Rope was just as important a tool during the Paleolithic Era as it is now. But unlike today, back then hunters and gatherers didn’t have machines to twist or braid the fibers into a tough, strong cord. So how, exactly, did they make this vital resource?

A team of researchers from Germany’s University of Tübingen and Belgium’s University of Liège think they’ve found the answer, UPI reports: by using mammoth ivory tools that were specially designed to weave plant fibers together. These findings were recently published in Archäologische Ausgrabungen Baden-Württemberg, a German archaeology journal.

The researchers reached this conclusion after they analyzed a 40,000-year-old piece of mammoth ivory found inside the Hohle Fels Cave in southwestern Germany. (The cave is famous for its cave paintings and artifacts, including the Venus of Hohle Fels, one of the earliest human figurines ever discovered, and a sublime bird bone flute.) Nicholas Conard, founding director of the University of Tübingen’s Institute of Archaeological Sciences, led the expedition that unearthed the well-preserved artifact in August 2015, Science News writes.

The ivory piece is about 8 inches long, and it contains four holes, each less than an inch in diameter. They’re all lined with deep, spiral cuts. In the past, experts have theorized that similar ivory finds were used as musical instruments, shelf straighteners, or artworks. To test her hypothesis that this one was a rope-making tool, archaeologist Veerle Rots of the University of Liège made replicas of the well-preserved device. She then used them to make rope from plant fibers that grow near Hohle Fels. 

"This tool answers the question of how rope was made in the Paleolithic," Rots said in a press release. The question, she says, “has puzzled scientists for decades."

The tool is currently on exhibit at the Urgeschichtliches Museum in Blaubeuren. You can see how it works in the videos below. 

[h/t UPI]

All photos courtesy of the University of Tübingen

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