NEW STUDY SUGGESTS THAT LANGUAGE ORIGINATED IN SOUTHERN AFRICA

A researcher analyzing the sounds in languages spoken around the world has detected an ancient signal that points to southern Africa as the place where modern human language originated.

The finding fits well with the evidence from fossil skulls and DNA that modern humans originated in Africa. It also implies, though does not prove, that modern language originated only once, an issue of considerable controversy among linguists.

The detection of such an ancient signal in language is surprising. Because words change so rapidly, many linguists think that languages cannot be traced very far back in time. The oldest language tree so far reconstructed, that of the Indo-European family, which includes English, goes back 9,000 years at most.

Quentin D. Atkinson, a biologist at the University of Auckland in New Zealand, has shattered this time barrier, if his claim is correct, by looking not at words but at phonemes — the consonants, vowels and tones that are the simplest elements of language. Dr. Atkinson, an expert at applying mathematical methods to linguistics, has found a simple but striking pattern in some 500 languages spoken throughout the world: A language area uses fewer phonemes the farther that early humans had to travel from Africa to reach it.

Some of the click-using languages of Africa have more than 100 phonemes, whereas Hawaiian, toward the far end of the human migration route out of Africa, has only 13. English has about 45 phonemes.

This pattern of decreasing diversity with distance, similar to the well-established decrease in genetic diversity with distance from Africa, implies that the origin of modern human language is in the region of southwestern Africa, Dr. Atkinson says in an article published in the journal Science.

Language is at least 50,000 years old, the date that modern humans dispersed from Africa, and some experts say it is at least 100,000 years old. Dr. Atkinson, if his work is correct, is picking up a distant echo from this far back in time.

Linguists tend to dismiss any claims to have found traces of language older than 10,000 years, “but this paper comes closest to convincing me that this type of research is possible,” said Martin Haspelmath, a linguist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

“We’re uneasy about mathematical modeling that we don’t understand juxtaposed to philological modeling that we do understand,” Brian D. Joseph, a linguist at Ohio State University, said about the Indo-European tree. But he thinks that linguists may be more willing to accept Dr. Atkinson’s new article because it does not conflict with any established area of linguistic scholarship.

Dr. Atkinson’s finding fits with other evidence about the origins of language. The Bushmen of the Kalahari Desert belong to one of the earliest branches of the genetic tree based on human mitochondrial DNA. Their languages belong to a family known as Khoisan and include many click sounds, which seem to be a very ancient feature of language. And they live in southern Africa, which Dr. Atkinson’s calculations point to as the origin of language. But whether Khoisan is closest to some ancestral form of language “is not something my method can speak to,” Dr. Atkinson said.

“What’s so remarkable about this work is that it shows language doesn’t change all that fast — it retains a signal of its ancestry over tens of thousands of years,” said Mark Pagel, a biologist at the University of Reading in England who advised Dr. Atkinson. Dr. Pagel sees language as central to human expansion across the globe.

In the wake of modern human expansion, archaic human species like the Neanderthals were wiped out and large species of game, fossil evidence shows, fell into extinction on every continent shortly after the arrival of modern humans.