The Stone Age may have to be renamed following the discovery that early humans were building wooden structures nearly half a million years ago, archaeologists have said.

Two planks of worked wood dating back at least 476,000 years, which possibly formed the foundation of a home, have been found at Kalambo Falls in Zambia.

It is the oldest wooden structure discovered in the world, and was probably built not by Homo sapiens, but by our far older ancestor Homo heidelbergensis.

Not only does it challenge previous assumptions that humans only began making wooden structures in around 9,000 BC, the find also suggests our ancestors may not have been nomadic hunter gatherers after all.

Experts believe the structure could have been a walkway, a raised platform or even a house, indicating early humans settled in the area and considered it home.

Prof Larry Barham, from the University of Liverpool’s department of archaeology, classics and Egyptology, said: “This find has changed how I think about our early ancestors.

“Forget the label Stone Age, look at what these people were doing. They made something new, and large, from wood.

“Until this point you had Neanderthals using wood from branches to make spears and roots, and throwing sticks and digging sticks, but as far as we know they didn’t use it as a raw material.”

“These folks were more like us than we thought. They transformed their surroundings to make life easier, even if it was only by making a platform to sit on by the river to do their daily chores.

“They used their intelligence, imagination, and skills to create something they’d never seen before, something that had never previously existed.”

He added: “We might have to abandon the term Stone Age, because we now know that they were working with stone, bone and wood.”

The Kalambo Falls site, on the Kalambo River, lies above a 772ft waterfall on the border between Zambia and Tanzania.

‘Humble role’ of wood in the human story

Experts say that visible tool marks show the two planks had been modified to fit together in a single interlocking structure.

A notch had been carved into the upper log to allow it to slot into the plank beneath, while the bottom plank’s end was flattened into a thin wedge, possibly to fit into something else.

A similar pair was found by the archaeologist Denmond Clark in the 1960s, but the team was unable to date them. It suggests many of the planks may once have been fitted together to form a wooden platform.

A team at Aberystwyth University used new luminescence dating techniques, which reveal the last time minerals in the sand surrounding the finds were exposed to sunlight, to determine their age.

Prof Geoff Duller, from Aberystwyth University, said: “At this great age, putting a date on finds is very challenging and we used luminescence dating to do this.

“These new dating methods have far-reaching implications, allowing us to date much further back in time, to piece together sites that give us a glimpse into human evolution.

“The site at Kalambo Falls had been excavated back in the 1960s when similar pieces of wood were recovered, but they were unable to date them, so the true significance of the site was unclear until now.

“Our research proves that this site is much older than previously thought, so its archaeological significance is now even greater.”

Although animals are known to build nests or dams out of wood, they do not modify logs or sticks to help them fit together.

Wood is notoriously tricky to find in the archaeological record, and the planks were only preserved because they had remained in a waterlogged environment cut off from oxygen.

Until the new discovery, the earliest evidence of wooden platforms came from Star Carr, a Mesolithic site dating from around 9,000 BC, near Scarborough in North Yorkshire.

Annemieke Milks, from the department of archaeology at the University of Reading, said: “Studies such as this one highlight the role of this most humble of materials in the human story, and simultaneously reveal when people started to structurally alter the planet for their own benefit.”

The find was reported in the journal Nature.