Proto-languages
A proto-language is the original language from which a group of languages evolved. For related languages, this is their common ancestor. For example, Latin is the proto-language of the Romance language family, which includes French, Italian, Portuguese, Romanian, Catalan, and Spanish.
In The Hesperus Prophecy, while ascending to the top of the Epistolith’s Sanctuary, James and Declan examine the text written on the support columns. This writing is the proto-language for all languages, meaning all human languages developed from this common ancestor. Scholars disagree on how long humans have used language, some estimates are between 1 to 2 million years, others believe it’s much shorter, only the last 70,000 years. Hesperus knows for certain because he was here, teaching us.
Indo-European Languages Family Tree