The pleasure of utility
What is happening when my brain converts the sound vibrations of a Mozart sonata or Maria Callas aria into electrical signals and experiences them? Why does it generate a nice feeling, pleasure? Also, the sensation of joy does not need anyone else to be present, not even the performer. Other than enjoyment, it does not convey any information. It is unlikely that such a complex characteristic would be an accident or vestigial. So why have we evolved to create and experience certain combinations and sequences of sound in an enjoyable way? How does it support life?
From what we observe about the creation, reception and effects of music, it could serve multiple purposes for life.
Art could have evolved in one of several ways, based on its utility for life. One role it could play is to make the registering, analysis, retention and reuse of event sequences that we experience. For example, it rains heavily, and there are mudflows, the hut collapses. Or the cock crows and it is dawn and time to wake up and get going. Drawings and paintings help humans record events and causes and effects. Musical notes in specific sequences create a melody the mind can focus on and follow. Like it can track the flight of the deer and the chase of the lion. In this role, art is a teaching aid for the brain.
The other function it could have is to increase the capacity of the more advanced parts of the brain by exercising them (e.g. the cortex), although they may have evolved a lot before art came into the picture.
Another possibility is that it could help calm the more reactive parts of the brain (which meditation and mindfulness do too).
Art could also, in a secondary role, strengthen the bonding within social groups. The Arts represent the more complex emotions of humans and sharing the experience of music, dance and art could strengthen the bonds within human groups. To the extent that some other species also exhibit the capacity for music and dance, it applies to them too.
Our perception of Art is intimately tied to our senses. Therefore, its existence, form and value are entirely relative to our species. For any other species on our planet, it may be similar but will not be the same. For an alien species with very different sense organs and evolutionary needs, art may not exist or will be very different if it does.
Sunsets over the ocean look good to us. Is it because it is a sign that everything is fine with the world? The life-giving sun is there, just right for us. There’s water, even if it is salty. Music sounds good to us. Is it because it resembles the sounds of natural things that are wholesome for us, such as flowing water, singing birds, flowing air? Is the ability to create and enjoy art only possible when we have leisure time? And because leisure is a sign of satiation, comfort, shelter and safety, does art enhance it by generating positive feelings and make us strive for such conditions?
Then what about sad songs? How are they good for us? How about paintings of war and death? How are they good for us? One answer could be that they remind us of what we should not be, what we should not do. So, art could also be serving the function of reflection and teaching. And it may do it for many of us together. It could be a way for us to agree on what is right for us and what is not.
To sum up, either art makes us more fit for survival directly or pushes us to such behaviour that the enjoyment of art becomes possible in our lives. Either way, it is utilitarian. As an enabler or as a source of pleasurable sensations that accompany healthy activities.