Rope, twine and thread: Invisible technologies of the Stone Age

When an abstract-looking ivory artifact emerged from the Hohle Fels cave in southern Germany in 2015, archaeologists didn't know quite what to make of it. Previously, the same cave had yielded what may be the world's oldest musical flutes, as well as one of humanity's earliest pieces of figurative art, the iconic Venus of Hohle Fels. At first glance, this strange new discovery—a 20-centimeter (8-inch) rod perforated with four small holes—seemed comparatively unspectacular.