Humans feel motivated to create and consume many artistic forms. Why don't other animals produce or consume such things as dance, music, visual art, verbal arts of story and lyric and declamation?
Recognizing patterns and relationships, then applying ones known by experience to new material is something that characterizes human minds and hearts. In abstract terms this search for meaning is an extension from the core motivation in spoken (and thus also written) language. For some reason a given musical phrase, movement sequence, or choice of words stands out in a person's mind. It "means" something or resonates with a feeling or concept in one's own mind, as yet perhaps not articulated into a definite form. The artist answers a specific itch by producing sequences of pattern and meaning. The audience may dwell on a novel piece of work to grasp it, or in dim recognition of knowing it from another place or medium. Alternatively the audience may be actively seeking something to touch the itch they feel, and therefore browse rapidly through the works until they find something partly or fully connected to the meaning they are seeking. In the case of visual arts, the elements of composition, light, texture, narrative (intertexuality) or context could spark the feeling of recognition and personal meaning attached to the work. In other words the meaning can be perceived indirectly, incidentally and thus unintentionally.