Science

Oldest wooden structure, half a million years old, predates our species

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Archaeologists excavating the oldest known wooden structure, dating back around 476,000 years
Professor Larry Barham, University of Liverpool
Archaeologists excavating the oldest known wooden structure, dating back around 476,000 years
Professor Larry Barham, University of Liverpool
The discovery of the ancient wooden structure was made at the archaeological site of Kalambo Falls in Zambia
Professor Larry Barham, University of Liverpool
The structure is made up of two logs cut and crafted into a kind of cross-shape
Professor Larry Barham, University of Liverpool
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Stone Age builders may have been using other materials as well, according to a new study. Archaeologists have discovered the oldest evidence of artificial structures made of wood, dating back almost half a million years – predating the appearance of our own species and suggesting our relatives settled down much earlier than we thought.

The discovery was made at the archaeological site of Kalambo Falls in Zambia, where archaeologists found two logs joined together in an almost cross-like shape. Clear cut marks from stone tools were found on the wood, indicating they had been deliberately cut and crafted into this structure. Exactly what its purpose was remains lost to time, but the scientists speculate that it could be part of a foundation for a platform or shelter.

To determine how old the structures are, the researchers used a technique called luminescence dating. This method allows scientists to calculate when a sample was last exposed to sunlight, indicating how long it has been buried and, as such, a minimum age. When they performed this on minerals in the sand in which the logs were buried, they came up with an astonishing number – around 476,000 years old, placing it in the early Stone Age.

The structure is made up of two logs cut and crafted into a kind of cross-shape
Professor Larry Barham, University of Liverpool

Previous finds have shown that early humans were making tools, weapons and other instruments out of wood even earlier, but this marks the oldest known evidence of construction with the material. In fact, it predates the existence of Homo sapiens as a species, which is thought to have evolved around 300,000 years ago. The researchers don’t speculate on which species might be responsible, but many of our ancestors and relatives were plodding around Africa at that time, including Homo erectus and Homo heidelbergensis.

One of the main reasons we don’t often see wood that old is obvious – it just doesn’t last very long. The archaeological site at Kalambo Falls helps preserve these organic materials for longer thanks to its high water levels.

The discovery shakes up our understanding of human history in other ways too. It was long thought that Stone Age humans were nomadic, roaming around to different regions with the seasons. But building structures suggests they were settling down – and why not? The Kalambo Falls area would have been a stable source of water, while the forests around it provided ample food.

“This find has changed how I think about our early ancestors,” said Professor Larry Barham, corresponding author of the study. “Look at what these people were doing: they made something new, and large, from wood. They used their intelligence, imagination, and skills to create something they’d never seen before, something that had never previously existed. 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. These folks were more like us than we thought.”

The research was published in the journal Nature. The researchers describe the discovery in the video below.

Source: University of Liverpool

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4 comments
TechGazer
Wood can be easier to chop if it's resting on another log. It could also be someone testing the edge of his new axe. It could even be a tree falling on some sharp rocks, and getting swept via a flood onto another log. Two pieces of wood does not prove that it was a man-made structure. I saw a fallen aspen tree that looked at first glance exactly like a tree that someone has chainsawed into firewood (consistent length pieces, straight "cuts"), but it simply fell that way and the soft punky wood snapped into pieces.

There was a Far Side comic about two archaeologists arguing about a cylindrical object they dug up; one insisted it was part of a legbone of one dinosaur, and the other it was part of a different dinosaur, and a third person pointed out that it was just a piece of old stovepipe. Interpretations, especially of fragments of ancient things, can vary greatly from the truth.
Pupp1
Keep in mind that radiometric dating is not nearly as clear-cut as many people expect. Yes, radioactive decay seems to be very predictable. But, there are several other assumptions when actually attempting to date something based on it. For example, the same kinds of dating techniques used to date this wood, if applied to modern igneous rock, with known dates under 1,000 years, you can get dates in the same range as this wood. It is often presumed that these modern samples are somehow contaminated by an unknown source. Yet, much more ancient rocks are presumed to be free from that same potential contamination.

Also, it is generally expected to choose the dating method you expect will be appropriate for the predicted age of the rock. And since C14's short half-life would have long decayed before a half million years, it would be theoretically be useless to attempt a C14 test. Yes, when C14 testing is implemented on things like diamonds, which are presumed to be older than a billion years, they show C14 dates around 40,000 (if one assumes the current rate of C14 formation). But, even if the diamonds were pure C14, there shouldn't be any C14 left. For those who favor the billions of years, the source of C14 remains unknown. The idea that the dates they expect could be wrong is apparently unfathomable to them.
Baker Steve
Awesome. Presumably archaeologists have satisfied themselves that there is no possiblity of newer wood becoming embedded in older sediment.
John
Could be a yoke as in between oxen. There is a horses head beneath, upper rhs.