His rite of spring was known for irregularity, but I am not sure about the details..
<span> In “The Rite of Spring” Stravinsky turned the musical hierarchy up side down The melody is (mostly snippets and shards, turned
this way and that, as a Cubist would an object) and harmony (bi-tonal)
in service to it.</span>
I have not yet used this but maybe it will be a good answering source
Portraits were important in early history because if we had found those paintings and pictures we can determine what there life back then was and what materials they had in the past then what higher materials we have now.
ENJOY