heh, I never found that particular book BTW

I sowwy
In my opinion it's probably evolved biologically as a social mechanism parallell to linguistics. The human animal is supposedly unique in making culture and art(music in this case), this human animal "lives by being prepared constantly to reinvent itself and the conditions of its existence. For such an animal, music, like the arts in general, would be a crucial device to maintain the necesary(my spelling is crap, stay in school kids) perceptual acuity, world-making flexibility, and range of emotive resource.*" 'Elmo's theory of musical origin'

states that the origin of music can be rooted in the sounds which animals and humans have used in response to events around them. Thus, vocal music is thought of in terms of an extension of the naturally evolved form of voice as a linguistic system, with cognitive intellectual and linguistic function amalgam in it's use. The sounds animals make evoke attitudes, emotions and responses; but we have the added advantage as humans, of the capacity to modulate our speech by linguistic means subjective to understanding. This awareness of linguistic meaning can be expected to influence all uses of voice and thus we develop musical appreiciation.(and by extension, of instrumental music.(Did vocal music develop first?))
But there are a couple of intresting philosophical alternate schools of thought on the subject that suggest that it's a cultural development that has occured unviersally because of a link to the way our minds experience emotion. The most prevelant of these is the Cognitivist theory that says that the experience/interpretation a piece of music engenders is a result of a
conscious process of inference. Implict in this line of thought is the idea that music has expressive properties that the listener's mind recognizes (.
see Peter Kivy,
Music Alone(Peter Kivy is representative of this viewpoint but he's not by any stretch an extremist, he repeatedly states that we are also moved by the way music captures feeling interpreted through a filter of our listening experience(musical and worldly). Thus our culturally learnt listening experience suppresses or facilitates the inherent tendency of music to evoke the corrisponding emotional state(It's probably important to make clear that it's not that we are 'angry' at an 'angry' piece of music

, nor are we angry about it; we merely indentify heard qualities of the music). One theory for example is that the
form of music bears close resemblance to the vocal expressions or bodily movements experienced when emotions or thoughts similar to those interpreted through the music are aroused. If for instance someone is in an agitated or restless emotional state, then their behaviour is liable to be agitated or restlessly; and if they do then they will make agitated or restless movements. Prehaps the type of music the form of which can be described as agitated or restless stimulates the mind in the same way that a agitated or restless emotinal state would(
see Malcolm Buss,
Music and the Emotions). One good problem with this if you are seeking to poke holes in other peoples ideas (and why not? it's very entertaining

), is that when taken to an extreme some people argue that all human minds are biologically disposed to react to a piece of music the same way. Clearly this is not nessecerililly(I can't spell that word, ever.

) so, especially if you take cultural differences into consideration.(I could proove this last point if anyone here is willing to fund my expedition around the world playing music to various cultures.. most likely all the cultures on nice hot sandy beaches, no takers? ..it was worth a shot

)
*Sparshott
Sources for this post include, “Elmo’s old Philosophy notes, vol II”, “my mate Ben”, “Elmo’s diseased mind”