The Evolution of LanguageTwo papers in the journal Nature this week examine the evolution of language. One measured the frequency at which verbs become more regular (use a simple -ed ending for past tense) over time at a rate inversely proportionate to the square root of their usage frequency. The site Science Codex has an article on the paper with interviews with some of the involved researchers.
The other paper looks at why some words use similar word forms across the entire Indo-European language family while others appear as unrelated forms. According to a press release from Nature:
Mark Pagel and colleagues used a statistical modelling technique to analyse four Indo-European languages: English, Spanish, Russian and Greek, and compared this to a database of 200 fundamental vocabulary meanings in 87 languages. They found that across all 200 meanings, commonly used words, such as numbers, evolve much more slowly, suggesting that the frequency with which specific words are used affects their rate of replacement over thousands of years.Again, and with some appeal to common sense, the conclusion is that frequent use cements the form more thoroughly through the act of repetition.