Not the same as emulating vowels and consonants, but my dad used to whistle by with two fingers on his lips and making the loudest whistle. Either to get the dog's attention or my attention as a child.
It was a rural area and he used it to communicate (come back home, usually) and as a child I could tell by the sound if it was a normal 'come home' or one where I was in trouble 'come home right now!'
I now have a child of my own and kind of wish I could whistle like that, though the utility would be much less living in a city with endless forms of electronic communication.
Apparently that sort of whistling is also used for communication, at least if Wikipedia is to be believed [0] (or if I could track down the source, which I don’t feel like doing just right now):
> Sochiapam Chinantec has three different words for whistle-speech: sie³ for whistling with the tongue against the alveolar ridge, jui̵³² for bilabial whistling, and juo² for finger-in-the-mouth whistling. These are used for communication over varying distances.
It was a rural area and he used it to communicate (come back home, usually) and as a child I could tell by the sound if it was a normal 'come home' or one where I was in trouble 'come home right now!'
I now have a child of my own and kind of wish I could whistle like that, though the utility would be much less living in a city with endless forms of electronic communication.