Indo-European tree
Linguistics, the scientific study of language, can reach more deeply into the human past than the most ancient written records. It compares related languages to reconstruct their immediate progenitors and eventually their ultimate ancestor, or protolanguage. The protolanguage in turn illuminates the lives of its speakers and locates them in time and place.
The science developed from the study of the Indo-European superfamily of languages, by far the largest in number of languages and number of speakers. Nearly half of the world's population speaks an Indo-European language as a first language; six of the 10 languages in which Scientific American appears�English, French, German, Italian, Russian and Spanish�belong to this superfamily.
Over the past 200 years, linguists have reconstructed the vocabulary and syntax of the postulated Indo-European protolanguage with increasing confidence and insight. They have tried to unravel the paths by which the language broke into daughter languages that spread throughout Eurasia, seeking at the origin of those paths the homeland of the protolanguage itself. The early investigators placed the homeland in Europe and posited migratory paths by which the daughter languages evolved into clearly defined Eastern or Western branches. Our work indicates that the protolanguage originated more than 6,000 years ago in eastern Anatolia and that some daughter languages must have differentiated in the course of migrations that took them first to the East and later to the West.