Cool article on music and evolution today in the New York Times. Relevant quote: "Dr. Miller sees music as an excellent indicator of fitness in the Darwinian struggle for survival. Since music draws on so many of the brain's faculties, it vouches for the health of the organ as a whole. And since music in ancient cultures seems often to have been linked with dancing, a good fitness indicator for the rest of the body, anyone who could sing and dance well was advertising the general excellence of their mental and physical genes to a potential mate." Nice :-). I also heard about some of this on NPR a while ago: Origins of Music May Lie in Speech.