The homelands of the Indo-European languages stretch from Dublin to Delhi. But Hadza, a tongue that is one of a kind, is spoken by just 1,000 people near Lake Eyasi in Tanzania. Why do the world's languages have so uneven a distribution pattern?
The invention of agriculture has long been invoked to explain the spread of the Indo-European languages. Now, Dr. Jared Diamond of the University of California at Los Angeles and Dr. Peter Bellwood of the Australian National University in Canberra have applied the concept to 15 major language families. Their article appeared in the April 25 issue of Science.
The premise is that when humans lived as hunters and gatherers, their populations were small, because wild game and berries can support only so many people. But after an agriculture system was devised, populations expanded, displacing the hunter-gatherers around them and taking their language with them.
On this theory, whatever language happened to be spoken in a region where a crop plant was domesticated expanded along with the farmers who spoke it.
Even if the farmers interbred with the hunter-gatherers whose land they took over, genes can mix, but languages cannot. So the hunter-gatherers would in many cases have adopted the farmers' language. That is why languages "record these processes of demographic expansion more clearly than the genes," Dr. Bellwood said.
Just as China was a powerhouse of new language families in the East, the Fertile Crescent, the arc running through Lebanon and through Iraq, was the source of at least three major language families in the West, the authors say.
One was Dravidian, a language family now centered on southern India. A second was the Indo-European family, which includes English, French and German in its Western branch and Iranian and Hindi in its Eastern branches. A third may have been Afro-Asiatic, a family that includes ancient Egyptian and Semitic languages like Arabic and Hebrew.…
From the New York Times: World's Farmers Sowed Languages as Well as Seeds