One of the greatest mysteries of science is the origin of human language. A lack of empirical evidence has forced researchers to rely on fossil records, observations of how animals communicate, contemporary linguistic comparisons and other indirect studies.

As a result, two contrasting schools of thought have arisen. One side says the complexity of language means it must have evolved from the pre-linguistic systems used by our primate ancestors. The other side argues that human language is so unique, it could not have started with non-humans; it must have appeared rather suddenly, perhaps as recently as 100,000 years ago.

So controversial was the subject in the 19th century that the Société Linguistique de Paris (Linguistic Society of Paris) banned papers and debates on it in 1866. That prohibition influenced Western linguists for more than a century, and only recently has the topic been given new life. Today numerous camps have their champions, each offering strong arguments that are difficult to refute.

A Variety of Theories

A majority of scholars on language origin hold that the human faculty must have developed gradually over a long period of time. Among them are the Canadian-born linguist and experimental psychologist Steven Pinker of Harvard University, cognitive scientist Ib Ulbæk HYPERLINK “http://en.wikipedia.org/wiki/Origin_of_language” \l “cite_note-10#cite_note-10” of Denmark’s Roskilde University and American developmental psychologist Michael Tomasello of Germany’s Max Planck Institute for Evolutionary Anthropology. To them, language is instinctual, a biological adaptation that has been shaped by natural selection

Some of those who favor “continuity theories” of human language believe it started with gestures, later accompanied by vocalizations. Others point to early human capacities for song—mothers naturally cooing to their babies or hunters mimicking bird calls and the like—eventually giving rise to more distinct meanings. They can point to the cognitively controlled aspects of primate communication as a potential source.

Representative of the “discontinuity” position is Noam Chomsky, a professor in the Department of Linguistics & Philosophy at MIT who is sometimes referred to as the “father of modern linguistics.” Chomsky has proposed that human language is genetic in nature. It abruptly came into existence as the consequence of a single chance mutation occurring in one individual, and there is both biological and mathematical evidence to support this claim.

A few linguists have attempted to transcend the divide between continuity and discontinuity by advocating a theory of social transformation as the cause of language emergence. They point to chimpanzees and bonobos living in the wild that rarely if ever use the latent symbolic capacities they demonstrate in laboratory experiments. Some social trigger must have awakened the dormant ability in humans.

Areas of Agreement

While disagreeing on origins, where linguists begin to come together is in their understanding of the timing of human language development. In 1998, linguist Johanna Nichols of the University of California, Berkeley used statistical methods to show the time required to reach the spread and diversity in modern languages today. She estimated that the process of diversification had to begin at least 100,000 years ago. That just happens to coincide perfectly with anthropologists’ widely accepted time frame of 150000~50000 BCE for the emergence among humans of “behavioral modernity,” including cultural creativity and symbolic thought.

At the other end of the time scale, experts agree that there are there are no “primitive” languages in existence today. All modern human populations speak languages that have “comparable expressive power.” There may be differences in complexity, but all current languages have transformed to a degree that no truly primitive one has survived intact.

Another area of consensus regards written language. As indicated by archeological finds, humans have created pictures representing their environment for at least 40,000 years, but the coding of pictures into a symbolic language is no older than 5,500 years, when the first Sumerian pictographs were recorded in stone. It would take another 2,000 years or so for such “glyphs” to represent spoken syllables as opposed to objects or actions, and the first true “alphabet” was not developed by the Phoenicians until 1200 BCE.

Interestingly enough, the evolution of written language may give some support to the concept of social transformation being the critical factor in the development of human language in general. Egyptian proto-hieroglyphics and Sumerian pictographs evolved separately but within a few hundred years of each other. Chinese written script evolved on its own, too, but nearly 2,000 years behind those of Mesopotamia/Egypt, which is roughly the same time gap that exists between the start of agriculture in the Fertile Crescent (9000 BCE) and in the Yangtze and Yellow River basins (7000 BCE).

Modern Language Evolution

Today, linguists classify languages into monogenetic units called “families” that reflect their origins and ancestry: Germanic, Italic, Sinitic, Semitic, etc. Clusters of language families are grouped into phylogenetic units or “branches.” Of the world’s current population of seven billion people, roughly two-thirds speak languages belonging to one of the two major branches: Indo-European (i.e., English, Spanish, Hindi, etc.) and Sino-Tibetan (i.e., Chinese, Burmese, Tibetan, etc.). Another 12 percent have either Niger-Congo or Afro-Asiatic languages as their mother tongue.

Oddly enough, the commonalities between languages can be far greater than the differences. During the past decade, considerable research has been conducted on “cognates”—words of common origin that sound similar in various languages and have almost the same meaning, such as “moon” in English and “maan” in Dutch. It has been subsequently discovered that all Indo-European tongues evolved from a common ancestor about 6,000~10,000 years ago.

Of additional interest is the pace of language evolution. Data compiled by the University of Reading in England has shown that it takes about 750 years to replace the less frequently used words in a language. More common words, however, are about ten times more stable. That explains why the number “three” in English is still remarkably close to “tres” in Spanish, “theen” in Hindi, “trei” in Romanian, “tri” in Slavic, and so on.

Affecting language development are such factors as commerce, migration, conquest, isolation, economic progress, cultural shifts and more. In the case of written language, change can be politically instigated, too. That was certainly the case in 1964 when “simplified Chinese” was first put to public use by the Chinese Communist Party under Mao Zedong (毛泽东), just as it was in 1972 when Malaysia introduced a new system of spelling called “Ejaan Baru” for anything written in the local language, Bahasa Melayu.