BERLIN: Languages do not share a single history but different components evolve along distinct paths, say scientists who have found that grammatical structures change more quickly than vocabulary.
Scientists, including those from the Max Planck Institute for the Science of Human History in Germany, analysed 81 Austronesian languages based on a detailed database of grammatical structures and lexicon.
By analysing these languages, all from a single family and geographic region, using sophisticated modelling the researchers were able to determine how quickly different aspects of the languages had changed.
The study, published in the Proceedings of the National Academy of Sciences, noted that strikingly different processes seemed to be shaping the lexicon and the grammar.
The lexicon changed more when new languages were created, while the grammatical structures were more affected by contact with other languages, researchers said.
"We found striking differences in the overall pattern of rates of change between the basic vocabulary and the grammatical features of a language," said Simon Greenhill from Max Planck Institute for the Science of Human History.
"The grammatical structures changed much more quickly and seemed to be more likely to be affected by neighbouring languages, while the lexicon changed more as new languages were formed," Greenhill said.
Researchers noted that there were specific elements of both vocabulary and grammar that change at a slow rate, as well as elements that change more quickly.
One interesting finding was that the slowly evolving grammatical structures tended to be those that speakers are less aware of, researchers said.
This was because when two languages come together, or when one language splits into two, speakers of the languages emphasise or adopt certain elements in order to identify or distinguish themselves from others, they said.
"This is a bit of an unexpected finding, since many have thought that grammar might give us deeper insight into the linguistic past than vocabulary, but there is still some reason for caution," said Stephen Levinson from Max Planck Institute for the Science of Human History.
"But what is clear is that grammar and vocabulary changes are not closely coupled, even within branches of a family, so looking at them both significantly advances our ability to reconstruct linguistic history," Levinson added.