Scientists are unearthing "verbal gestures"-- changes in pitch, speed that help convey emotion and also movement. Also, a deep voice helps with for male hierarchy stuff, like dominance. If you sound big, you probably ARE big.
Also, vision and sound may work together very closely. Although, after reading this article, I must comment that anybody who can't find rhythm in dancing even with the sound off probably is so tone-deaf they can't keep time.
The subject of sound playing a role in animal communication is a fascinating subject, and I recommend "Animal Talk" by Tim Friend which covers sound, vision, electric signals, touch, smell, etc. It is a wonderful effort to condense the research for the lay public. I had so many questions after reading about acoustic communication.
For instance, the clicker is promoted as a "neutral" sound for dog training but I always doubted this, just from watching how my mom reacted to my playing with a cricket-type clicker once (she nearly strangled me). The information Tim Friend covers about short, sharp and abrupt sounds strongly supports my doubts that the clicker is that "neutral" to the ears.
I'm now reading Musicophilia by Oliver Sacks and I'm finding it really interesting reading; Oliver Sacks is a neurologist and he covers all the facets of music, including hearing music, hallucinating music, so he also covers a lot about deafness (and not just Beethoven). It seems many late-deafened deaf people often hallucinate music as their hearing goes. He also covers how partial hearing loss can affect enjoyment of music. And for the normal-eared folks, an overview of tune cooties or earworms is interesting, although perhaps not quite what some readers were expecting.
Oliver Sacks tends to think this is primarily music-oriented although he mentions poetry can sometimes do the same effect. This research indicates though, that the lyrics are often the focus of why the tune cootie sticks in the mind. I know myself I can wake up with a silly phrase I read somewhere stuck in my head; often poetic or just unusual in its phrasing.
Oliver Sacks talks about how music seems unreleated to the real world.
Ah, Tim Friend would disagree; he writes at length in his "Animal Talk" about how animals in dense forest use sound to communicate, find food, and even orient themselves-- every inch of forest can sound uniquely different because of the different mix of plants, and he points out that orchestral music may mimic the complex chorus of the rainforest. If you want to know the true origins of music's appeal, Tim Friend's book is it.