In the early 19th Century a small group of Liberians invented a way to write the Vai language down. Instead of copying Roman or Arabic letters, as occurred with most languages first written down in recent times, they invented their own script. This created a rare example where linguists can trace the entire history of a written script. The evolution might settle a debate between theories about how Egyptian hieroglyphics turned into the letters we use today.

The ancestry of our modern letters can be traced back to the walls of ancient Egypt. Most famously, our letter A is thought to be descended from the ox's head drawn by Egyptians via a Phoenician symbol and the Greek alpha. However, there are at least two theories on how this happens. “There’s a famous hypothesis that letters evolve from pictures to abstract signs. But there are also plenty of abstract letter-shapes in early writing,” said Dr Piers Kelly of the University of New England (Australia) in a statement.

Kelly thought it would be useful to compare the evolution of a script whose entire history is documented. In Current Anthropology, Kelly and co-authors trace the development of the script for the Vai language from the 1830s to today.

The Vai language is spoken by around 100,000 people in Liberia, along with a smaller number in neighboring Sierra Leone, and emigrant communities around the world. Until at least 1800 it appears to have been entirely oral, with no written script.

As former American slaves established presence in what became Liberia, Vai speakers became more exposed to the usefulness of writing. However, where the speakers of most other African tongues took the letters of European or Semitic scripts to record their speech, the Vai created their own. Some attribute the invention to a single genius Momolu Duwalu Bukele, others to a small group, but either way the letters spread among Vai speakers and remain widely used today.

The Vai symbols in modern use are not the same as those from our oldest records in 1834 (although some think the language is decades older).

“Because of its isolation, and the way it has continued to develop up until the present day, we thought it might tell us something important about how writing evolves over short spaces of time,” Kelly said. “We predicted...signs will start off as relatively complex and then become simpler across new generations of writers and readers.”

This is indeed what Kelly and co-authors found. The early Vai letters were inspired, supposedly in dreams, by traditional emblems or meant to represent people such as a pregnant woman and a chained slave. As generations learned to draw them, they became steadily simpler, in an accelerated version of what we see with ancient languages.

“Visual complexity is helpful if you’re creating a new writing system. You generate more clues and greater contrasts between signs, which helps illiterate learners,” Kelly said.  “This complexity later gets in the way of efficient reading and reproduction, so it fades away.”

Nigerian philosopher Henry Ibekwe responded to the study saying: “African indigenous scripts remain a vast, untapped repository of semiotic and symbolic information. Many questions remain to be asked.”

Kelly is now studying the way Indigenous Australian message sticks challenge the notion that the widespread continent had no written language prior to colonization.