Singing, the vocal production of musical tones, …with origins long lost in antiquity and predating the development of spoken language. The voice is presumed to be the original musical instrument, and there is no human culture, no matter how remote or isolated, that does not sing. Not only is singing ancient and universal, in primitive cultures it is an important function associated not so much with entertainment or frivolity as with matters vital to the individual, social group, or religion. Primitive man sings to invoke his gods with prayers and incantations, celebrate his rites of passage with chants and songs, and recount his history and heroics with ballads and epics. There are even cultures that regard singing as such an awesome act they have creation myths relating that they were sung into existence.
It is likely the earliest singing was individualistic and improvisatory, a simple imitation of the sounds heard in nature. At what point the singing of meaningful, communicative sounds began cannot be established, but it was doubtless an important step in the creation of language. Many anthropologists believe the development of a lowered larynx (important to articulate speech, as it effectively makes the flexible lower tongue the front wall of the pharynx) was a relatively recent aspect of human evolution.
There are no bones in the human larynx, so archaeological remains offer no direct physical evidence of the vocal apparatus of prehistoric man. We lack studies that correlate vocal characteristics to body size, the basic gender difference aside, but there is general belief large-bodied peoples (Slavs, for example) frequently produce low-voiced singers, while small-bodied peoples (Mediterraneans, for example) produce more high-voiced singers. If there is any validity in this, the voice that belonged to the owner of the prehistoric jaw bone unearthed in 1909, at Heidelberg, Germany, may have been remarkable–it is half-again the size of a modern jaw.
Carrying the idea of relating body size to vocalism into more recent periods, we see modern man has grown too large to fit the armor of medieval knights and, still more recently, we suspect an increasing rarity of the male alto voice type. Tempting though it is to see a relationship between such things, we lack the means to support it factually.
Based on our knowledge of the singing of present-day primitive peoples, a possible scenario of musical development would begin with simple melodic patterns based on several tones. Pitch matching (several persons singing in unison) might emerge next, with singing in parallel motion (the natural result of women or children singing with men), call-and-answer phrases, drone basses and canon as subsequent steps. All this could lead to an evolving sense of tonic and scale structure (primitive music often uses pentatonic scales) and the development of such basic musical devices as melodic sequences and cadential formulae. (Source https://www2.lawrence.edu/fast/KOOPMAJO/antiquity.html)