Melissa Wright, a linguist at Birmingham City University, specializes in “the relationship between the phonetic-linguistic details of everyday talk and the interactional structures within which (and through which) that talk is produced”; at her home page, she says of her PD thesis: “I examined the phonetic and interactional organisation of naturally-occurring British and American English conversation. I showed that there are complex and systematic mappings between clicks and interactional structures in talk, a finding which is striking given that clicks have so far been regarded by linguists as functioning only paralinguistically.” Her recent paper “On clicks in English talk-in-interaction” (Journal of the International Phonetic Association 41: 207-229; abstract) has been briefly described in this Scientific American article by Anne Pycha as follows:
Speakers, it turns out, use clicks for a previously overlooked purpose: as a form of verbal punctuation in between thoughts or phrases. Melissa Wright [...] recently analyzed click sounds in six large sets of recorded English conversations. She found that speakers used clicks frequently to signal that they were ending one stretch of conversation and shifting to a new one. For example, a speaker might say, “Yeah, that was a great game,” produce a click, then say, “The reason I’m calling is to invite you to dinner tomorrow.”
This pattern, which occurred for both British and American speakers, suggests that clicks have a meaning similar to saying “anyway” or “so.” That is, clicks provide us with a phonetic resource to organize conversations and communicate our intentions to listeners. This finding had previously eluded linguists, whose research often focuses on words and sentences in isolation. Wright was able to uncover the new pattern because she analyzed clicks in the context of complete conversations, suggesting that this method could be important for making new discoveries about the nature of language.
I don’t know if the “new discoveries about the nature of language” thing is from Wright’s paper or added by Pycha to spice things up; it raised my eyebrows, but not as much as the succeeding paragraph about, yes, the origin of language, for which see this exasperated 2003 LH post. (Thanks, Paul!)