Become more common
(that is how species learn to live in an environment over time)
        
             
        
        
        
Answer:
I'm pretty sure it's "favorite".
Explanation:
Adjectives are something you can take out of the sentence and it'd still make sense. Plus, it's also describing his comic. 
 
        
                    
             
        
        
        
Abstract nouns are essentially nouns that can be interpreted differently by different individuals, such as beauty or maturity. Going by this definition, the abstract noun in the given sentence should be "loyalty".