Writhing in Coils

It turns out that the fiber arts, one of the earliest and most important foundations of civilization, follows an ironclad geometric rule called "zero-twist configuration". Everything from DNA to silk thread to Golden Gate bridge cables thick as tree trunks all obey the same rule: A twisted, multistrand rope under tension stops twisting when the result is 68% of its original length, and at that point, it won't unwind if you bind off the ends. This peculiar rule is based on math, not what the rope is made of! Curiously, the geometry is recursive: Ropes can be used like fiber strands to make bigger ropes.

What that means is, the spinster's craft and children's tops† are inevitable in the universe, not just in human history. And that means, yarns and weaving probably date to the late Paleolithic, and will be found anywhere in the universe where life is intelligent. Rope-making may even be a definition of intelligence. Wool-gathering rather obviously can predate shearing domesticated livestock‡, so it probably did. Should some of those stone "hide scrapers" be reexamined for evidence of fiber shearing, such as microscopic striations against the razor's edge made by silica grit in the wool or hair?

†Old-fashioned tops, the kind you wind a string around and then throw, are obviously a variation on the drop spindle. As Bohr and Olsen point out in the article, tops are also an early tool used by ropemakers.

‡Imagine a group of wool-gatherers, probably women, following a herd of sheep through the scrublands, picking clumps of fiber off the thornbushes. Same as cotton, same as milkweed pods. Their worlds are full of stuff.