Do aliens appreciate beauty? To answer this question we need to understand the biological definition of beauty. We need to understand what beauty means at our core.
Flowers are an example of nature that people, regardless of culture, appreciate for visual beauty. Why are flowers beautiful? Our brains are pattern recognition machines. And, our eyes do not smoothly scan the visual environment. Instead, our gaze constantly jumps from point to point through short rapid eye-movements called saccades. This “jumping” is not random; we are subconsciously trying to recreate the environment in our mind, predicting what we will see next before the following saccade. The geometrical symmetry of a flower allows our brains to understand its structure without looking at the whole of it. Therefore, when we saccade to the next section of the flower, our prediction matches the reality and we experience a small dopamine reward-response. This chemical response verifies our understanding of the visual environment and elevates our emotional state (i.e. we feel good). Flowers are beautiful because their geometric predictability allows us to quickly match the reality to our prediction of what it should be. And, the extent to which it matches our prediction is the same extent to which the flower is beautiful.
Beauty is the extent to which something matches our prediction of what it should be.
Beautiful music is music that allows us to predict the next sequence of sounds. It is for this reason that genres of music exist, featuring groups of music with similar patterns of sounds and allowing our pattern-recognizing brains to specialize. And, as our mental recreation of something translates from prediction to certainty, the reward for that beauty diminishes, much like repetitively listening to the same song. When the next sequence of sounds is so familiar that it is ‘guaranteed’, the song loses its beauty. Beautiful dancing is motion of the body in a way that allows us to predict the next sequence of movements; and, in the same manner as music, there are styles of dance that group similar patterns of movement. Beautiful people are people with traits which we think they should have. Natural beauty, as parks and gardens in our cities, is beautiful because that is what we think the environment should look like. This insight into beauty is really an insight into ourselves.
If we can appreciate beauty for what it is - a verification of our prediction - we can realize the expectation which we are also imposing on our surroundings. We want everything to be beautiful. But, if we don’t understand what beauty is, we don’t understand the implications and consequences of our desire for beauty. With this understanding, we can affect our collective perspective, modify our expectations, and redefine beauty.
Back to our original question: do aliens appreciate beauty? I say yes. As long as our aliens make predictions about their environment, they will inevitably experience beauty; though, they would likely disagree with us on the specifics of what is actually beautiful. Interestingly, they may share the notion of beauty in geometrical and mathematical shapes, such as fractals (and therefore flowers). If these aliens have figured out ways to make deeper and more accurate predictions about their environment (such as by augmenting themselves with more advanced sensory tools) they may experience a type and level of beauty beyond our ability to fathom it. Nevertheless, if you’re going to meet some aliens, it certainly wouldn't hurt to bring some flowers.