clicks are hard to do

i caught a bit of Fresh Air on NPR as i was running an errand this afternoon. they were replaying an interview from about a year ago, featuring Nicholas Wade, a science reporter from the New York Times. the segment is entitled "DNA Analysis Illuminates the History of Man" and one part of it is dedicated to the spread of language in and outside of Africa as early human populations moved around that part of the world and genetically diverged from one another. Mr. Wade is obviously not a linguist, but said nothing really objectionable until this, regarding why there are a small set of languages that exhibit click sounds:

clicks are quite hard to do...it's very hard to do a double click, which several of these languages have. so it looks like once you have clicks you can lose them, but it's very hard to see anyone inventing a click from scratch. so if that's the case clicks have only been lost and not gained, and they must be of great antiquity.

now i remember my introductory phonology class and i remember saying "these sounds are hard to do" during our unit on non-English sounds. but to say objectively that sounds are hard to do is ridiculous. sounds are either possible or impossible (and some are impossible, just because the vocal tract doesn't create the shape that would cause such a sound). non-native sounds can be difficult for people to do. for example, i cannot, no matter how hard i try, produce a trill r, but if i had grown up in Italy, where the trill r is part of the native language, i would be able to produce them perfectly. Wade's assertion that clicks wouldn't be invented because they are hard to do is preposterous. furthermore, they must have been started by somebody, and there doesn't seem to be any compelling reason why these earlier humans would be more likely to "invent" the click than modern humans, who wouldn't do such a silly thing. it's true, native speakers of English aren't going to be going around trying out clicks and inserting them into their speech and saying "hey this is the Cool New Thing in phonemes, so everyone should adopt it." i suppose the bottom line of the story, which was that the peoples who do speak click languages have highly similar genetics, is valid and useful to both anthropologists and linguists. it also has scientific basis for uniting and distinguishing these peoples, but i guarantee that they don't pride themselves on the difficulty of their language.