last year in the journal Nature, a different research team proposed that pieces of stone tools found on the nearby Indonesian island of Sulawesi suggest ancient human relatives were crafting tools there at least 1.04 million years ago.

Still, there is plenty of debate about how and when ancient human relatives arrived on those islands. John Cherry, a professor emeritus of archaeology at Brown University, said one problem with the stone artifacts from Crete is that they are "surface finds," which sit in plain sight above ground, as opposed to "stratified" objects, which are found in distinct soil layers. They are also "lacking absolute radiometric dates," which could further clarify when the tools were built. If the data in Crete "stand up to further scrutiny, or can be better dated," we can draw better conclusions, he told Live Science in an email.

The studies in Indonesia "are all very solid," Cherry told Live Science. But he hypothesizes that hominins reached Flores and Sulawesi accidentally. "Basically, a chunk of land with vegetation on it breaks away from the mainland," potentially during flooding from monsoons or rivers and are "carried by the currents and the winds out into the ocean itself," Cherry explained.

He pointed to a 2025 study that suggested some iguanas may have rafted 5,000 miles (8,000 kilometers) from North America to Fiji.

"We know it happened with thousands of other species, including primates such as monkeys and lemurs, so why not humans?" Cherry said. In addition, the hominins in Flores and Sulawesi were most likely H. erectus, and "orthodox understanding of human evolution makes it unlikely that [H.] erectus had the requisite social structures, communication capabilities, or complex additive technologies necessary for undertaking sea crossings," he added.

No matter when ancient humans did set to sea, there is still the question of what drove them to do so. Fauvelle has a few ideas. One was the search for food.

"Aquatic environments are full of rich food resources. … It is highly likely that many early experiments with watercraft on lakes, rivers, or estuaries were for the purposes of fishing or gathering other aquatic food resources," Fauvelle said. Boats also would have been "the best tools available for easily transporting large amounts of material," such as "large animal carcasses from hunting grounds back home, or for the transportation of flint or obsidian from stone quarries."

And perhaps humans have always had a drive to explore the unknown.

"There has been a strong tendency throughout human history to explore new regions, and in many instances such exploration was done by boat," Fauvelle said. "If you are moving to a new region with your family you likely need to bring many things with you, and the logistical capacities of boats would greatly facilitate such travel."

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