Do you ever find yourself gesturing with your hands as you talk on the phone to someone who can't see you? It seems so natural that we don't think about it. Is that something we learned, or something that just comes with language? Lauren Gawne is a linguist who studies gestures in different cultures. She tells us that people who have never been able to see use gestures when they speak, and will gesture even when speaking to another blind person.
Further, blind people will use the same kinds of gestures that other people with the same language use. but that doesn't always work across different languages. A study of blind people who speak English or Turkish showed that speakers of both languages use the same gestures that sighted people speaking the same language use, but the gestures that matched other English speakers are not the same gestures that (blind and sighted) people speaking Turkish used. Since these gestures were not learned by watching, there must be something about the language that naturally includes gestures. -via Metafilter, where you'll find more links.
(Image credit: Derrick Coetzee)