We know cave drawings told stories and were a means of communications. But what about macrame? A researcher at St. Andrews University in Scotland says that’s exactly how Inca’s transmitted letters.

In a paper published Monday for the April 9 edition of the journal Current Anthropology, anthropologist Sabine Hyland of the St. Andrews Department of Social Anthropology examined two khipus preserved by a village in Peru that villagers said were sacred texts about warfare.

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The various ways of twisting and knotting animal hairs an cotton fibers and colors contained 95 symbols that amounted to writing. The khipus even contained names at the bottom, formed by distinct fibers, colors produced by dies and ply direction.

Spanish witnesses long claimed khipus contained historical narratives, biographies and epistles, but scholars dismissed them as memory aids, providing simple mnemonic tools rather than providing a writing system to preserve information.

“I examined two khipus safeguarded by indigenous authorities in the remote Andean village of San Juan de Collata,” Hyland wrote. “Village leaders state that these khipus are narrative epistles about warfare created by local chiefs. The existence of epistles, comprehensible to recipients, implies a shared communication system.”

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People in seven central Andean villages still hold khipus, mostly as a historic legacy rather than a means of communication. Some are used for accounting purposes.

“In Collata, the khipus were stored in a sacred wooden box containing over 100 manuscripts. … The khipus show little evidence of felting, indicating that they have not been handled frequently. While highly valued, the manuscripts are not generally consulted in village affairs, although one senior man reads through them in his spare time. … Collata is the only village in the Andes where colonial manuscripts and khipus are known to be preserved together in the same archive,” Hyland said.

The existence of the box was a well-guarded secret among village elders until recently. The preserved khipus were created in the 18th century around the time of the rebellions against the Spanish conquerors.

“Evidence suggests that Andeans composed khipu epistles during the rebellions to ensure secrecy and affirm cultural legitimacy. … Spanish chroniclers … stated that Inca runners, known as chasquis, carried khipus as letters during the Inca period,” Hyland wrote.

About 600 khipus similar to those found in Collata can be found in museums and private collections around the world. Several have been classified as fakes because they deviate from what was considered the norm. Hyland said they probably should be re-examined in light of her research.

Harvard University archaeologist Gary Urton told ScienceNews, however, Hyland’s work will do little to decipher the khipus, even though she was able to make out the name “Alluka,” a family name in Collata, at the end of three cords.

The khipu database project at Harvard describes the artifacts as “record-keeping devices” used by the Inca empire, which stretched from Ecuador to Chile, from about 1400 through the Spanish conquest of Peru in 1532.

“The word khipu comes from the Quechua word for knot and denotes both singular and plural. Khipu are textile artifacts composed of cords of cotton or occasionally camelid fiber,” the database says. “The cords are arranged such that there is one main cord, called a primary cord, from which many pendant cords hang. There may be additional cords attached to a pendant cord; these are termed subsidiaries. Some khipu have up to 10 or 12 levels of subsidiaries” and when rolled for easy transport, resemble a mop.

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