The question of language origins may be construed in two quite different ways that are, unfortunately, often confused. On the one hand we may speak of the origin of the language capacity, that is, the universal human capacity to learn and use the language of the culture in which one is raised. While it seems likely that our hominid ancestors such as Eve(1), and much earlier Lucy, probably had linguistic abilities intermediate between those of modern humans and chimpanzees, nothing is really known about the linguistic abilities of such human precursors.
The second sense of language origins, which I will focus on in this article, has to do with the origin of the roughly 5,000 languages currently spoken around the world. Where did these languages come from? In a few instances we actually have a historical record of the origin of certain languages. Thus we are able to trace the various Romance languages--Rumanian, Italian, French, Catalan, Spanish, Portuguese--back through the historical record to their common source, the Latin spoken in Rome some two millennia ago. But even without such historical attestation, we could still recognize that these particular languages share a common origin by the simple fact that they all share resemblant words that are not shared by other languages.
For example, the word for hand in the Romance languages generally looks something like MAN-: Rumanian mina, Italian mano, French main, Catalan ma, Spanish mano, Portuguese mao. We do not need to know that all of these forms derive from the Latin word manus (hand), to recognize that they are similar to one another and contrast sharply with the word for hand in other languages, for example, English hand, Russian ruka, or Japanese te. Furthermore, comparing additional words would reveal that the Romance languages share many such similar words that set them off as a group from other languages. Such historically related languages are called a language family, and the modern descendants of a single original word--the various Romance words for hand in our example--are called cognates.
This evolutionary explanation provides a satisfactory answer to the question of the origin of Spanish, French, or Rumanian, but, at the same time, it raises a further question: What is the origin of the Latin language that gave rise to the various Romance idioms? In other words, where did Latin come from? An English jurist serving in India, Sir William Jones, first gave the answer to this question in 1786 when he observed that the similarities among Latin, (Classical) Greek, and Sanskrit were so numerous, and so precise, that "no philologer could examine them all three, without believing them to have sprung from some common source, which, perhaps, no longer exists."
Indo-European and Proto-Indo-European
During the nineteenth century his even more ancient family that Jones had identified--but not named--came to be known as Indo-European. The Romance languages constitute one branch; other branches include Germanic (English, German, Swedish), Slavic (Russian, Polish, Serbo-Croatian), Baltic (Latvian, Lithuanian), Celtic (Irish, Welsh), Albanian, Greek, Iranian (Farsi), and Indic (Hindi, Bengali). Two branches are extinct: Anatolian (Hittite), spoken 4,000 years ago in present-day Turkey, and Tocharian, spoken in western China in the first millennium A.D. That all of these languages (and many others of course) derive from a single earlier language--Proto-Indo-European--is a fact accepted by all historical linguists. Surprisingly, where this language was actually spoken, and when, remain hotly debated topics to the present day, with the Ukraine at 4,000 B.C. or Anatolia at 7,000 B.C. the favored locations.
Virtually all European languages--and many of those in South Asia--belong to the Indo-European--family. In Europe only Basque, Hungarian, Finnish, Estonian, and Saame (= Lapp, a pejorative term to be avoided) do not. We now have a …