> How in the world did music come into existence and become ingrained in virtually all of humanity?

One interesting fact to point out is that every culture that ever had a practice of humming while meditating hums at the same pitch. It's approximately a low C sharp, which is the natural resonance frequency of the Earth.

As for how it came into existence, well, you got me. Perhaps it was part of this Earth resonance, perhaps it was listening to birds or other animals and imitating them, perhaps it was the observation of blowing into different lengths of tubes, there's no way to know. The fact is that people liked it, and it stuck around.

In terms of the development of Western music, it began in its infancy as Gregorian chant in the sacred realm and simple dance or folk tunes in the secular area. Back around then pretty much everyone was sworn to the church, so there was a lot of musical exposure there, and the secular music was a way of passing the time.

The coming centuries only saw music grow with increasingly larger steps. It was very much part of the church still, and instrumental music and operas emerged to please the crowds. And it kept going. Nowadays, you can't go anywhere without being bombarded by some form of music.

So I guess my answer for why music is ingrained in humanity, is tradition. We've pretty much always had it, and it's too good to let go. There's also the unexplainable emotional factor: how is it that a song, nothing more than a series of overlaid frequencies and harmonics in different combinations and intensities, is able to make us feel happy, sad, or anything else for that matter? How does it evoke memories?

As for the all of humanity part, well, pretty much every culture has developed music in their own way. (For example, Indian music subdivides the octave into many more notes than our twelve note system, which is why it is often portrayed as "squeally" or out of tune. On the other hand, much of older Asian music used a pentatonic scale; improvise a simple melody only using the black keys on a piano and see how Oriental you think it sounds.) I think it's fair to say that through ritual, tradition, and a basic appeal (name someone who CAN'T find a genre of music they like) we've always just accepted music as granted. It's interesting to consider where humanity might be today without music.

Now, I realize this doesn't really answer too much of the origins of music question, and it's a bit of a half-answer to why it's everywhere. But I just got through my last music course of high school, and by golly I'm going to try to use some of it.

--Mense"Slightly educated. Sort of."kemeser