Languages, like genes, can tell evolutionary tales

Bruce Bower in Science News:

ScreenHunter_03 Nov. 23 10.44Talk is cheap, but scientific value lurks in all that gab. Words cascading out of countless flapping gums contain secrets about the evolution of language that a new breed of researchers plan to expose with statistical tools borrowed from genetics.

For more than a century, traditional linguists have spent much of their time doing fieldwork — listening to native speakers to pick up on words with similar sounds, such as mother in English and madre in Spanish, and comparing how various tongues arrange subjects, verbs, objects and other grammatical elements into sentences. Such information has allowed investigators to group related languages into families and reconstruct ancestral forms of talk. But linguists generally agree that their methods can revive languages from no more than 10,000 years ago. Borrowing of words and grammar by speakers of neighboring languages, the researchers say, erases evolutionary signals from before that time.

Now a small contingent of researchers, many of them evolutionary biologists who typically have nothing to do with linguistics, are looking at language from in front of their computers, using mathematical techniques imported from the study of DNA to wring scenarios of language evolution out of huge amounts of comparative speech data.

These data analyzers assume that words and other language units change systematically as they are passed from one generation to the next, much the way genes do. Charles Darwin similarly argued in 1871 that languages, like biological species, have evolved into a series of related forms.

And in the same way that geneticists use computerized statistical approaches to put together humankind’s family tree from the DNA of living people and a few long-dead individuals, these newcomers can generate family trees, called phylogenies, for languages.

More here.