Why do We Find Things Beautiful?

I understand why we find other people beautiful (or not), it's a rudimentary method of picking a suitable mate, or at least cutting the numbers down significantly. This obviously has survival implications reproduction implications. I also understand why we find babies (and other animals with similar traits) cute, it increases the likelihood we will nurture and protect the child while it is vulnerable, to allow us to form bonds which increase the chances of it making it to breeding age. I'm realise I'm boiling things down, possibly a little too far, but there you go.

So, I can see a reason for that, but does it extend to other things? I often look up at the sky and see a sight that makes me think "wow, that's beautiful/stunning/amazing.' Is that a useful function too? Why do we find sunrises and sunsets beautiful? Maybe we just like fair skies and that it indicates good weather, easier living (when you're outside all the time rain is not a nice thing) or maybe just a sign that the sun will hit us today and help us produce vitamin D. Likewise when you look at a beautiful landscape, maybe the trigger is identifying fertile land or a plentiful food source, maybe not. Explaining why we find certain combinations of colours, art, shapes and objects beautiful is perhaps harder to explain, maybe they are all do filter back to some primeval recognition system that helped us survive.

The concept itself has a great deal of power, stirring our emotions, causing reflection and contemplation. I'm not certain that it's something essential to our development and survival and continuation of the species, which makes you wonder what it is and why why experience it.

Reading through the Wikipedia article on Beauty raised some interesting points about the Golden Ratio, which draws a link between mathematics and beauty. The Golden Ratio (1.6180339887) is the relationship between two values, the idea being that many elements that make up a beautiful body match the Golden Ratio (spacing of eyes and mouth, etc). Also, the idea that beauty is linked to good and ugliness to evil (and also innocent and deadly), and interesting idea when you think about it.

Beauty seems to fit into the larger scope of Aesthetics, but I'm not sure I'm any closer to understanding why we feel it, especially towards nature or inanimate objects or its purpose.